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techtalk:ih:oil01 [2022/07/30 05:39] – [Engine Pressures] hippysmack | techtalk:ih:oil01 [2024/06/22 15:15] (current) – [Sub Documents] hippysmack | ||
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====== IH: Oiling & Lubrication ====== | ====== IH: Oiling & Lubrication ====== | ||
====== Engine Oil System ====== | ====== Engine Oil System ====== | ||
- | More pathway details at [[techtalk: | + | The Sportster Oiling Cycle is defined in the FSMs. \\ |
+ | However, that description is vague in some of the intricate transitions of the oil path in the engine. \\ | ||
+ | This page is an attempt to clarify some of the gray areas from the FSM's descriptions with further description and pictures. ((Hippysmack of the XLFORUM)) \\ | ||
- | And in the REF section of the Sportsterpedia, see these: \\ | + | Links to other Oiling pages in the Sportsterpedia: |
* [[techtalk: | * [[techtalk: | ||
* [[techtalk: | * [[techtalk: | ||
* [[techtalk: | * [[techtalk: | ||
+ | * [[techtalk: | ||
+ | * [[techtalk: | ||
+ | Oil Path Drawings: Click on a drawing below to enlarge. ((drawings by Hippysmack)) \\ | ||
- | ====== Engine Oiling ====== | + | {{: |
- | === General Statement === | + | |
- | The Sportster Oiling Cycle is defined in the FSMs. \\ | + | {{: |
- | However, that description is vague in some of the intricate transitions of the oil path in the engine. \\ | + | |
- | This page is an attempt to clarify some of the gray areas from the FSM's descriptions with further description and pictures. ((Hippysmack of the XLFORUM )) \\ | + | |
- | ====== Engine | + | ====== Engine |
- | Different areas have different types of pressure applied and from different sources. ((bustert of the XLFORUM http:// | + | Oil is gravity fed from the oil tank to the oil pump. ((1959-1964 HD Sportster FSM pg 3A-15)) A check valve in the oil pump prevents the oil from draining into the engine by gravity. Then, the oil pump supplies pressurized oil into a hole in the cam cover. That pressurized oil is forced up the lines (between the cylinders) to the rocker box by the oil pump. That is the vertical end of responsibility (pressure wise) for the oil pump. In the rocker boxes, oil gathers and splashes over rocker arm bearings and rods, valve stems, valve springs and pushrod sockets. Before the oil reaches the rocker lines, it splits off to a hole through the pinion shaft (to get to the lower rod bearings). This is the horizontal end of responsibility |
- | **The engine has a force-fed (pressure type) oiling system incorporating oil feed and return pumps in one pump body with a check valve on the feed side.** ((86-90 HD Sportster FSM pg 3-4)) | + | Oil drains from the heads through passages in each cylinder. Then it flows into two holes in the base of each cylinder while lubricating the cylinder walls, pistons, rings and main bearings.((1959-1964 HD Sportster FSM pg 3A-15)) Oil flows from the rocker boxes into the gearcase |
- | * The feed side of the pump forces oil to the engine to lubricate; | + | |
- | * Lower connecting rod bearings | + | |
- | * Rocker arm bushings | + | |
- | * Valve stems | + | |
- | * Valve springs | + | |
- | * Pushrods and tappets | + | |
- | * The scavenge side of the pump returns oil from the bottom of the gearcase | + | |
- | * **It's not unusual to get air out the oil return line (to the tank).** ((aswracing of the xlforum http:// | + | |
- | It's a dry-sump system with an oil pump that's designed to keep the engine sump as dry as it can. \\ | + | |
- | When there' | + | |
- | See also, [[techtalk: | + | |
- | ===== Oil Pump and Pressure ===== | + | Oil accumulated in the crankcase base is scavenged by the flywheels to the breather |
- | **The oil pump doesn' | + | This splash oil blown from the crankcase to the gearcase lubricates the generator drive gear, cam gears and cam bearings. Crankcase exhaust air escapes from the timing gearcase through the outside breather tube.((1959-1964 HD Sportster FSM pg 3A-15)) Any oil still carried by exhaust air is separated form the air by an oil slinger on the generator drive gear.((1959-1964 HD Sportster FSM pg 3A-15)) |
- | That's a bit tongue in cheek since there is a suction side and a pressure | + | Gearcase oil flows through the fine mesh oil strainer preventing foreign particles from entering the scavenge section of the oil pump.((1959-1969 HD Sportster FSM pg 3A-15)) Engine |
- | However, | + | |
- | So in essence, the oil delivery system does make pressure and it can be measured with a gauge. \\ | + | |
- | The oil pump is non-regulated and delivers its entire volume of oil under pressure | + | |
- | Measurable | + | |
- | (i.e. lines, routing, holes and galley sizes) | + | |
- | **Oil is gravity fed from the oil tank to the oil pump.** \\ | + | ====== Engine Oil Cycle (1977 to 1985) ====== |
- | In essence, | + | Oil is gravity fed to the gerotor type oil pump. Oil enters |
- | **However, there is also a vacuum on both the feed and return inlets that does most of the work bringing | + | |
- | It's an added part of the system once the pump starts turning | + | |
- | As the volume between | + | |
- | Likewise, as the RPM lowers, the suction decreases. \\ | + | |
- | The opening action between | + | Oil continues around a groove machined in the outside diameter of the large end of the rocker arm shaft and through the rocker arm arm cover to the exhaust rocker arm shaft lubricating the rocker arm bushings, valves and pushrods in the same manner |
- | The closing action between | + | |
- | ===== Expected Engine | + | Oil collected in the sump area returns to the scavenger section of the oil pump through a passage located in the rear section of the pump. Oil flow to the pump is accomplished by the scavenger effect of the oil pump and the pressure created from the downward stroke of the pistons. ((1970-1978 HD Sportster |
- | See also [[techtalk: | + | |
- | On ironheads, 80% of oil pressure | + | All engine breathing is accomplished through the gearcase into the breather system. Any oil still carried by the exhaust air is centrifugally separated from the air by an oil slinger on the end of the generator drive gear shaft. ((1970-1978 HD Sportster FSM pg 3-7)) Crankcase exhaust air is routed through a one way check valve to the air cleaner. ((1970-1978 HD Sportster FSM pg 3-7)) \\ |
- | The oil pump is non-regulatory and delivers its entire volume of oil under pressure to the oil filter mount. \\ | + | ====== Oil Feed System ====== |
- | When an engine is cold, the engine oil will be more viscous (ie., thicker). \\ | + | ===== Sub Documents ===== |
- | During start-up of a cold engine, oil pressure will be higher than normal and oil circulation will be somewhat restricted within the oiling system. \\ | + | * [[techtalk: |
- | As the engine wams to normal operating temperature, | + | |
- | When an engine | + | The engine |
- | The volume of oil circulated through the oiling system | + | |
- | As engine speed is reduced, | + | |
- | **Ironhead engine oil pressure was measured (by the MoCo) with a pressure gauge at the oil pump**. \\ | + | ===== Role of the Oil Tank ===== |
- | See expected oil pump pressures below (per FSM's): \\ | + | [[techtalk: |
+ | [[techtalk:ref: | ||
- | **Gauge mounted at oil pump**: \\ | + | **The oil tank is both an oil reservoir and air/oil separator**. Return oil comes into the tank carrying both air and oil. \\ |
+ | The oil drops to the bottom while air rises up and out the vent back to the cam chest. | ||
- | As checked with hot oil and a gauge at the oil pressure switch location at the oil pump. \\ | + | **From 1957-1978, the oil tank is also a housing for the oil filter on XL / XLH models**. XLCH models didn't have a factory installed |
- | The oil pressure switch has to be removed for the gauge to be installed. \\ | + | |
- | **1957-1969**: ((1959-1969 HD FSM pgs 3A-11, 3A-15)) \\ | + | **Oil is gravity fed from the oil tank to the oil pump.** What that means is since the oil tank is higher than the pump, gravity pushes oil down to the pump inlet but not into a running motor. It's basically a byproduct of hanging the tank above the pump. Gravity does assist pump suction however. A pressure of less than 1/4 PSI was calculated in the link below as an example on a 1998 model Sportster setup. That 1/4 PSI is just for example only as elevation and oil density will slightly change that number. The point of stating that is there is very little |
- | Minimum: 3-7 psi (idle, with spark retarded) \\ | + | [[techtalk:ref: |
- | Normal riding conditions: 10-14 psi (6 psi at 20 mph) \\ | + | |
- | **1970-1978**: ((HD 70-78 FSM pgs 3-1, 3-5)) \\ | + | **Pressure from gravity constantly pushes oil to the pump's inlet which helps the pump pick up oil through suction from there**. \\ |
- | Minimum: 3-7 psi (idle) \\ | + | The higher the oil tank sits, the higher the oil level sits which increases the NPSHA which is the (Net Positive Suction Head Available) to the pump. \\ |
- | Maximum: 15 psi (60 mph in high gear) \\ | + | [[techtalk:ref: |
- | Normal riding conditions: 4-15 psi | + | The pump requires a positive push of oil to the inlet cavity to function as designed. \\ |
- | **1979-1985**: ((1979-1985 HD FSM pgs 3-1, 3-10)) | + | **Pressure from gravity is also the reason oil from the tank can leak down into the motor when the motor is shut down**. \\ |
- | Minimum: 4-7 psi (idle) \\ | + | [[techtalk:ref:oil10# |
- | Maximum: 10-20 psi (3500 rpm) \\ | + | |
- | Normal riding conditions: 4-15 psi \\ | + | |
- | **Note**: On a cold startup, expect pressure to reach ~60 psi ((IronMick | + | **It's not unusual to get air out the oil return line (to the tank).** ((aswracing |
- | ===== Crankcase Pressure ===== | + | **The oil tank vents separated air back to the gearcase**. The vent line from the tank mostly vents oil tank air back to the gearcase mixed with an oil mist. If the vent line is kinked or blocked, pressure will back up in the tank and pop the cap and splash oil everywhere. 1957-1966 XLH and 1958-1969 XLCH engines vent the oil tank to the gearcase by a hose attached from the oil tank to a fitting on the top of the engine behind the rear cylinder. There is a passage in the engine case that routes from there into the gearcase. 1967-up XLH and 1970-up XLCH engines vent the oil tank to the gearcase by a hose from the oil tank a 90° fitting on the rear of the gearcase cover. \\ |
- | See also [[techtalk: | + | | Oil tank vent fitting on 1973 XLH ((photo by Levi Luther |
+ | |{{: | ||
- | Crankcase air pressure is mainly generated by the up and down movement | + | ===== Role of the Oil Pump - Pressure ===== |
- | The downstroke of the piston causes the volume underneath the pistons | + | [[techtalk: |
- | This pressure is multi use; \\ | + | |
- | * It helps to push sump oil up and out the scavenge passage to the return side of the oil pump. | + | |
- | * It also initiates the splash and mist process as the compressed air above the oil is ready to spring up when the piston rises. | + | |
- | Then the upstroke of the piston creates an upward vacuum bringing some of the oil from the sump with it. \\ | + | The feed side of the oil pump forces oil to the engine |
- | With little | + | Different areas of the motor have different types of pressure applied and from different sources. |
- | Crankcase pressure is essentially cycling between atmospheric | + | The same applies to the oil pump. \\ |
- | (remember, due to the common crankpin 45 degree design, a Harley | + | |
- | This creates splash | + | **Oil pump feed gear / gerotor vacuum sucks oil from the inlet cavity or attached hose respectively into the inlet cavity of the pump**. There is a vacuum created on the inlet cavity of the pump generated by the opening of the gears / gerotors |
- | This also creates an air / oil mix when tiny particles intertwine with the oil in suspension. \\ | + | Too low suction and the gear / gerotor cavities will not completely fill with oil especially on higher RPM and system oil volume will suffer. Too much vacuum and oil vapor may be pulled out of the oil stream and cavitate / damage |
- | The two don't actually mix as does sugar and water. \\ | + | |
- | So separating them back apart is fairly easy if you add an obstacle for that ' | + | |
- | Collision | + | |
- | On all models, the oil tank also doubles as an air / oil separator. \\ | + | |
- | On 57-E84 models, | + | |
- | On L84-85 models, the final separation obstacle is the breather valve in the cam cover. | + | |
- | The piston motions create a pulsating blast of air pressure (push pull condition as each piston rises and falls). \\ | + | **The oil pump pressurizes |
- | Static | + | |
- | (although it takes static | + | |
- | Likewise, crankcase (CC) pressure | + | **The engine is force-fed oil by system |
- | Oil in the crankcase adds resistance to the air pressure | + | |
- | Gravity oil drains from rocker boxes; \\ | + | ===== Engine Oil Pressure, Volume |
- | Returns oil to the crankcase via the drain ports in the heads / cylinders | + | ==== Sub Documents ==== |
+ | * [[techtalk: | ||
- | ==== Some CC Pressure | + | [[techtalk: |
+ | That page consists of where to test, expected oil pressure for the respective year models and a link to the page for installing a pressure gauge. \\ | ||
- | Some of the oil is picked up by the piston upstroke and mixed with the air pressure | + | On Ironheads, 80% of oil pressure is sent to the bottom end and 20% is sent to the top end according to MMI. ((2000 MMI Documents)) Ironhead engine |
- | The mist and splash | + | The FSMs say the oil pump is non-regulatory |
- | And they are also carried into the gearcase compartment to help lubricate the cams and pinion / oil pump gears. \\ | + | |
- | Splash | + | |
- | * Cylinder walls | + | |
- | * Pistons, piston pins | + | |
- | * Cam gears and bushings | + | |
- | * Main bearings | + | |
- | + | ||
- | ==== Excess CC Pressure | + | |
- | See also [[techtalk: | + | |
- | Unvented crankcase | + | **Cold oil flows slower and at higher |
- | The pressure (even though needed) would build high enough to be detrimental | + | |
- | So unusable high pressure is vented out of the engine to keep in (regulate) a certain amount of usable internal pressure. \\ | + | |
- | ====== Oil Tank Pressure ====== | + | **The oil path, as designed, creates variable system pressures**. The restrictions in the oil feed path (hose size, routing paths, orifice sizes, etc) manipulate oil flow and oil pressure. Each restriction |
- | See the full article, [[techtalk: | + | |
- | There should not be any noticeable | + | |
- | **During normal operation**; | + | **Restrictions in the oil path harness and manipulate |
- | With the tank cap / dipstick removed, tank pressure is vented to atmosphere from the top of the tank. \\ | + | |
- | With the tank cap / dipstick installed, tank pressure is vented to the cam chest. \\ | + | |
- | **During shutdown**; \\ | + | **Oil volume to the motor is dependent on RPM**. When an engine is operated at higher speeds; the volume of oil circulated through |
- | The oil tank vent is connected to the cam chest and the cam chest is vented out the breather valve in the cam cover. \\ | + | |
- | So if you have pressure in your oil tank and the vent to the cam chest is not blocked then the cam chest is also pressurized. \\ | + | |
- | If the cam chest is holding pressure, then your breather valve can not be venting properly. \\ | + | |
- | Bottom line is that if the vent system | + | ==== Oil Pressure Light ==== |
+ | If the oil pressure light stays on at speeds above idling, always check the oil supply first. \\ | ||
+ | Then if the oil supply | ||
+ | If oil is returning to the tank, there is some circulation and the engine may be run a short distance if necessary. \\ | ||
+ | If no oil is returning, shut the engine off until the trouble is located and fixed. \\ | ||
+ | Conditions causing the oil light to stay on; \\ | ||
+ | Low or diluted oil supply, \\ | ||
+ | Or a plugged lifter screen (86-91) under the plug between the tappets, \\ | ||
+ | A grounded oil signal switch wire, \\ | ||
+ | Faulty oil switch, \\ | ||
+ | Faulty or weak oil pump, \\ | ||
+ | Clogged feed hose (in freezing weather from ice and sludge preventing the circulation of oil). \\ | ||
- | ====== | + | ===== Year Model Specifics |
- | ====== Oil Tank Capacity ====== | + | Refer to the drawings at the top of this page from the text below. \\ |
- | |1970-1978|3 quarts| | + | |
- | |1979-1981|4 quarts| | + | |
- | |1982-1985|3 quarts| | + | |
- | ====== Oil Filter ====== | + | |
- | |1970-E1980|Drop in element (63840)| | + | |
- | |L1980-E1984|Spin-on| | + | |
- | |L1984-1985|Spin-on| | + | |
- | ====== Oil Filter Mount ====== | + | ==== 1957-1976 |
+ | Oil pump feed gears send pressurized oil through a check ball mounted in the oil pump. Oil leaves the oil check and enters a hidden passage in the cam chest floor up through the cam cover internal passages to the pinion bushing / shaft. Oil is sent thru the pinion shaft to internal holes in the right flywheel to the crankpin and out to the lower end rod bearings. This is the end of oil pump pressure in the lower end. \\ | ||
- | See also [[techtalk: | + | Oil is also sent past the pinion bushing thru an internal passage in the cam cover to the upper feed galley in the top of the gearcase. There is a hole in the upper cover that opens to a horizontal drilled hole in the upper right case. Oil leaves the cam cover into the upper case galley and into 2 external oil lines attached on the top of the gearcase. Both oil lines are fed by the same "oil galley" |
- | **----- 1957-1978 XL - XLH Models -----** | + | ==== 1977-1985 ==== |
+ | Oil pump feed gerotors send pressurized oil through a check valve mounted in the oil pump. Oil leaves the oil check and enters a hidden passage in the cam chest floor up through the cam cover internal passages to the pinion bushing / shaft. Oil is sent thru the pinion shaft to internal holes in the right flywheel to the crankpin and out to the lower end rod bearings. This is the end of oil pump pressure in the lower end with the exception being 1985 models. Starting with crankcase number 785 303 002, manufactured after October 29, 1984, a spray tube was installed into the upper gearcase above the cams. The tube carries pressurized oil from the upper oil feed galley that exits out tiny holes in the tube to give the cams a constant spray of oil for extra cooling. \\ | ||
- | XLCH models did not have an oil filter. \\ | + | Oil is also sent up past the pinion bushing thru an internal passage in the cam cover to the upper feed galley in the top of the gearcase. There is a hole in the upper cover that opens to a horizontal drilled hole in the upper right case. Oil leaves the cam cover into the upper case galley and into 2 external |
- | XL / XLH models have an oil filter mounted inside | + | |
- | | 76 XLH filter in tank. ((photo by 4th of July of the XLFORUM http:// | + | ====== Oil Drainage ====== |
- | |{{:techtalk: | + | ===== Sub Documents ===== |
+ | * [[techtalk: | ||
- | **----- 1979 Models -----** | + | **Drain oil is not a part of the feed pressure system**. Drain oil is non-pressurized oil that exits the last orifice in the respective pressure path and eventually finds it way to the crankcase or cam chest floor awaiting to be scavenged by the oil pump. Once pressurized oil exits it's last orifice, pressure dissipates and is generally (at atmosphere) from there on. \\ |
- | 1979 models didn't come with an filter as a base sale from the MoCo. \\ | + | **Excess oil in the rocker boxes drains to the lower end**. Some drain oil from the rocker boxes falls to the crankcase by way of 2 drain holes in each head and cylinder while lubricating the cylinder walls, pistons, rings and main bearings. And some drain oil from the rocker boxes falls down the pushrod tubes, through channels in the lifter blocks to the gearcase compartment, |
- | However, an oil filter kit was debuted | + | |
- | So some may have them and others may have not. \\ | + | |
- | Oil filter mounting threads are M16 x 1.5mm. ((waiteitei of the XLFORUM http:// | + | |
- | **----- 1980-1981 Models -----** | + | **Drain oil is subject to the variable changing crankcase air pressure**. Drain oil aides in splash lube since some of that is picked up into air/oil mist and slung onto the moving parts by crankcase pressure pulses and the moving parts themselves. \\ |
- | The oil filter was relocated on 1980 and up models and they were fitted with an external | + | **There will always be an amount of oil left in the cases after shutdown**. A large portion of drain oil hits the bottom of the crankcase or cam chest and exits the motor by way of the oil pump and sent back to the oil tank during operation. During shutdown, there will be oil in the feed passages, up top in the boxes, on the flywheels and cams etc. that will fall back down to the gearcase and crankcase floors and will not be scavenged since the motor is not running. \\ |
- | The filter mount is located on a bracket between | + | |
- | It's under the seat in a awkward place to work with. ((MXHD55U of the XLFORUM http:// | + | |
- | Oil filter mounting threads are M16 x 1.5mm. ((waiteitei of the XLFORUM http:// | + | |
- | | Wide angle of filter location ((photo by Dutch Bobber | + | **There may also be a certain amount |
- | |{{: | + | |
- | |Oil filter mount on 81 model. | + | ====== |
- | |{{:techtalk: | + | ===== Sub Documents ===== |
+ | * [[techtalk: | ||
- | **----- 1982-E1984 Models -----** | + | ===== Role of Crankcase Pressure ===== |
+ | See also in the Sportsterpedia: | ||
+ | | ||
+ | | ||
- | The filter mount is mounted on the lower left front engine mount. \\ | + | **Positive crankcase pressure (piston downstroke) aides the scavenging ability of the pump**. Just like the feed side needs the positive push from gravity oil by way of the higher strung oil tank to operate efficiently, |
- | This has also been a popular practice on earlier bikes. \\ | + | [[techtalk:ref:oil21# |
- | | 82-E84 lower front motor mount / filter mount. ((photos | + | |
- | |{{:techtalk:ih:oil: | + | |
- | Oil filter mounting threads are M16 x 1.5mm. ((waiteitei | + | |
- | |Filter installed on an 80 XLH motor mount. | + | **Negative crankcase pressure |
- | |{{: | + | |
- | **----- L1984-1985 Models -----** | + | **1957-1976 engines**: \\ |
+ | **Positive crankcase pressure blows air and oil, from the crankcase, into the oil trough in the rear of the crankcase clear to the cam chest return cavity near the inlet side of the oil pump's return gears**. The crankcase, oil tank and gearcase all share the same air space so when one is pressurized, | ||
- | The oil filter on alternator ironheads is where the generator used to be. ((SHAKY DAVE of the XLFORUM http:// | + | **1977-Up engines**: \\ |
- | Two fittings | + | **Positive crankcase pressure |
- | Room was made there due to the new alternator location. \\ | + | |
- | This change was made along with the breather baffle tube assembly installed in the cam cover. \\ | + | |
- | The oil slinger system was eliminated. \\ | + | |
- | Oil filter mounting threads are 3/ | + | |
- | |{{: | + | ===== Role of the Oil Pump - Scavenge ===== |
+ | [[techtalk: | ||
- | |{{: | + | The scavenge side of the pump returns |
+ | Oil pump pressure and crankcase pressure work together to remove | ||
- | |{{: | + | == Oil pump suction == |
+ | Just as with the feed side, a vacuum is created on the inlet cavity of the return side generated by the opening of the gears (or gerotors respectively) as they rotate around to the inlet side of the pump. Pump vacuum is aided by the positive force of piston downstroke (57-76 in the gearcase, 77-85 in the crankcase) which serves as the NPSHA to the oil pump. On higher RPM, as the volume between the return gears/ | ||
+ | [[techtalk:ref:oil10# | ||
- | ====== Oil Filter Adapter (L84-85) ====== | + | == Oil pump pressure |
- | The threads on each end of the oil filter adapter are the same. \\ | + | **The oil pump pressurizes |
- | The I.D. on each end is also the same. \\ | + | One teeth cavity of oil at a time is rotated from the inlet side to the outlet side in the pump. The closing of the gear/gerotor teeth (respectively) afterward combined |
- | The adapter can be installed from either side as there is no check valve / check ball involved | + | |
- | **Installation**: | + | == Role of NPSHA to the oil pump== |
- | Thread | + | NPSHA is the (Net Positive Suction Head Available) to the oil pump and is needed to aid the oil pump's return side to function properly. Basically, the pump's ability to suck oil is lessened without |
- | However, a light coat of anti-seize would protect | + | |
- | Torque: 8-12 ft/lbs. ((1986-1990 HD Sportster FSM pg 3-42)) | + | |
- | **Dims**: \\ | + | ===== Return Oil Pressure / Volume ===== |
- | |{{: | + | Just like the feed side of the pump, the return side also is non-regulatory and delivers its entire volume of oil under pressure to the oil tank. Generally, pressure being exerted on the return path is not discussed in the FSM. However, return (drain) |
- | ====== Crankcase Oil Strainer (1957-1976) ====== | + | **Cold oil flows slower and at higher pressure than hot oil**. During start-up of a cold (ambient temp) engine, oil is thicker, oil pressure will be higher on the return path and oil circulation back to the tank will be somewhat restricted to flow within the return path. As the oil heats up it gets thinner, flows faster and pressure is lowered in the return path. \\ |
- | | + | **The return oil path, as designed, creates variable pressures between |
- | {{: | + | **Adding additional restrictions between |
- | ====== Engine Oil Cycle (1976 and Earlier) ====== | + | **Oil volume sent to the oil tank is dependent on RPM and the amount of oil available at the pump's return inlet.** When an engine |
- | + | ||
- | | + | |
- | * A check valve in the oil pump prevents the oil from draining into the engine by gravity. | + | |
- | | + | |
- | | + | |
- | * That is the vertical end of responsibility (pressure wise) for the oil pump. | + | |
- | * In the rocker boxes, oil gathers and splashes over rocker arm bearings and rods, valve stems, valve springs and pushrod sockets. | + | |
- | * Before the oil reaches the rocker lines, it splits off to a hole through the pinion shaft (to get to the rod bearings). | + | |
- | * This is the horizontal end of responsibility (pressure | + | |
- | * From here on, oil travels through the engine | + | |
- | * Oil drains from the heads through passages in each cylinder. | + | |
- | * Then it flows into two holes in the base of each cylinder while lubricating the cylinder walls, pistons, rings and main bearings.((1959-1964 HD Sportster FSM pg 3A-15)) | + | |
- | * Oil flows from the rocker boxes into the gearcase compartment through the pushrod tubes. | + | |
- | * Parts lubricated by this include the pushrods, tappets, tappet guides and tappet rollers and cam gears. | + | |
- | * Oil accumulated | + | |
- | * This splash | + | |
- | * Crankcase exhaust | + | |
- | * Gearcase oil flows through the fine mesh oil strainer preventing foreign particles from entering | + | |
- | * Engine oil returns to the oil tank by the scavenge side of the oil pump and also supplies oil to the rear chain oiler. | + | |
+ | ===== Crankcase Oil Removal ===== | ||
+ | === 1957-1976 engines === | ||
+ | **The crankcase is scavenged by positive crankcase air pressure (piston downstroke and flywheel rotation**. Positive crankcase air blows oil in the crankcase up into the oil trough in the rear of the crankcase. When pistons go down, oil is pushed into the oil trough and over to a sealed compartment (or oil trap) in the gearcase near timed breather gear on top of the oil pump. When the pistons go up, there is less push on the oil as upstroke begins sucking air up into the bottom of the pistons and less oil is dropped into the oil trough. The breather gear has " | ||
- | ====== | + | === 1977-1985 engines |
+ | **The crankcase is scavenged by oil pump suction assisted by positive crankcase air pressure**. Positive crankcase air (from piston downstroke and flywheel rotation) pushes oil in the crankcase | ||
- | * Oil is gravity fed to the gerotor type oil pump. Oil enters the feed section and fills a cavity under the feed pump. Oil is transferred from the inlet cavity to a one way check valve located in the outlet line. ((1970-1978 HD Sportster FSM pg 3-7)) | + | ===== Gearcase |
- | * The check valve prevents gravity oil drainage from the oil tank to the engine and acts as a restriction to activate the pressure switch. The check valve is set to open between 4 psi and 6 psi of oil pressure. ((1970-1978 HD Sportster FSM pg 3-7)) | + | === 1957-1976 engines === |
- | * As the oil pump pressurizes, | + | **Oil drained into the gearcase |
- | * Oil is routed to the crankshaft and to the head areas. Oil enters a hole in the pinion gear shaft and travels to the right flywheel then through the flywheel to the crank pin. Oil is forced out of the crank pin through 3 holes located to properly lubricate the rod bearing assembly. ((1970-1978 HD Sportster FSM pg 3-7)) | + | |
- | * Oil that bypasses the pinion gear shaft travels upward through the gearcase cover to the right crankcase and through | + | |
- | * Oil continues around a groove machined in the outside diameter of the large end of the rocker arm shaft and through | + | |
- | * Oil collected in the pushrod area of the heads flows down the pushrod covers to lubricate the lifters. The lifter' | + | |
- | * Oil collected in the valve spring pockets drains to the flywheel compartment through horizontal holes in the cylinders. Oil returning from the heads, rod assembly and gearcase collects in the sump area below the flywheels. ((1970-1978 HD Sportster FSM pg 3-5)) | + | |
- | * Oil collected in the sump area returns to the scavenger section of the oil pump through a passage located in the rear section of the pump. Oil flow to the pump is accomplished by the scavenger effect of the oil pump and the pressure created from the downward stroke of the pistons. ((1970-1978 HD Sportster FSM pg 3-7)) | + | |
- | * Return oil fills a cavity | + | |
- | * All engine breathing is accomplished through the gearcase | + | |
- | * Crankcase exhaust air is routed through a one way check valve to the air cleaner. | + | |
+ | === 1977-1985 engines === | ||
+ | **Oil drained into the gearcase is not scavenged by the oil pump but rather it drains into the crankcase by both gravity and crankcase vacuum**. The wall between the crankcase and gearcase has a drain hole near the bottom of the gearcase floor. Outside of gravity drain, piston downstroke (vacuum) aides in pulling oil from the gearcase into the crankcase where it gets blown to the timed breather along with crankcase air and oil. | ||
- | ===== Checking Oil Pressure | + | ====== Splash Lubrication ====== |
- | See also [[techtalk: | + | See also in the Sportsterpedia: |
+ | * [[techtalk: | ||
+ | * [[techtalk: | ||
- | When checking oil pressure, it's important to note that you are not testing pressure at a dead stop standpoint. \\ | + | Splash lubrication happens by way of crankcase air pulses and the spinning parts in the engine. \\ |
- | The oil is flowing into the engine | + | |
- | Likewise, the resulting pressure reading is a reflection of residual pressure while that pressure is being manipulated. \\ | + | |
- | (by oil flow as well as the current viscosity) | + | |
- | According | + | * **Crankcase air pressure is generated by the up and down movement of the pistons and carries splash oil to the cylinder walls, pistons, piston pins, cam bearings, cam gears and main bearings**. With little to no (piston ring) blow-by and a check valve on the breather system; crankcase pressure is essentially cycling between atmospheric and negative (pressures) as the pistons go down and back up (remember, due to the common crankpin 45 degree design, a Harley motor is a variable volume crankcase, unlike most motors) ((aswracing of the XLFORUM https:// |
- | The procedure is to take the oil pressure gauge off and install an oil gauge there. \\ | + | * The downstroke |
- | This works if you have verified | + | |
- | This takes the oil pressure | + | * Air/oil mist is accomplished by piston upstroke (vacuum) which brings smaller particles of oil up into and mixing with the air in the crankcase. The two don't actually mix as does sugar and water. So separating them back apart is fairly easy if you add an obstacle for that ' |
+ | * Excess CC Pressure is vented out of the engine: See Crankcase Ventilation in the link above. Excess unvented crankcase pressure will simply build up inside | ||
+ | * **There is no oil pump pressure in the crankcase or the gearcase/ | ||
- | However a tee can be added inline for a dedicated gauge. \\ | + | ===== Oil Lines to the Rockers ===== |
- | You can either mount a permanent gauge to the tap or plug it off until needed. \\ | + | There are rubber grommets on both ends of the oil lines. ((IronMick of the XLFORUM https:// |
- | This will keep the switch and the oil light inline | + | Some guys install two on each end, which is a wrong thing to do. \\ |
+ | Sometimes | ||
+ | Before going into the gearcase (to check for low / no oil to the rocker boxes); \\ | ||
+ | Remove both oil lines, | ||
- | {{: | + | | Oil line sleeves. ((photos |
- | ====== Low Oil Pressure ====== | + | |{{: |
- | The oil pressure light can fluctuate on and off for many reasons. \\ | + | |
- | It doesn' | + | |
- | However, it does warrant immediate concern and diagnosis. \\ | + | |
- | In fact, at idle, the oil pump check valve is barely opened past it's cracking pressure. Low revs at idle can cause the oil light to flicker off and on. \\ | + | |
- | A flickering light could be a loose or grounding switch wire, bad switch, oil too thin (viscosity breakdown), clearances in the oil pump worn and others. \\ | + | |
- | Don't assume the light or switch is bad. The job of the oil light and switch is to alert you of an oiling problem before it becomes a bigger problem. \\ | + | |
- | **First, check for oil return | + | ===== Cam Gear Oiler (1985 models only) ===== |
+ | Starting with crankcase number 785 303 002, manufactured after October 29, 1984, a cam gear oiler was installed | ||
+ | {{ pdf-bulletin: | ||
+ | This is a one year only addition. In 1986, the MoCo deleted | ||
+ | Then in 1992, they deleted | ||
+ | So the cam oiler tubing acts functions | ||
+ | The cam gear oiler directs over-pressured | ||
+ | Direct lubrication of the gear teeth allows tighter gear fitment. Gear backlash and noise are reduced. \\ | ||
- | **Check hoses and connections**: | + | |
- | * Check the return hose for kinks / cracks / damage and make sure the hose is tight with no leaks at all connections. \\ The inner lining of old or rotten hoses has also been known to collapse and block oil flow. | + | * There is an O-ring on the oiler tube nipple |
- | * Check the feed hose from the tank to the pump. \\ Visually inspect it for kinks / cracks / damage | + | * If the O-ring fails to seal the oiler tube, feed oil pressure |
- | * Verify the feed hose from the tank to pump will voluntarily flow oil out the lower end of the hose (pump inlet side). \\ Remove the hose at the pump only. \\ If no oil flows from gravity alone (and the tank has enough | + | |
- | * Verify that the oil tank vent is free and clear from blockage (allowing pressure to equalize in the tank). \\ Pull the vent line at the engine or cam chest respectively of year model. \\ Induce air into the line and check that the air is coming | + | |
- | **Check for oil flow from the pump both return and feed**: | + | |Cam oiler tube hole in gearcase. ((photo by Iron Mike of the XLFORUM, labeled by Hippysmack https://www.xlforum.net/forum/ |
- | * Check for flow out the return fitting at the pump. \\ Pull the return line from the engine | + | |{{: |
- | * Check for flow out the feed fitting at the pump. \\ Pull the oil switch from the pump. \\ Place a spare hose on the pump fitting and to a catch can. Then roll the engine over by hand and verify that oil will come out of the fitting. \\ If no oil at all comes out, then pull the pump and check for internal damage / blockage. \\ There probably won't be lot of flow, just verify the gears/ | + | |
- | **Verify that the oil pressure light is functioning properly**: \\ | + | ====== Oil System Controls ====== |
- | * Check for a loose or faulty connection at the oil pressure switch. \\ The wire connection at the oil pressure switch has to be tight so vibration won't cause intermittent signal loss to the oil light. | + | |
- | * Inspect the signal wire between the light and the pressure switch for kinks, cuts or faults. | + | |
- | * Make sure it's not grounding out on nearby metal parts (especially melted PVC jackets under wire ties). | + | |
- | * Run a continuity test on the entire length of wire with a multi-meter. | + | |
- | * Repair or replace the wire as needed. | + | |
- | * Verify that the light is not faulty or burnt out. | + | |
- | * Disconnect the wire at the oil pressure switch. | + | |
- | * Run a jumper wire off the (+) side of the battery to the end of the oil light wire. | + | |
- | * Verify it lights up and then bump the light by hand to verify vibration doesn' | + | |
- | **Verify that the oil pressure switch is working properly**: \\ The oil pressure switch is a spring loaded diaphragm. \\ With insufficient pressure pushing against the spring mechanism, the switch is normally grounded. \\ The switch grounds the circuit to the engine to make the light come on. \\ With adequate oil pressure against the spring, the circuit contact is broken which turns off the oil light. \\ [[techtalk: | + | ===== Transfer Valve (76 and earlier) ===== |
+ | ==== Sub Documents ==== | ||
- | **Check | + | |
- | * [[techtalk:ref:oil04|Click Here]] to view the page in the REF section on expected oil pressure for 1957-up Sportsters. \\ For Ironheads, testing at the rocker boxes will give you lower pressure on the gauge and cannot be used for overall oiling system health. \\ Be sure to check pressure at the oil pump, not the rocker boxes. | + | * [[techtalk:ih:oil01u|Plugging the Transfer Valve]] |
- | * The pressure reading is directly tied to the flow rate. More flow = more gauge pressure, Less flow = less gauge pressure. | + | * [[techtalk:ih:oil01v|Removing / Installing the Transfer Valve]] |
- | * If you have 6 PSI on cold start at the heads, you have more than that at the oil pump. | + | |
- | * [[techtalk:ref:oil15|Click Here]] to view " | + | |
- | **A faulty oil pump check ball / valve spring in the pump may not turn off the oil light**: \\ | + | The transfer |
- | * On 1957-1976 models, verify correct oil check ball spring pressure | + | It was installed |
- | * If the check valve spring pressure is changed with a stiffer spring or if the spring has been stretched (extended), \\ The oil pump may not make sufficient oil pressure to overcome the spring pressure at warm idle. \\ The oil light may stay on until higher RPM raises oil pressure enough to overcome | + | [[techtalk: |
- | * On 1977-1985 models, the restricted orifice in the check valve in the pump creates back pressure to actuate the oil pressure switch. \\ | + | |
- | * If the check valve is stuck in the open position; | + | |
- | * The oil still has to travel through the restricted orifice in the check which creates backpressure to actuate the pressure switch → oil light. | + | |
- | * If the check valve was stuck in the closed position; | + | |
- | * Pressure would still build up inside the oil pump and actuate the oil pressure switch and then the oil light. \\ This would seem like everything is fine with the engine running and the light off. \\ However, with the check closed, no oil would enter the engine. | + | |
- | * To check for a stuck closed check valve, remove oil the pump and cover, push a small screwdriver or suitable metal rod into check valve opening. \\ The valve should be closed and the rod should push back on the internal spring with ease. \\ If it is stiff, remove the check from the pump body and then remove it's O-ring seal. \\ Soak it in solvent while pushing in and working | + | |
- | | + | |
- | **Check for other possible causes of low oil pressure**: \\ | + | The transfer valve (25075-55) is installed in the left case between |
- | * If the tank is empty, obviously oil pressure will be low. Do not check oil level with a cold engine (operating temp only) | + | There is only one moving part in the transfer valve assembly which is the triangular shaped disc in the pics below. \\ |
- | * The oil filter | + | **Dims**: The valve disc is a triangular piece of .009" thick stainless steel that can move about .015" left to right in the valve assembly. \\ |
- | * There has been occasions where silicon (placed on the oil pump gasket during installation) had made it's way into orifices inside | + | The ID of the thru hole of the assembly is .097". ((needspeed |
- | * No oil to the top end (1957-1976): | + | In a running engine, it is a one way valve that lets air and oil pass through it from primary case to flywheel case. \\ |
- | * Make sure the rubber grommets on each end of the stock rocker feed lines are not partially plugging the ends of the rocker feed lines. \\ Then remove the allen-hex rocker spindle plug from the front exhaust rocker spindle, at the right-hand side of the rocker box. \\ Oil should come out there if you have flow with the engine running. | + | |
- | * You can loosen or remove the 1/8" NPT pipe plug from the right side, front corner of each rocker cover. \\ With the engine at idle, you should get a small amount of oil plopping out (not shooting out like a fire hose). ((IronMick of the XLFORUM http://xlforum.net/ | + | |
- | * You can also use the same 1/8" plug hole to install a barb and clear hose to visually inspect for oil flow. \\ {{: | + | |
- | * Check the pinion shaft to bushing clearance to the specs in the FSM. \\ If the fit is overly loose, this condition will not allow oil to be transferred up the lines at low speed. \\ Oil will just be bled out into the cam chest until RPM sends and over-runs more oil than can be spilled at the bushing. | + | |
- | * If the fit is out of spec, you'll need to replace | + | |
- | * Then line ream it using a special reamer through an old right-hand crankcase half to use to guide to get it in square. | + | |
- | * On 76< motors, it's best to eliminate | + | |
- | * The oil pump could be weak or malfunctioning. | + | The video below was made by XLForum member, Harton, and shows how the transfer valve will move oil out of the primary into the crankcase. \\ |
- | * 76< pumps: | + | But this is not indicative to true vacuum inside as the oil it's removing adds to engine vacuum until after the oil is removed. ((video courtesy of harton |
- | * If the pump shaft seal is blown, then the scavenge pump will continue | + | {{ video: |
- | **Remove | + | The source for transfer is not the valve but rather piston upstroke. \\ |
- | The oil pump supplies pressurized oil into a hole in the cam cover. \\ | + | Positive crankcase pressure pushes the valve disc to the left and seals a small hole preventing flow into the primary. \\ |
- | That pressurized | + | Vacuum in the crankcase pulls the disc to the right up against a stop that has a larger hole. \\ |
- | That is the vertical end of responsibility (pressure | + | The 3 cuts that make the disc a triangle shape allows air/oil to flow around it into the crankcase. \\ |
- | Before | + | |
- | This is the horizontal end of responsibility | + | Without the engine running and with no spring to maintain |
+ | On engine start up the excess | ||
+ | |||
+ | < | ||
+ | This valve largely seals by dynamic action (aka windage) from the down stoke of the pistons. The disk is only a marginal seal at static, and yes it will leak. \\ | ||
+ | An engine will produce more HP if there is a slight vacuum in the crankcase as it does not have to over come pressure. \\ | ||
+ | However, excess vacuum can cause problems in scavenging the oil from the crankcase. \\ | ||
+ | This valve lets a controlled amount of air into the crankcase. \\ | ||
+ | Crankcase vapor and oil is sent through the timed breather valve on downstroke along with any oil that has gotten over the disk level when parked. \\ | ||
+ | The flow is not from the crankcase to the primary. There is no advantage to removing the transfer valve. \\ | ||
+ | The transmission on the models that use it are designed | ||
+ | Blocking it and going with gear oil can cause problems down the road if your crankcase fills up with oil. \\ | ||
+ | You can always tell when the crankcase has excess | ||
+ | You can also notice a reluctance in the engine wanting to run up as it is churning all of that excess oil around draining | ||
+ | The excess oil in the primary will be scavenged back to the engine through this valve. \\ | ||
+ | Note: on race engines, it is imperative | ||
+ | Not only can it rob HP but it can also cause crank deflection and failure. \\ | ||
+ | </ | ||
+ | See Further Study of the Transfer Valve Operation and Affects of Plugging the Valve above. \\ | ||
+ | |||
+ | The transfer valve is staked into position. ((Ferrous Head of the XLFORUM https:// | ||
+ | Look very close around the edges and you'll see two spots that have been lightly punched. \\ | ||
+ | |||
+ | |{{: | ||
+ | | Transfer valve ((photo by FourCams of the XLFORUM https:// | ||
+ | |||
+ | The thread pattern | ||
+ | There is nothing to wear out. However anything that stops the movement | ||
+ | The one taken apart here was gummed up with old oil that had a tar like consistency. \\ | ||
+ | |||
+ | {{: | ||
+ | |||
+ | Also, as a test, a container of 20w-50 oil at room temperature was allowed to gravity drain from the transfer valve. \\ | ||
+ | It took 48 hours for 100 milliliters of oil to drip through | ||
+ | |||
+ | {{: | ||
+ | |||
+ | Here are a few drawings detailing the assembly: \\ | ||
+ | |||
+ | {{: | ||
- | With this pressure comes a certain amount of oil flow from the oil pump. \\ | ||
- | With a weak oil pump, there will be less pressure forced up the oil lines. \\ | ||
- | This will result in less oil reaching the rockers. \\ | ||
- | But, not necessarily less oil reaching the rod bearings (depending on degree of pump pressure reduction). \\ | ||
- | How much oil loss to the rockers is acceptable is yet to be determined. \\ | ||
- | However, the MoCo had to have accounted for a certain amount of pressure loss from the pump during the engineering phase. \\ | ||
- | But, the service limit for oil pressure was not detailed in the FSM. \\ | ||
===== Oil Pressure Switch ===== | ===== Oil Pressure Switch ===== | ||
- | See also in the Sportsterpedia: | + | ==== Sub Documents ==== |
+ | * [[techtalk: | ||
+ | |||
+ | See also in the REF section of the Sportsterpedia: | ||
* [[techtalk: | * [[techtalk: | ||
* [[techtalk: | * [[techtalk: | ||
- | |||
- | {{ : | ||
The oil pressure switch (for the oil light) is a pressure actuated diaphragm type on / off switch basically. \\ | The oil pressure switch (for the oil light) is a pressure actuated diaphragm type on / off switch basically. \\ | ||
Line 410: | Line 343: | ||
However, hot idle oil pressure will vary from 3-7 PSI. \\ | However, hot idle oil pressure will vary from 3-7 PSI. \\ | ||
__So, at idle, the oil pump check valve is barely opened past it's cracking pressure__ (not to it's end of travel). \\ | __So, at idle, the oil pump check valve is barely opened past it's cracking pressure__ (not to it's end of travel). \\ | ||
- | |||
- | **In the Case of a Defective Oil Pump Switch**: \\ | ||
- | This switch opens and closes the contacts to the oil pressure light. \\ | ||
- | The oil light is important to have since if it is not working, it can be assumed that you have little to none oil flow to the engine. \\ | ||
- | If the pressure switch doesn' | ||
- | For the $30 or whatever you save by not buying the switch, it's just not worth it to not have the low engine pressure idiot light working. ((billeuze of the XLFORUM http:// | ||
- | If your motor is ready to run and you need to test it then you can connect a piece of clear hose so you can see oil in it. \\ Don't plug the end till you've primed the pump (with ignition off kick it over a few times until oil comes out the clear pipe where the pressure switch lives). \\ | ||
- | Replace a defective switch as soon as possible. \\ | ||
- | |||
- | * If the pressure switch is stuck in the closed position; \\ The circuit stays grounded with the engine running and the light stays on. \\ Hardened oil goop around the end of the switch can possibly block oil pressure from opening the switch. | ||
- | * If the pressure switch is stuck in the open position; \\ The circuit will stay open with the engine running or not. \\ The light will not come on during startup or alert you of low oil pressure during engine operation. | ||
**Oil Pressure Switch Pics** \\ | **Oil Pressure Switch Pics** \\ | ||
Line 428: | Line 350: | ||
===== Oil Pump Check Valve ===== | ===== Oil Pump Check Valve ===== | ||
+ | ==== Sub Documents ==== | ||
+ | * [[techtalk: | ||
+ | See also in the Sportsterpedia; | ||
+ | [[techtalk: | ||
- | **The oil pump check valve plays a role in the operation of the oil pressure switch**. \\ | + | **The oil pump check valve plays a role in the operation of the oil pressure switch**. \\ |
+ | It adds additional restriction in the feed path which raises the oil pressure in the chamber feeding the switch. \\ | ||
{{: | {{: | ||
- | The check valve is not a pass through but instead a cartridge type one way check valve operated by a spring loaded cup against a seat pressing at 4-6 PSI. \\ | + | The check valve is not a pass through but instead a cartridge type one way check valve operated by a spring loaded cup against a seat pressing at 4-6 PSI. Oil pressure enters the center of the check valve, lifts the cup against its spring and exits the check valve by pushing around and past the cup and into the engine. At a point, the cup will float off it's seat up against the spring towards the end of it's travel. \\ |
- | Oil pressure enters the center of the check valve, lifts the cup against its spring and exits the check valve by pushing around and past the cup and into the engine. | + | |
- | At a point, the cup will float off it's seat up against the spring towards the end of it's travel. \\ | + | |
According to the FSM, the check valve has two main functions; \\ | According to the FSM, the check valve has two main functions; \\ | ||
Line 441: | Line 366: | ||
It also acts as a restriction to activate the oil pressure switch.\\ | It also acts as a restriction to activate the oil pressure switch.\\ | ||
- | Without the check valve, the pressure would not build up as much in the ' | + | Without the check valve, the pressure would not build up as much in the ' |
- | It would free flow into the crankcase and disperse. | + | |
- | With the check valve installed and the oil having to find it's way around the cup, pressure builds behind it in the pocket. | + | |
- | This back pressure builds inside the pump and pushes the pressure switch contacts open, shutting off the oil light. \\ | + | |
- | The check valve spring does not control the amount of oil that enters the engine (unless it's stuck closed). | + | The check valve spring does not control the amount of oil that enters the engine (unless it's stuck closed). The flow goes past the check no matter what. The spring pressure is very light. It regulates (creates and manages) the oil pressure in the pocket next to the switch before it enters the engine. That pocket is protected for one reason (to operate the oil switch, therefore the oil light). If you are not running an oil light, there is no reason to be concerned with the check valve (in regards to a running engine). You could remove the light and the check and it would not affect the oil flow thru the engine. The positive displacement oil pump will still deliver oil. \\ |
- | The flow goes past the check no matter what. The spring pressure is very light. | + | |
- | It regulates (creates and manages) the oil pressure in the pocket next to the switch before it enters the engine. | + | |
- | That pocket is protected for one reason (to operate the oil switch, therefore the oil light). | + | |
- | If you are not running an oil light, there is no reason to be concerned with the check valve (in regards to a running engine). | + | |
- | You could remove the light and the check and it would not affect the oil flow thru the engine. | + | |
- | The positive displacement oil pump will still deliver oil. \\ | + | |
The check/ | The check/ | ||
- | In theory and design, if the pressure in the pocket is low, oil flow would also be low. \\ | + | In theory and design, if the pressure in the pocket is low, oil flow would also be low. In practice, there are too many variables on a worn engine, |
- | In practice, there are too many variables on a worn engine, | + | |
- | The cup will stay off it's seat and open as long as there is sufficient oil pressure pushing against its spring. | + | The cup will stay off it's seat and open as long as there is sufficient oil pressure pushing against its spring. This spring actuates the 4-6 PSI pressure that the pump must overcome. If there is not enough oil pressure coming from the pump to keep the check valve cup completely or partially off it's seat; The back pressure from the spring will push the cup toward it's seat, or closed position, equal to the amount of minimum pressure loss from the pump. Thinner (hotter) oil flows faster and builds less pressure. \\ |
- | This spring actuates the 4-6 PSI pressure that the pump must overcome. | + | |
- | If there is not enough oil pressure coming from the pump to keep the check valve cup completely or partially off it's seat; \\ | + | |
- | The back pressure from the spring will push the cup toward it's seat, or closed position, equal to the amount of minimum pressure loss from the pump. \\ | + | |
- | Thinner (hotter) oil flows faster and builds less pressure. \\ | + | |
- | When the oil thins out, the oil pressure will still try to push past the cup. \\ | + | When the oil thins out, the oil pressure will still try to push past the cup. At a point, the pressure from the pump may not be sufficient to completely float the cup off it's seat. So, the cup will turn sideways a bit only allowing oil to pass it on one side. \\ |
- | At a point, the pressure from the pump may not be sufficient to completely float the cup off it's seat. \\ | + | |
- | So, the cup will turn sideways a bit only allowing oil to pass it on one side. \\ | + | |
{{: | {{: | ||
- | This reduction in pressure is also sensed by the oil pressure switch. | + | This reduction in pressure is also sensed by the oil pressure switch. When the pressure drops, the diaphragm eases back toward the closed position. If the pressure is low enough, the contacts will close or partially make contact while closing or intermittently opening and closing. The oil light will come on or flicker depending on the action of the contacts. \\ |
- | When the pressure drops, the diaphragm eases back toward the closed position. | + | |
- | If the pressure is low enough, the contacts will close or partially make contact while closing or intermittently opening and closing. | + | |
- | The oil light will come on or flicker depending on the action of the contacts. \\ | + | |
- | The pressure switch requires no back pressure from the engine to stay open.\\ | + | The pressure switch requires no back pressure from the engine to stay open. It opens solely from the pressure generated from the oil pump with the assistance of the check valve to hold some of that pressure in the pump. \\ |
- | It opens solely from the pressure generated from the oil pump with the assistance of the check valve to hold some of that pressure in the pump. \\ | + | |
- | So, it is possible but not likely to have a stuck closed check valve with no oil light on. \\ | + | |
- | ====== Top End Oiling ====== | + | ===== Rear Chain Oiler (1957-1976) |
- | ===== Cam Cover Oiling ===== | + | ==== Sub Documents |
- | The oil going up to the top end not only passes by the bushing in the cam chest, but also is fed to and from the cam cover and through the cam cover gasket. ((XLFREAK of the XLFORUM http:// | + | * [[techtalk:ih: |
- | It is possible for the gasket to blow out and seal up the oil galley feed passages. \\ | + | * [[techtalk: |
- | Also if silicon was used on the cover, it is possible for that to break loose and stop up the passages. \\ | + | * [[techtalk:ih: |
- | You can take the cover off and run a tap down all the threaded holes to clear out any obstructions. \\ | + | |
- | Also check that the face of the cover and case are not marred by some big scratch or dent. \\ | + | |
- | To get old silicone out of bolt holes, you can use an inflation needle for footballs/ | + | |
- | Cut the tip off of it then screw it into the end of an air blowgun. \\ | + | |
- | It's narrow enough that it doesn' | + | |
- | |Oil path of 85 style cam cover ((photo by billeuze | + | The chain oiler is not part of the feed pressure system. It is tapped off the return oil system and is a designed leak to keep the chain from rusting up. There is a factory adjusting screw to control the amount |
- | |{{: | + | |
- | ===== Oil Lines to the Rockers ===== | + | **Location**: |
- | There are rubber grommets on both ends of the oil lines. ((IronMick | + | The chain oiler fitting is either located behind the sprocket cover or at the oil tank respectively |
- | Some guys install two on each end, which is a wrong thing to do. \\ | + | * **1954-1966 KH, XL and XLH** used a (63607-53) NPT x compression tubing x SAE threaded regulating fitting. |
- | Sometimes the rubber from an improperly installed grommet plugs the oil line. \\ | + | * **1958-1969 XLCH** used a (63601-54) NPT x SAE x 1/4" hose bibb regulating fitting mounted to the oil tank. |
- | Before going into the gearcase | + | * (63611-53), chain oiler upper hose bracket mounts to the top of the case under the (R) motor mount bolt. |
- | Remove both oil lines, | + | * (63612-53), chain oiler lower hose bracket mounts |
+ | * **1967-E1972 XLH and 1970-E1972 XLCH** used a (63595-67) hex body flared connection regulating fitting with a mounting tab to the top of the motor behind the rear sprocket. | ||
+ | * **L1972-1976 XLH and XLCH** used a (63595-72) updated hex body flared connection regulating fitting with a mounting tab to the top of the motor behind the rear sprocket. | ||
- | | Oil line sleeves. ((photos by sc72 of the XLFORUM http:// | + | **Installed Pics**: \\ |
- | |{{: | + | |
- | ===== Rocker Box ===== | + | |
- | The feed to the rockers is not a large diameter passage and not a lot of oil goes to the rocker gear. ((Ferrous Head of the XLFORUM http:// | + | |
- | But if you pull the lines off with the engine running you should be getting a good steady flow out of them. \\ | + | |
- | ====== Bottom End Oiling ====== | + | Below is a L1962-1965 XLCH " |
+ | The blue line is the oil level. The red line is a tube inside the tank. The bottom of that tube feeds the lower (chain oiler) fitting. \\ | ||
+ | The top of the tube is open and above the oil level. So, nothing drains out of the bottom fitting if you open it. \\ | ||
+ | Note the open top of red tube is directly below the return fitting. \\ | ||
+ | When the bike is running, return oil spills into the red tube to supply the chain oiler fitting installed in the lower port. \\ | ||
+ | This feeds chain only when the engine is running and doesn' | ||
+ | {{: | ||
- | ===== Cam Gear Oiler (1985 models only) ===== | + | | Chain Oiler Piping on 74 XLCH ((photo by K Beggs of the XLFORUM https:// |
+ | |{{: | ||
- | Starting with crankcase number 785 303 002, manufactured after October 29, 1984, a cam gear oiler was installed in the gearcase ceiling. ((HD TSB #M-899 dated November 30, 1984)) \\ | + | ====== Oil Filter Mount ====== |
- | {{ pdf-bulletin:tsb0899.pdf | + | See also [[techtalk:ref:oil13|Remote Oil Filters]] |
- | This is a one year only addition. In 1986, the MoCo deleted the tubing and installed a pressure bypass on the oil filter pad. \\ | + | \\ |
- | Then in 1992, they deleted | + | |
- | So the cam oiler tubing acts functions for cam lubrication as well as a high pressure release for the upper oil feed galley. \\ | + | |
- | The cam gear oiler directs over-pressured oil from the upper feed galley to the gear mesh between the cams with 4 small holes in the tubing. \\ | + | |
- | Direct lubrication of the gear teeth allows tighter gear fitment. Gear backlash and noise are reduced. | + | |
- | | + | **----- 1957-1978 XL - XLH Models -----** |
- | | + | |
- | * If the O-ring fails to seal the oiler tube, feed oil pressure to the top end could be low. | + | |
- | |Cam oiler tube hole in gearcase. ((photo by Iron Mike of the XLFORUM, labeled by Hippysmack http:// | + | XLCH models did not have an oil filter. \\ |
- | |{{: | + | XL / XLH models have a "drop in" oil filter mounted inside |
+ | | 76 XLH filter in tank. ((photo by 4th of July of the XLFORUM https:// | ||
+ | |{{: | ||
- | ====== Transfer Valve (76 and earlier) ====== | + | **----- 1979 Models -----** |
- | ===== Sub Documents ===== | + | |
- | * [[techtalk: | + | 1979 models didn't come with an filter as a base sale from the MoCo. \\ |
- | * [[techtalk:ih: | + | However, an oil filter kit was debuted in 79 as an accessory item. \\ |
+ | So some may have them and others may have not. \\ | ||
+ | Oil filter mounting threads are M16 x 1.5mm. ((waiteitei | ||
- | The transfer valve is not the crankcase vent (aka foo-foo valve). The crankcase vent fitting wasn't used until the 1977 model year. \\ | + | **----- 1980-1981 Models -----** |
- | It was installed in 77-78 engines only in the cam cover and vents crankcase pressure (air) to atmosphere. \\ | + | |
- | [[techtalk: | + | |
- | The transfer valve (25075-55) is installed in the left case between the primary | + | The oil filter was relocated on 1980 and up models and they were fitted with an external "spin-on" oil filter. \\ |
- | There is only one moving part in the transfer valve assembly which is the triangular shaped disc in the pics below. \\ | + | The filter mount is located on a bracket |
- | It's a triangular piece of .009" thick stainless steel that can move about .015" left to right in the valve. There is no spring. \\ | + | It's under the seat in a awkward place to work with. ((MXHD55U |
- | In a running engine, it is a one way valve that lets air and oil pass through it from primary case to flywheel case. \\ | + | Oil filter mounting threads are M16 x 1.5mm. ((waiteitei of the XLFORUM https://www.xlforum.net/ |
- | The video below was made by XLForum member, Harton, and shows how the transfer valve will move oil out of the primary into the crankcase. \\ | + | | Wide angle of filter location ((photo |
- | But this is not indicative to true vacuum inside as the oil it's removing adds to engine vacuum until after the oil is removed. \\ | + | |{{:techtalk:ih: |
- | {{ :video:1974_ironhead_transfer_valve_test_by_harton.mp4 |1974 IRONHEAD Transfer Valve Test by Harton}} \\ | + | |
- | The source for transfer is not the valve but rather piston upstroke. \\ | + | |Oil filter mount on 81 model. ((photos by motorhedmike of the XLFORUM https://www.xlforum.net/ |
- | Positive crankcase pressure pushes the valve disc to the left and seals a small hole preventing flow into the primary. \\ | + | |{{: |
- | Vacuum | + | |
- | The 3 cuts that make the disc a triangle shape allows air/oil to flow around it into the crankcase. \\ | + | |
- | Without the engine running and with no spring to maintain a tight seal, oil can slowly leak through and let wet sumped oil pass into the primary. \\ | + | **----- 1982-E1984 Models -----** |
- | On engine start up the excess oil in the primary should be transferred back into the engine. \\ | + | |
- | < | + | The filter mount is mounted on the lower left front engine |
- | This valve largely seals by dynamic action (aka windage) from the down stoke of the pistons. The disk is only a marginal seal at static, and yes it will leak. \\ | + | This has also been a popular practice on earlier bikes. \\ |
- | An engine will produce more HP if there is a slight vacuum in the crankcase as it does not have to over come pressure. \\ | + | | 82-E84 lower front motor mount / filter mount. ((photos by DirtyCory |
- | However, excess vacuum can cause problems in scavenging the oil from the crankcase. \\ | + | |{{: |
- | This valve lets a controlled amount of air into the crankcase. \\ | + | Oil filter mounting threads |
- | Crankcase vapor and oil is sent through the timed breather valve on downstroke along with any oil that has gotten over the disk level when parked. \\ | + | |
- | The flow is not from the crankcase to the primary. There is no advantage to removing the transfer valve. \\ | + | |
- | The transmission on the models that use it are designed for engine oil. \\ | + | |
- | Blocking it and going with gear oil can cause problems down the road if your crankcase fills up with oil. \\ | + | |
- | You can always tell when the crankcase has excess oil as the rear cylinder will usually smoke until the oil is scavenged out. \\ | + | |
- | You can also notice a reluctance in the engine wanting to run up as it is churning all of that excess oil around draining off HP. \\ | + | |
- | The excess oil in the primary will be scavenged back to the engine through this valve. \\ | + | |
- | Note: on race engines, it is imperative to not allow oil to hit the crank and that is why windage trays and baffled | + | |
- | Not only can it rob HP but it can also cause crank deflection | + | |
- | </blockquote> | + | |
- | See Further Study of the Transfer Valve Operation and Affects of Plugging the Valve above. | + | |
- | The transfer valve is staked into position. ((Ferrous Head of the XLFORUM | + | |Filter installed on an 80 XLH motor mount. ((photo by hscic of the XLFORUM |
- | Look very close around | + | |{{: |
+ | **----- L1984-1985 Models -----** | ||
- | |{{: | + | The oil filter on alternator ironheads is where the generator used to be. ((SHAKY DAVE of the XLFORUM |
- | | Transfer valve ((photo by FourCams | + | Two fittings |
+ | Room was made there due to the new alternator location. \\ | ||
+ | This change was made along with the breather baffle tube assembly installed in the cam cover. \\ | ||
+ | The oil slinger system was eliminated. \\ | ||
+ | Oil filter mounting threads are 3/4"-16. \\ | ||
+ | |{{: | ||
- | The thread pattern is 3/4"-16. ((needspeed of the XLFORUM http://xlforum.net/ | + | |{{: |
- | There is nothing to wear out. However anything that stops the movement of the reed (rust or dirt) means the valve won't work. \\ | + | |
- | The one taken apart here was gummed up with old oil that had a tar like consistency. \\ | + | |
- | {{: | + | |{{: |
- | Also, as a test, a container of 20w-50 oil at room temperature was allowed to gravity drain from the transfer valve. \\ | + | ====== Oil Filter Adapter (L84-85) ====== |
- | It took 48 hours for 100 milliliters of oil to drip through | + | The threads on each end of the oil filter adapter are the same. \\ |
+ | The I.D. on each end is also the same. \\ | ||
+ | The adapter can be installed from either side as there is no check valve / check ball involved with the oil filter mount. \\ | ||
- | {{:techtalk: | + | **Installation**: \\ |
- | + | Thread | |
- | Here are a few drawings detailing | + | However, a light coat of anti-seize would protect |
- | + | Torque: 8-12 ft/lbs. ((1986-1990 HD Sportster FSM pg 3-42)) \\ | |
- | {{: | + | |
- | + | ||
- | + | ||
- | ===== Removing / Installing the Transfer Valve ===== | + | |
- | + | ||
- | The transfer valve is staked into place and it is steel into alloy which is always problematic. ((Ferrous Head of the XLFORUM http:// | + | |
- | If you do remove/ | + | |
- | + | ||
- | * You can use a hammer and punch to stake mark out of the valve slot. Be careful when hammering on your cases. ((Dr Dick of the XLFORUM http:// | + | |
- | * You can find a socket that same size as the OD of the valve. | + | |
- | * You can use a Snap-On Drag Link socket to remove the transfer valve. ((The Doctor71 of the XLFORUM http:// | + | |
- | + | ||
- | |Special tool to remove / install transfer valve. ((photo by Ferrous Head of the XLFORUM http:// | + | |
- | |{{: | + | |
- | + | ||
- | ---- | + | |
- | + | ||
- | + | ||
- | ====== Wet Sumping ====== | + | |
- | See article on [[techtalk: | + | |
+ | **Dims**: \\ | ||
+ | |{{: | ||
\\ | \\ | ||
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