47 cub

whig · Apr 9, 2012

Number 1 and 2 cylinder plugs get oil fould after about an hour of running. ,blue smoke from exhaust. Do you think it is rings, valve guides or maybe both? Oil pressure is between 30 and 40 and runs great until it starts to skip from oil fouled plug.Did thye use valve guide seals back then? Thanks for any help. Wayne

Denny ('60 Lo-Boy) · Apr 9, 2012

Do both a dry and wet compression check. Do the dry first and note the compression readings. Then put a little oil in the cylinders and do it again. If the reading rises the rings are worn, if not then the valves are leaking.

John M · Apr 9, 2012

Id guess the rings, since the valves arent in the head. Not syying that isnt the problem, but theres no valves in that head.

El Toro · Apr 10, 2012

You probably need to rebuild the engine. Have the cylinders measured for wear. They may need to be bored oversize. Have the crankshaft measured too. Buy your bearings from them. Have the shop to do a valve job. I would install new valve springs. Hal

Matt Tieken · Apr 10, 2012

As a bandaid, I have used anti-fouling adapters and they worked great. The plugs will still foul, but it will take longer.

47 cub

whig

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Denny ('60 Lo-Boy)

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John M

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El Toro

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Matt Tieken

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