Weird Oil Leak

[James Rogers]

Originally Posted by Purdy Swoft

The oil pump pumps the oil up into the valve chamber where it flows to the mainand cam bearings by gravity. When the engine is shut off oil remains in the valve chamber untill it can slowly flow to the bearings. There is a slinger that is part of the crankshaft and rides inside the rear main bearing . When the car is parked with the front end uphill the oil in the valve chamber continues to flow by gravity untill the chamber drains and can and will flow right past the oil slinger on the rear of the crank shaft When this happens the oil collects in the flywheel housing and drips out the hole in the bottom of the housind with the cotter pin. Also, if it leaks less with the oil filler cap removed, this indicates that the oil cap is restricting breathing inside the crankcase and allowing poressure to build up. There can be other problems but I will leave that for others.

Actually Purdy, you are correct in all you post except one thing. The oil will flow past the slinger and collect in the front of the flywheel and scare the daylights out of you if you don't know this. It will soon stop if the bearings are in spec and the flywheel empties.