Differences

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--- techtalk:ref:oil10 [2024/01/28 03:21]
hippysmack [Sit Sumpimg]
+++ techtalk:ref:oil10 [2024/01/28 16:59] (current)
hippysmack [Sit Sumpimg]
@@ Line 168: / Line 168: @@
 The most notable symptom of sit sumping is a loss of oil in the oil tank after the bike sits for a while. \\
 This is where some make the mistake of adding oil to a cold oil tank to get the level between the hashes on the stick. \\
 Adding oil to a cold motor is never a good idea. [[techtalk:ref:oil01|Click Here]] for the checking/adding oil page in the Sportsterpedia. \\
+There isn't much oil pressure on the feed side of the oil check with the motor not running. \\
+For example using Mobile 1 V-twin 20w50, app head pressure at the oil pump was calculated to be just less than 1/4 PSI on a 98 1200S. \\
+This figure will change slightly depending on your current altitude above sea level, oil density and height of oil in the tank. But just for argument sake.. \\
+And subtracting say 60-70% of that going back up to the oil filter pad leaves very little pressure against the oil check. \\
+[[techtalk:ref:oil21#oil_tank_head_pressure|Click Here]] to read more on calculating oil tank head pressure in the Sportsterpedia. \\
+The OEM spring behind the check ball keeps pressure at 4-6 PSI against the ball to it's seat according to the manuals. \\
+And doing the math, there should be less pressure on the incoming side of the check ball than spring seat pressure. \\
+Meaning there shouldn't be enough gravity oil pressure when shut down to overcome the check system. \\
+However, we know oil will leak down into the motor during shut down and for reasons below or more. \\
 When you start the engine, the excess oil in the crankcase can end up being fired out the breather(s), onto the floor, (or into your air-filter on 79-up models). \\
+It doesn't take long for the pump to return the excess oil (drained into the motor) back to the tank, then the oil level is higher there. \\
 **Known causes of sit sumping during engine down time**: \\
@@ Line 177: / Line 188: @@
     * Clearances in the pump can widen over time and allow oil to seep into the motor from the oil tank.
     * Worn / damaged seals (or plates respectively). Gravity pressure is always present on the feed side of the pump. \\ If the seals are compromised, that gravity oil will seep past the gears/gerotors respectively and into the engine.
-  * **Check Ball / Check Valve**: \\ All Sportsters have some sort of an oil check system in place. \\ The check ball can be thought of as the on / off valve for oil supply into the engine. \\ On 57-85 engines, the check is in the oil pump and on 86-up engines, the check is in the oil filter pad. \\ The main objective of the oil check is to keep the oil in the tank from entering the motor (and prevent a sit sumped condition). \\ Occasionally the check gets weak or damaged and allows oil to bypass it during shut down. \\ Some oil transfers silently from the tank into the motor.
+  * **Check Ball / Check Valve**: \\ All Sportsters have some sort of an oil check system in place. \\ The check ball can be thought of as the on / off valve for oil supply into the engine. \\ On 57-85 engines, the check is in the oil pump and on 86-up engines, the check is in the oil filter pad. \\ The main objective of the oil check is to keep the oil in the tank from entering the motor during shutdown (and prevent a sit sumped condition). \\ Occasionally the check gets weak or damaged and allows oil to bypass it or dirt/debris blocks a good seat. \\ Some oil transfers silently from the tank into the motor.
-    * The 57-76 check ball seat in the oil pump body can get dirty and / or pitted from usage and debris.
+    * The 57-76 steel check ball seat in the oil pump body can get dirty and / or pitted from usage and debris.
-    * The spring (whether check ball or valve) can break or weaken which won't push the unit against the seat properly. \\ Without adequate seat pressure, oil will bypass into the engine.
+    * The 86-E87 spring (whether check ball or valve) can break or weaken which won't push the unit against the seat properly. \\ The check cartridge can get clogged with debris and the check ball can develop a ring around the seat that may allow oil to seep past it. \\ Without adequate seat pressure, oil will bypass into the engine.
   * **Breather Gear (57-76 engines):**
     * 57-76 engines can sit sump by way of oil in the gearcase dripping into the crankcase through the window in the breather gear. \\ If oil gets into the crankcase high enough to reach the transfer valve, it'll spill over into the primary compartment. \\ Read more about the [[techtalk:ih:oil01#transfer_valve_76_and_earlier|Transfer Valve]] in the Sportsterpedia. \\
-  * **Oil Filter Adapter (1986-up engines):**
+  * **Oil Filter Adapter (1986-up engines):** The filter adapter is a 2-way threaded union installed into the filter pad.
-    * The filter adapter is a 2-way threaded union. \\ The threads on the end that connects to the filter housing (toward the motor) can leak oil past them into the motor, bypassing the check valve. \\
+    * Leaking filter adapter threads.  ((RDHenley of the XLFORUM)) \\ The threads on the end, that connect to the filter housing (toward the motor), can seep oil into the motor. \\ The adapter should have Loctite applied to the threads (end that threads into the filter pad) when installed. \\ The Loctite acts to help keep the adapter from coming loose from vibration as well as to help seal the area between the threads from seeping oil. \\ If oil migrates between the adapter to housing threads, it can bypass (get behind) the check valve / check ball and into the motor.
+    * Loose filter adapter. ((RDHenley of the XLFORUM)) \\ The hex nut in the middle of the adapter should be installed tight against the housing and torque'd to factory spec BEFORE installing the filter. \\ When removing the filter, the adapter CAN back out a few threads. \\ (especially if Loctite was either not added when it was last installed or the Loctite came loose somewhat) \\ In that instance when installing a new filter, the threaded adapter may not tighten back before the thick rubber seal on the filter mates to the filter pad. \\ The filter will still tighten up as required with no external leaks, but the adapter may be a few threads shy of being tight into the housing. \\ This would not compress the spring behind the check ball as much, thus resulting in less pressure pushing the ball against it's adapter seat. \\ And it could allow oil to push against the ball enough to allow oil to pass into the motor. \\ Or it could allow the spring to lean the ball in a position off of the ring seat indention.
 The check valve is spring loaded. Debris can lodge in the spring seat and keep it open. \\
@@ Line 190: / Line 202: @@
 |77-E87 check valve ((photo by Hippysmack))|Check valve in 77-85 oil pump ((photo by Hippysmack))|Check valve in 86-E87 filter pad ((photo by Hippysmack))|
 |{{:techtalk:evo:oil:77-e87_oil_check_valve_1_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ih:oil:77-85_oil_pump_check_valve_installed_by_hippysmack.jpg?direct&300|}}|{{:techtalk:evo:oil:86-e87_oil_check_valve_location_2_by_hippysmack.jpg?direct&300|}}|
+\\
 Even the Teflon ball had a design flaw. The ball can have a variance in landing on the seat position depending on forces to and fro. ((Hippysmack of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/88089-where-to-get-teflon-ball-for-oil-pump/page2?t=699023&page=2)) \\
@@ Line 202: / Line 215: @@
 |  L87-90 Check Ball ((photos by Hippysmack))  ||  92-up Check Ball ((photo by jordan1200 of the XLFORUM, labeled by Hippysmack https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/196304-oil-filter-mount-and-check-valve?t=2072806))  |
 |{{:techtalk:evo:oil:l87-90_check_ball_and_spring_1_by_hippysmack.jpg?direct&300|}}|{{:techtalk:evo:oil:l87-90_check_ball_and_spring_5_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:oil:92-up_check_ball_and_spring_by_jordan1200_labeled_by_hippysmack.jpg?direct&300|}}|
+\\
+The 92-up Teflon ball does have a "tail" installed into the spring, but that didn't entirely fix the problem. \\
+The longer the ball sits against the adapter, a ring indention can get impressed into the ball where it seats. \\
+The indention on the ball is totally dependent on the angle at which the individual spring rests on a regular basis. \\
+So that ring may be different on another bike depending on how long the ball has been installed and exactly how the individual spring lays at rest. \\
+Used long enough, the indention can "mushroom, per say around the ball. \\
+In that case, the ball SHOULD rest back inside that mushroomed area (which may or may not leak, depending). \\
+But that also may result in the ball getting pushed further toward the filter adapter, lessening spring pressure on the ball. \\
+And the more it mushrooms, the less back tension you'll get from the spring. \\
+Low tension from the spring can result in oil seeping past the ball.
+\\
+This one on a 2005 Sportster has the ring indention but it has not mushroomed and does seal. \\
+{{:techtalk:ref:oil:2005_sportster_oil_pump_check_ball_-_ring_indention_by_rdhenley.jpg?direct&400|}} ((photo by RDHenley of the XLFORUM)) \\
+\\

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