Super M rough runner

Anonymous-0 · Jun 27, 2012

1953 Super M is running rough after heating up. popping alot. Bluish smoke. I just recently tuned it all up, cleaned carb and bowl, adjusted carb at idle, valve job, new ignition parts, plugs, oil Everything I can think of. When it is cold, starts and runs really smooth without a pop ever. As it heats up and especially under load, it starts to really run ratty and loose oil pressure. Cold manifold with alot of condensation too.

Andrew Z · Jun 27, 2012

Compression test sounds like the next step

Andrew

The Red · Jun 27, 2012

check your spark. The coil might be breaking down when it gets hot.

old · Jun 27, 2012

Cold manifold it correct since it is part of how a carb works. As for ruffing running when hot most of the time that is a coil going south or valves that are getting to tight. Check the spark when it starts doing that. Should be a blue/white spark that will jump a 1/4 inch gap or more

Dalrymple · Jun 27, 2012

Cold manifold with a lot of condensation may mean carb ice. Shut it down for just a couple of minutes then restart. If it's smooth for a few more minutes, probably ice?

GordoSD · Jun 27, 2012

My experience is that coils go south and then they are bad from cold to warm to hot. Condensors on the other hand will work perfectly cold and then not at all when hot. 2 stroke racing motorcycles are notorious for this problem. BTDT.

Brownie 450 · Jun 28, 2012

Sounds like a valve too tight.

Super M rough runner

Anonymous-0

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Andrew Z

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The Red

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old

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Dalrymple

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GordoSD

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Brownie 450

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