The crankshaft oil seal on my bro's bus keeps blowing, we're not sure why. The engine, a '74 tp, is in good condition, no blow by, breather pipe is clear and pressure relief valve moves freely. After 3 years of perfect running it's blown 3 in as many months! We've tried black German seals, red Mexican, and now a red German seal (which looks the best of the lot). We've seated the seal all the way back and also flush with case...someone suggested the crankshsft maybe worn oval? Any ideas are welcome now! It's leaking from the inner flywheel bit.
TIA
--Steve
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