Boxerworks.com

New member and i have a question.
In the process of refurbishing a 1975 R90S.
Once I removed the transmission from the block it was apparent that either the rear main seal or oil pump cover gasket was leaking based upon the amount of built up gunk in the flywheel/clutch cavity.
After blocking the crankshaft I removed the clutch parts followed by the flywheel. Once the flywheel was removed I notice that the rear thrust washer was not captured on its pins. It was possible to rotate it in the area between its pins and the rear seal. I reinstalled it on its pins but I am concerned as to whether or not the fact that it could come off its pins is customary or if I might have an issue.
Can anyone advise me on this scenario?
Thanks for any advise.
Patrick

Gidday, is there evidence of the thrust washer spinning during engine operation? That would be seen as a trench running around the washer at the pin radius.
The pins may have been pushed 'into' the engine case. The inner thrust washer is held on the same pins as the outer.
If the outer thrust washer was not on its pins and the flywheel was torqued, it would drive the pins in.
The pins should be just under the thickness of the thrust washer.

Looking at the fact that you've been able to relocate the thrust bearing on it's pins and assuming there is no evidence, as ME109 mentions, that the locating pins have been pushed into block, I would be fairly sure that the bearing simply pulled off the pins as you removed the flywheel. This isn't uncommon and happens because the oil forms a vacuum effectively sticking the bearing to the flywheel. The same adhesion occurs between the bearing and the block and it is a toss up which one wins the tug of war as the flywheel is removed.

In principle, unless the pins have moved or the flywheel has been very loose, it simply isn't possible for the bearing to move until the flywheel is removed.

I would be quite happy, all other things being equal, to reassemble the flywheel to the engine. The only precaution I'd take is to first lightly crimp up the flywheel bolts then remove whatever you used to block the crank then, as the bolts are torqued up, check that the engine rotates freely. Any sign of binding, stop immediately and investigate further... this is a good precaution in any case.

Rob

Thanks for the replies.
After reassembling per advise received I'm pretty certain all is well.
Crank spun freely throughout process.

Pfix wrote: ↑Sun Dec 22, 2019 5:04 am
Crank spun freely throughout process.

Blocking the crank will do that for you, well done.