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Old 09-26-2017, 10:22 PM   #1
NeverDone50
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Join Date: Aug 2014
Location: Overland Park, Kansas
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Engine trouble 292

So I have a 292 swapped into my '50 and I'm having some issues. When starting up, it spits back/coughs through the carb (rochester 1bbl). So i've rebuilt the carb, it's been timed 4 degrees BTC, new pertronox kit, new spark plugs, etc. Anyway, I can get it started, but I it wont run unless I set the idle around 1000 rpm. If I try to tune the idle lower, it coughs randomly and dies. So I did a compression check and all the cylinders were reading about 125-130psi except cylinder 1, which was reading 90 psi. I poured some oil in the cylinder and rechecked the compression and it didn't change. I'm assuming its a leaky intake valve. I'm not a mechanic and I'm learning as I go so what are my options on fixing this issue?
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Old 09-27-2017, 06:02 PM   #2
casper71
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Re: Engine trouble 292

Sounds like it may be an intake gasket leak. This is common when they get changed. If compression is good, valves are good. You can start truck and spray carb cleaner or brake cleaner around carb and intake. You will get smoke out exhaust and rpm increase if you find leak. Others may have better ideas, this is what I have done.
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Old 09-27-2017, 07:04 PM   #3
dwcsr
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Re: Engine trouble 292

I have to agree on the manifold. There is a procedure for replacing the gaskets, remove the manifold, remove the bolts that hold the top and bottom together. use the new square gasket that comes with the set. snug up the bolts to the top and bottom, these parts needs to move in the next step, then mount the manifold with new gaskets. tighten the bolts snugly and then torque the top and bottom half's and then torque the manifold to head bolts.

Over time they move to conform with the old gasket and you have to level it out if you change to a new one.
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Old 09-28-2017, 05:01 PM   #4
NeverDone50
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Re: Engine trouble 292

That does make sense. I haven't changed the gasket (although I should have) but the chain for the engine hoist was bolted to the manifold. So I probably didn't torque it proper back down. Thanks for the insight. I've been getting frustrated with all the little things keeping me from driving it.
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Old 09-28-2017, 10:52 PM   #5
tmoble
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Re: Engine trouble 292

It's always something. but the issues usually get smaller as you go along. Nice when guys like dwcsr help out with their massive experience.
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