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Old 02-10-2012, 07:46 PM
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Originally Posted by Augusto
cooling system has nothing to do with this problem

the symptoms lead to a clogged exhaust or a clogged carburator

also a bad fuel pump can do the same

if there are no backfires or the engine keeps running after the ignition is cut, I would say the ignition sustem is fine, but I'll look anyway under the distribuitor rotor for a frozen timing advance mechanism.

does it smoke black when the problem happens? this will lead you to an overly rich clue, like a choke plate that shuts or a bad needle valve.
I've always wondered about the fuel pump. Any way to test it? It is a mechanical. Over a year ago, the truck began having problems after someone dumped water and debris into the gas tank. I eventual had to rebuild the carb. I imagine the junk may have caused some damage to the fuel pump.

I can't imagine what could possible be clogging the exhaust, especially since the problem appears to clear up after a few minutes of idling and revving the engine several times.

There have been no back fires, but the engine does not keep running after the ignition is cut (I hope I understood that correctly).

Aside from a bit of white smoke after starting (condensation?), there is no smoke that I've noticed. I will pay attention to that next time.
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