8BA Rear Seal Replacement

[Highboy34]

When installing the 8BA rear seal, is the pan gasket left long and compressed between the upper and lower seal retainers and seals, or is it trimmed to meet the retainers? I've read different opinions and would appreciate current thinking.

Thanks to all.

[Step-down]

My rope seal came with a shim to cut the rope long

[Frank Miller]

Highboy asked a good question. The rope seal or graphite impregnated seal that came with mine had a knife and gauge to trim it to the thickness of the pan gasket. The pan gasket has two tabs that run up to the crank and it makes sense to want to trim them to the graphite seal. I did not because I was told not ot. No major leaks but I often think I did it wrong. It makes more sense to have the seal ends meet and not compress on the gasket. I think it was a best gasket kit and the instructions should have explained this but they do not.

[Highboy34]

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Step-Down and Frank,

Appreciate your comments. I also called several friends including one who's an experienced engine builder of both stock and blower flatheads, many 8BA's. The consensus was to leave the Best Gaskets pan gasket its out-of-the-box length, sandwiching the gasket between the upper and lower seal retainers with RTV dabbed on both sides. And thinking about it, that makes sense. If Best Gasket intended their gasket to stop at the edge of the retainer, why would they add the extra length to it, intending that the assembler then trim it? And the length of their gasket, from the closest pan bolt hole to its end is exactly to the inside of the retainer, not the outside.

Anyway, it'll get assembled this way today. I'll let you know how it works.

Many thanks,

Steve