Differences

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--- techtalk:ref:oil15 [2019/06/13 00:32]
hippysmack [Expected Oil Pressure]
+++ techtalk:ref:oil15 [2022/09/27 05:34]
hippysmack [At Rocker Box (1957-1985)]
@@ Line 2: / Line 2: @@
 ====== REF: Oiling & Lubrication ======
 ====== Installing an Oil Pressure Gauge ======
+{{ :techtalk:evo:oil:oil_pressure_switch_threads_by_hippysmack.png?direct&300|}} ((drawing by Hippysmack)) \\
 The presence of oil pressure is usually measured by whether the oil light is on or not. \\
 The so called, idiot light, simply lets you know that the oil pressure is high enough to actuate the oil pressure switch and then the light. \\
@@ Line 37: / Line 39: @@
 The gauge should show some pressure even if it's not to par with the manual. \\
 Some say an oil pressure gauge makes a nice back-up to the oil light though. ((ironhead7777 of the XLFORUM http://xlforum.net/forums/showthread.php?t=263589&highlight=lower+oil+pump&page=3)) \\
-===== 86 and Up models =====
+===== 57-85 models =====
+==== Testing per the FSMs ====
+The testing point in the FSMs is at the oil pressure switch location on the oil pump. \\
+The switch is removed and the gauge is installed there. \\
+The engine is fed oil internally from the pump and the switch location is the only feed oil outlet on the pump. \\
+Installing the gauge here works since the IH pump feed simply runs by the switch location on it's way into the engine. \\
+(preventing excess pressure buildup to the gauge) \\
+{{:techtalk:ref:oil:installing_an_oil_gauge_8_by_hippysmack.jpg?direct&300|}}
+{{:techtalk:ref:oil:installing_an_oil_gauge_9_by_hippysmack.jpg?direct&300|}} \\
+==== Testing at the rocker box ====
+A Sportster does produce oil pressure in the rocker box: reportedly 3-5 psi at hot idle and 15psi+ on cold startup on an ironhead. ((simeli of the XLFORUM http://xlforum.net/forums/showthread.php?t=263589&highlight=lower+oil+pump&page=4)) \\
+Depending on the gauge selected, there may be little to no oil pressure registered on a high range gauge testing form the rocker box. \\
+(the gauge may show some pressure when the oil is cool and thick but may not show any after 5 minutes of running) ((mycle1000 of the XLFORUM http://xlforum.net/forums/showthread.php?t=263589&highlight=lower+oil+pump&page=3)) \\
+Due to the low oil pressure at the rocker box, \\
+Don't get scared when you look down after its hot and its on zero. ((vyper202 of the XLFORUM http://xlforum.net/forums/showthread.php?t=1698960)) \\
+  * Residual crankcase pressure and working pressure from the oiling tubes resides in the rocker boxes.
+    * On a cold startup, the pressure is higher due to the thicker oil present.
+    * As the engine warms up, the oil thins out and the pressure is reduced in the rocker boxes.
+    * Pulsating crankcase pressure (air and oil mist) resides over the entire breathing system as well as the rocker boxes. \\ (even though the crankcase pressure is vented through the cam cover).
+    * So, it is possible to notice different pressures with a pressure gauge testing from the rocker box.
+    * However, a gauge tapped into any rocker box will most likely measure air pressure instead of oil pressure.
+    * As air will compress and oil will not, therefore the readings should be lower than if you were testing at the oil pressure switch.
+    * Also oil ends up in the bottom of the rocker box to the head drains and air resides in the top of the box.
+===== 86 and Up models =====
 ==== Testing per the FSMs ====
 On 86-91 models, the 1/8" plug between the tappet blocks on the right case is removed and the gauge hose is installed there. \\
+These models have a pressure regulator built into the filter pad. \\
+When the regulator activates, main oil pressure in the filter pad will be lower. \\
+Testing from the tappet area will show actual working pressure to the engine without the high loss from the nearby regulator. \\
+(main pressure will still be lower until the regulator closes) \\
 However, the FSM also gives pressure readings for testing at the oil pressure switch. \\
 On 92 and Up models, the oil pressure switch is removed and the gauge hose is installed there. \\
-Oil is more restricted at the oil pressure switch at the filter pad. \\
+Oil is more restricted at the oil pressure switch location in the filter pad. \\
 So oil pressure will be higher when tested at the switch location than when tested between the tappets or in the rocker box. \\
-There also should no air inline to compress and change the pressure readings. \\
+There also should no air in the feed line to compress and change the pressure readings. \\
 Below are some general drawings on hooking up the gauge. ((drawings by Hippysmack)) \\
 {{:techtalk:ref:oil:installing_an_oil_gauge_5_by_hippysmack.jpg?direct&300|}}
-{{:techtalk:ref:oil:installing_an_oil_gauge_3_by_hippysmack.jpg?direct&300|}}{{:techtalk:ref:oil:installing_an_oil_gauge_4_by_hippysmack.jpg?direct&300|}} \\
+{{:techtalk:ref:oil:installing_an_oil_gauge_3_by_hippysmack.jpg?direct&300|}} \\
-{{:techtalk:ref:oil:installing_an_oil_gauge_5_by_hippysmack.jpg?direct&300|}}
-{{:techtalk:ref:oil:installing_an_oil_gauge_3_by_hippysmack.jpg?direct&300|}}{{:techtalk:ref:oil:installing_an_oil_gauge_4_by_hippysmack.jpg?direct&300|}} \\
+{{:techtalk:ref:oil:installing_an_oil_gauge_4_by_hippysmack.jpg?direct&300|}} {{:techtalk:ref:oil:installing_an_oil_gauge_10_by_hippysmack.jpg?direct&300|}} \\
-==== Between the oil pump and the filter ====
-Do not test straight off the oil pump feed line. \\
+==== Testing at the rocker box ====
-Oil flow will stop to the engine and the pump will build enough pressure to destroy the gauge. \\
-{{:techtalk:ref:oil:installing_an_oil_gauge_2_by_hippysmack.jpg?direct&300|}}
-{{:techtalk:ref:oil:installing_an_oil_gauge_6_by_hippysmack.jpg?direct&300|}}{{:techtalk:ref:oil:installing_an_oil_gauge_7_by_hippysmack.jpg?direct&300|}} \\
+A Sportster does produce oil pressure in the rocker box. \\
-==== Rocker Box ====
-A Sportster does produce oil pressure in the rocker box: reportedly 3-5 psi at hot idle and 15psi+ on cold startup on an ironhead. ((simeli of the XLFORUM http://xlforum.net/forums/showthread.php?t=263589&highlight=lower+oil+pump&page=4)) \\
 Depending on the gauge selected, there may be little to no oil pressure registered on a high range gauge testing form the rocker box. \\
 (the gauge may show some pressure when the oil is cool and thick but may not show any after 5 minutes of running) ((mycle1000 of the XLFORUM http://xlforum.net/forums/showthread.php?t=263589&highlight=lower+oil+pump&page=3)) \\
 Due to the low oil pressure at the rocker box, \\
 Don't get scared when you look down after its hot and its on zero. ((vyper202 of the XLFORUM http://xlforum.net/forums/showthread.php?t=1698960)) \\
   * Residual crankcase pressure and working pressure from the lifters resides in the rocker boxes.
     * On a cold startup, the pressure is higher due to the thicker oil present.
     * As the engine warms up, the oil thins out and the pressure is reduced in the rocker boxes.
-    * Excess crankcase pressure (air and oil mist) is vented differently between pre and post 91 engines.
+    * Pulsating crankcase pressure (air and oil mist) is vented differently between pre and post 91 engines.
       * On pre 91 engines, excess crankcase pressure is vented through the cam cover.
       * On post 91 engines, excess crankcase pressure is routed up the pushrod tubes and vented thru the rocker boxes to exit a hole in each head.
@@ Line 81: / Line 106: @@
     * However, a gauge tapped into any rocker box will most likely measure air pressure instead of oil pressure.
     * As air will compress and oil will not, therefore the readings should be lower than if you were testing at the oil pressure switch.
+    * Also oil ends up in the bottom of the rocker box to the head drains and air resides in the top of the box. \\
+==== Testing between the oil pump and the filter ====
+and prior engines use an oil filter in the return side of the system after the oil exits the engine. \\
+So an oil pressure gauge between the pump and filter would not tell you much about the engine feed oil. \\
+In 1986, the oil pressure switch was moved to an external feed side oil filter. \\
+Future feed oil from Evo oil pumps comes out of the pump to the filter pad. \\
+Consequently it's not possible to block the pump outlet with a pressure gauge without starving the engine of oil. \\
+So installing a gauge on the oil pump fittings is not going to be very helpful. \\
+Also, installing a pressure gauge straight into a gauge will result in the pump building up enough pressure to destroy the gauge. \\
+However, it is possible to install gauge in the feed line from the pump to the filter pad using a tee fitting. \\
+That way, as the pressure builds, it will both enter the gauge and the flow into the engine. \\
+{{:techtalk:ref:oil:installing_an_oil_gauge_2_by_hippysmack.jpg?direct&300|}}
+{{:techtalk:ref:oil:installing_an_oil_gauge_6_by_hippysmack.jpg?direct&300|}}{{:techtalk:ref:oil:installing_an_oil_gauge_7_by_hippysmack.jpg?direct&300|}} \\
@@ Line 144: / Line 185: @@
 {{:techtalk:evo:oil:98_cam_chest_by_hippysmack.jpg?direct&300|}} ((photo by Hippysmack))
+===== At the Oil Pump =====
+|Parts. ((photo by rocketmangb of the XLFORUM http://xlforum.net/forums/showthread.php?t=2049680))|
+|{{:techtalk:ref:oil:oil_pressure_gauge_rig_2_by_rocketmangb.jpg?direct&300|}}|
+|Hoses lengths. ((photo by rocketmangb of the XLFORUM http://xlforum.net/forums/showthread.php?t=2049680&page=2))|Hook one end to the filter pad. ((photo by rocketmangb of the XLFORUM http://xlforum.net/forums/showthread.php?t=2049680&page=2))|Hook the other end to the oil pump. ((photo by rocketmangb of the XLFORUM http://xlforum.net/forums/showthread.php?t=2049680&page=2))|
+|{{:techtalk:ref:oil:oil_pressure_gauge_rig_3_by_rocketmangb.jpg?direct&300|}}|{{:techtalk:ref:oil:oil_pressure_gauge_rig_10_by_rocketmangb.jpg?direct&300|}}|{{:techtalk:ref:oil:oil_pressure_gauge_rig_4_by_rocketmangb.jpg?direct&300|}}|
+|Hold or mount the gauge where you want it. ((photos by rocketmangb of the XLFORUM http://xlforum.net/forums/showthread.php?t=2049680&page=2))|||
+|{{:techtalk:ref:oil:oil_pressure_gauge_rig_5_by_rocketmangb.jpg?direct&300|}}|{{:techtalk:ref:oil:oil_pressure_gauge_rig_6_by_rocketmangb.jpg?direct&300|}}|{{:techtalk:ref:oil:oil_pressure_gauge_rig_9_by_rocketmangb.jpg?direct&300|}}|
 ====== IH ======

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