Differences

This shows you the differences between two versions of the page.

--- techtalk:evo:oil06 [2019/10/13 04:05]
hippysmack [Oil Leaks]
+++ techtalk:evo:oil06 [2019/10/13 23:46]
hippysmack [Check intake and exhaust ports in the heads]
@@ Line 3: / Line 3: @@
 ====== Oil Leaks ======
-**First and foremost, do not use silicone on any engine, oil pump or related parts or gaskets**. \\
+**First and foremost, do not use silicone sealer on any engine, oil pump or related parts or gaskets to stop a leak**. \\
-The heat coupled with crankcase pressure pulses will break it loose. \\
+The heat coupled with crankcase pressure pulses can break pieces of it loose and send them through the engine. \\
 These pieces may stop up oil passages and starve the engine of oil. \\
 The gaskets / seals made for Sportsters are more than efficient for stopping leaks. \\
@@ Line 10: / Line 10: @@
 There may be manufacturing, fitting, high internal pressure pulses, warped sealing surfaces or other issues to address. \\
+Silicone can break up into small film sheets and float around the oil path stopping up the small restricted passages. \\
+Both feed and return sides of the oil pump create suction on their inlet sides as they rotate. \\
+The feed side of the pump is gravity fed from the tank and the feed gerotors send pressure into the engine. \\
+It is mainly dependent on gravity oil from the tank. \\
+The scavenge side of the pump is fed by crankcase pressure pushing the oil to the scavenge port in the crankcase. \\
+It is more dependent on the flywheels to get the oil to the scavenge port. \\
+If there is an obstruction in the return path from the crankcase to the oil tank, it will slow the flow of oil out of the engine. This can cause weak or no oil flow. \\
+If the scavenge side of the oil pump is not flowing oil fast enough to the tank, oil will build up in the sump. \\
+This can result in higher crankcase pressure, more oil film spinning around the flywheels, engine drag, blowing rocker box gaskets and general oil leaks. \\
+In an instance where used silicone was used to seal the gaskets, pieces of silicone (or sheets) could be sucked in, stretched and broke off into the engine. \\
+This silicone 'gummy bear' sheet was found in the oil pump. \\
+{{:techtalk:evo:oil:oil_pump_damage_3_by_-_-_-_annotated.jpg?direct&300|}} ((photo by (-_-) of the XLFORUM, annotated by Hippysmack http://xlforum.net/forums/showthread.php?t=2074835&page=3)) \\
+An oil leak could also be a crankcase pressure problem. A situation where the engine is both blowing out and then pulling in air from the rocker box gaskets. \\
+-up engines seem to be more susceptible to crankcase pressure problems. \\ It's important to inspect and change out the breather valves periodically. Read more about the [[techtalk:evo:oil06#check_the_breather_valves_umbrellas|breather valves]] below. \\
 ====== Oil Consumption Service Bulletin - August 10, 2005 ======
 Article by Krayven Sumhead of the XLFORUM ((http://www.xlforum.net/forums/showthread.php?p=174442#post174442))
@@ Line 56: / Line 71: @@
 ====== Diagnosing Oil Leaks ======
+Obviously you must find exactly what is leaking before you can determine what will be needed to fix it. ((santis5 of the XLFORUM http://xlforum.net/forums/showthread.php?t=615245)) \\
+Degrease the area in question and run the bike a little and watch the area for the beginning signs of seepage. \\
+Check torque on the bolts on covers and parts with gasket/seals but do not tighten more than the specs in the FSM to stop a leak. \\
+That may result in stripping the threads. \\
+If you have a gasket / seal that has needed replacing several times,  you must find the cause of the continued failure and then repair that. \\
+In some cases, a considerable amount of the engine has to be disassembled just to get to the problem. Refer to your FSM for the proper procedures. \\
+Always keep a close watch on oil levels if you know you have a leak. \\
+===== Overfilled Oil Tank =====
+Read more on [[techtalk:ref:oil01#overfilling_the_oil_tank|Overfilling the Oil Tank]] in the REF section of the Sportsterpedia. \\
+Before topping off the oil tank, run the engine if possible for about a 30 min. ride. \\
+This heats up the oil to operating temperature and suspends the solids in the oil instead of it laying on the bottom of the case. \\
+This also allows the oil pump to send most of the oil in the engine back to the tank before you add more so you get a more accurate account of the oil level. \\
+Failure to warm the engine first can result in an overfull condition in the system and you can end up blowing the cap off the oil tank and a big mess. \\
+Overfilling your oil tank can also result in engine drag (wetsumping) and puking oil out the air cleaner. \\
+The oil tank is vented to the gearcase / cam chest in the engine using a stand pipe in the oil tank. \\
+When the tank is slightly over filled, oil that was standing in the sump is added to the tank via the oil pump, thus raising the level in the tank. \\
+The excess oil in the tank will either flow back into the gearcase via the tank vent or up and out of the oil cap. \\
+Excess oil that returns to the gearcase through the tank vent is picked up with crankcase air pressure and blown out the engine breather valve(s). \\
+So, depending on your venting setup, oil can be blown into the air cleaner or out the vent lines due to overfilling the oil tank. \\
 ===== Visual Inspection =====
+==== Leaking with engine running ====
-Degrease the bike until there's no oil remaining. \\
+  * Degrease the bike until there's no oil remaining. \\ Then take some Soft n Dri (women's antiperspirant spray), talcum powder etc. and spray it around the rocker gaskets (or other suspected leaking area). ((ReddTigger of the XLFORUM http://xlforum.net/forums/showthread.php?t=1732579&highlight=rocker+box+inserts)) \\ It will go on clear but when it gets heated will turn to a white powder. Just a light film is all it takes. \\ Whenever it starts leaking it'll show up exactly where the leak is. \\
-Then take some Soft n Dri (women's antiperspirant spray) and spray it around the rocker gaskets (or other suspected leaking area). ((ReddTigger of the XLFORUM http://xlforum.net/forums/showthread.php?t=1732579&highlight=rocker+box+inserts)) \\
+  * Clean the engine, then start it and use a bright light to see where the leak is coming from. ((Bob F of the XLFORUM http://xlforum.net/forums/showthread.php?p=5774586)) \\ The light should make the liquid oil shine. You may only have to run your scoot for a few seconds to start leak.
-It will go on clear but when it gets heated will turn to a white powder. Just a light film is all it takes. \\
-Whenever it starts leaking it'll show up exactly where the leak is. \\
 |Rocker boxes sprayed with powder antiperspirant to detected oil leaks. ((photos by CitySlicker of the XLFORUM http://xlforum.net/forums/showthread.php?t=1732579&highlight=rocker+box+inserts&page=2))||
 |{{:techtalk:evo:oil:diagnosing_oil_leak_1_by_cityslicker.jpg?direct&300|}}|{{:techtalk:evo:oil:diagnosing_oil_leak_2_by_cityslicker.jpg?direct&300|}}|
+==== Leaking with engine shut off ====
+  * Clean the area thoroughly (like with rake cleaner and air blow dry). ((Ferrous Head of the XLFORUM http://xlforum.net/forums/showthread.php?p=5774586)) \\ Let it sit long enough to begin leaking and blow some talcum powder aver the area. \\ The talc will stick to the oil and pinpoint the origin. \\
+  * Take an old bike tube and cut a piece while retaining the valve stem. ((ezmerf of the XLFORUM http://xlforum.net/forums/showthread.php?p=5774586)) \\ Use a hose clamp to tighten it over the filler neck on the oil tank. \\ Then put a lb are two of air pressure on it and see if that helps you locate where it's coming from.
+==== Leaking out the breather vent(s) ====
+  * If you've installed external breather vent hoses, make sure there are no kinks in the lines(s) that would stop or slow down the engine from breathing. \\ This would bottle up crankcase pressure and cause the internal pressure to implode the gaskets and create a leak. \\ Also make sure there are no obstructions (sludge) in any bends that may be in the lines. \\ However, a few drips of oil out a vent hose while parked is normal. \\ This does not qualify as oil 'puking' out of the vent (which is more of a sudden rush of oil).
+  * In a perfect world, you would only have a slight oil mist coming out of the crankcase breather which could easily be routed into the air cleaner. \\ (keeping the E.P.A. happy by depositing the oil back into the engine instead of dripping on the ground). \\ On 91-up Sportsters, this problem has been almost eliminated with the OEM breathers venting into the A/C. \\ But the problem still appears on 90< Sportsters and newer models with external vent lines added.
+  * The breather vents usually work fine on OEM engines. Problems have been noted however when bigger pistons / performance upgrades have been added. \\ Engine upgrades sometimes comes with extra baggage. \\ Bigger pistons brings with it more air displacement under the pistons (higher air volume in the lower case).
+  * Heavy oil flow 'puking' from the breather vent(s) only on cold start up could be from a sit-sumping condition where oil is draining into the sump when parked. \\ Your motor may be filling with oil while the bike is not running and it all gets pushed out the breather when you start the bike.
+  * Known causes for 'sit-sumping' include:
+    * Oil seeping past the oil pump check ball / check valve. Often this can be corrected by simply replacing the ball or valve in question. \\ In more severe cases the check-ball seat may need to be resurfaced.
+    * Clearances in the oil pump or gerotors out of service limit.
 ===== Internal Inspection =====
+See also in the Sportsterpedia: \\
   * [[techtalk:ref:svcproc20|Performing a Compression Test]]
   * [[techtalk:ref:svcproc21|Performing a Leak-Down Test]]
+==== Check the breather valves (umbrellas) ====
+The umbrella valves are simple rubber flaps that will get hard over heat and time. \\ They should be inspected periodically for hardness and replaced if they are not soft. \\
+  * 86-03 umbrellas are now obsolete parts. You may find some NOS ones at your local dealership or online. \\ An alternative is to install an external reed valve inline when your OEM umbrella fails.
+  * 91-03 models have the umbrellas visible with the top rocker box section removed. \\
+  * 04-up umbrellas are not replaceable themselves as they are built inside the 'replaceable' plastic breather valve assembly.
+|  86-90 cap, tube and umbrella ((photo by norseXL of the XLFORUM http://xlforum.net/forums/showthread.php?t=72099&page=25))  |  86-90 breather baffle tube installed ((photo by Bryan350 of the XLFORUM http://xlforum.net/forums/showthread.php?t=1712011))  |
+|{{:techtalk:evo:oil:86_crankcase_vent_3_by_norsexl.jpg?direct&300|}}|{{:techtalk:evo:oil:89_cam_cover_3_by_bryan350.jpg?direct&200|}}|
+|  91-03 breather valves ((photo by Hippysmack))  |  04-up breather valves ((photo by chris_b_owens of the XLFORUM http://xlforum.net/forums/showthread.php?t=1832762&page=47))  |
+|{{:techtalk:evo:oil:umbrella_valve_locations_by_hippysmack.jpg?direct&300|}}|{{:techtalk:evo:oil:2013_crankcase_breather_4_by_chris_b_owens.jpg?direct&300|}}|
+==== Check the spark plugs for oil fouling ====
-Check your spark plugs for oil fouling. \\
 {{:techtalk:evo:oil:hunting_for_oil_leaks_7_by_cjburr.jpg?direct&300|}} ((photo by cjburr of the XLFORUM http://xlforum.net/forums/showthread.php?t=53769&highlight=valve+guide&page=14)) {{:techtalk:evo:oil:hunting_for_oil_leaks_8_by_cjburr.jpg?direct&300|}} ((photo by cjburr of the XLFORUM http://xlforum.net/forums/showthread.php?t=53769&highlight=valve+guide&page=14)) \\
+==== Check intake and exhaust ports in the heads ====
 You can pull your exhaust pipes and intake manifold and look at the valves to see if the oil is leaking past the valve stem seals. ((cjburr of the XLFORUM http://xlforum.net/forums/showthread.php?t=53769&highlight=valve+guide&page=15)) \\
@@ Line 79: / Line 143: @@
 {{:techtalk:evo:oil:hunting_for_oil_leaks_9_by_cjburr.jpg?direct&200|}} ((photo by cjburr of the XLFORUM http://xlforum.net/forums/showthread.php?t=53769&highlight=valve+guide&page=16)) {{:techtalk:evo:oil:hunting_for_oil_leaks_10_by_cjburr.jpg?direct&300|}} ((photo by cjburr of the XLFORUM http://xlforum.net/forums/showthread.php?t=53769&highlight=valve+guide&page=16)) {{:techtalk:evo:oil:hunting_for_oil_leaks_11_by_cjburr.jpg?direct&300|}} ((photo by cjburr of the XLFORUM http://xlforum.net/forums/showthread.php?t=53769&highlight=valve+guide&page=16)) \\
+==== Check oil smudge marks when removing the heads ====
+When dismantling the top end (or to bring parts to your mechanic)and before cleaning the head gaskets / surfaces, check them for oil smears. ((IronMick of the XLFORUM http://xlforum.net/forums/showthread.php?t=1940586&page=2)) \\
+Smudge marks can be a give away as to where any leaks might occur. Also take a few pics of them (no flash, direct light and a steady hand). \\
+The gasket has been known to raise around the head oil drain and only on the inside edge of the gasket. \\
+So no outward sign of the leak. With the head removed an experienced eye may be able to spot the problem. \\
 \\
 [[:techtalk:menu|{{:techtalk:gototechnicalmenu.jpg|}}]]

Trace:

Differences

Navigation

Search

Toolbox