My type 4 engine is leaking oil via the threads of the flywheel bolts. How does this leak-path get sealed?

your problem is behind the fly wheel or in front of it how ever you see it! just guess n but id say rear main seal....good luck

There is an O-ring in the flywheel where it mates to the crank, it's missing or damaged.

Many don't realize that for a T4 RMS repair there's 2 seals, the RMS and the flywheel O-ring.

This is a T1 flywheel but the O-ring is installed the same way.

I didn't! I don't see how that stops oil if it mates direct to the crank.... almost seems more like a harmonic dampner ..ill be in one soon and ive got more reading to do

The RMS is under direct pressure from the #1 main bearing, the slightest scratch in the flywheel or crank mating surfaces will act like an oil galley.

One of the reasons not to use too much sealant on case halves is so you won't clog the RMS/rear main bearing oil drain notch. Clog that relief notch and the best seal in the world won't stop the oil coming out of the RMS.

you learn something new everyday but that O ring has nothing to do with keeping the oil in the motor ...maybe I`m just missing it surprise
...ill have to dig into the book more

RMS seals around the neck of the flywheel, not on the crankshaft itself.
The O-ring inside the flywheel seals it to the crankshaft.

Remove your flywheel O-ring and report your findings...they should be easy to spot on your garage floor.



Exactly.

Just in case your argument is a /6 engine doesn't have a O-ring, it has a main bearing thrust surface that acts as a slinger, much like in a VW T1 crank on the pulley end. The oil gets slung off into the case before it gets to the RMS.

This is a common mistake that I've seen since I started wenching on these in the 80's, really I've known about this since watching my brother wrench on them in the 70's.

copy copy no argument here! like I said I've got some reading to do, no better place to come when I get stumped then here though... I know that much
Thanks