oil window

1 reply to this topic
  • delmas

Posted March 14, 2010 - 06:25 AM


what is and should it always spin,
the circle tab in the oil window

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  • grayracer513

Posted March 14, 2010 - 08:31 AM


I haven't looked at this much yet, but the oil window is placed very near to the point at which the oil returning from the sump is delivered back to the internal oil "tank". If the circle tab you mention is designed to spin as a result of oil flowing over it, then no, it would not and should not spin constantly.

In a dry sump oiling system, there are two oil pumps; feed and return. The feed pump lubes the engine, while the return picks up the used oil from the bottom of the engine and sends it back to the tank. The return pump is deliberately made to have a higher volume than the feed so that it can always stay ahead of the oil draining to the sump, so that the maximum available amount of oil will always be in the tank, ready to feed the engine. Since it moves oil faster than the feed does, the return pump ends up picking up a lot of air, so an unsteady, interrupted return oil flow is normal. If the tab you speak of is designed to spin as oil flows over it, I would expect it not to turn constantly for a very long period once the engine is warmed up a little.

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