I have lately been wondeing about those rear main seals.
There is the earlier rope seal and the angled knurling on the crank seal area. I can see how this works with the engine running winding the oil back into the engine with the knurling. With the engine sitting off, can the oil seep back through the knurling?
Then on a rebuild or newer lip seal rear main seal. The new lip seal sitting on the knurling, with it running pushes the oil back into the engine.
With the engine stopped the new lip seal would be bridging the knurling peaks and allowing oil to run back out throgh the knurling valleys ??
So my question is with the lip seal style rear main seal, would it be a good idea to polish down the knurling smooth so the rear main lip seal has a smooth surface for the lip to seal against.
Just like the smooth surface seal up on the front harmonic balancer and timing cover.
Also wondering if the aftermarket cranks and stroker cranks have eliminated the knurling altogether ???
Maybe even the stock reman cranks have the knurling removed as part if their reman process ??
Granted you want a good vented crank case and PCV setup to eliminate any positive crank case pressure pushing the oil out.
Any thoughts or opinions on this ???
