Topic: Hard Start
in Forum: C3 Engines
My 78 is hard to start after it sits over night. I must pump the accelerator several times and turn it over more than I think is normal to start it. Once starts, it runs and idles well. It will start immediately after sitting for 4-5 hours with no problems. Two things I have noticed that could be related.
> It will sometimes blow out a puff of blue smoke once it starts after sitting overnight. It doesn’t do it every time.
> I replaced the spark plugs shortly after I got the car back in January. All the plugs looked OK except #1 and #6. Both these plugs had slight signs of oil fowling.
I am suspecting that the primary culprit is bad valve stem seals. But, I am also suspicious about the intake manifold gasket. I have checked it for vacuum leaks a few times and haven’t found any.
Do I need to check anything else or should I just replace the valve stem seals first?
Doing the seals will normally stop that pesky puff of smoke...
IMHO...
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The paper type filter should have a rubber check-valve in the inlet side. Sometimes, people will remove the valve so it doesn't restrict fuel flow. A downside is the fuel will drainback/siphon out of the carb when the engine is shut off.
Also, just because the cab was rebuilt doesn't mean it can't still leak internally. It sound like the welch plugs on the bottom of the fuel bowl are leaking overnite, and creating a long crank time. It's a fairly easy fix if that if the problem.
Check out Ken's carb article for an excellent tutorial on Q-jets.(click on the
button, then the "QuadraJet" button. 
)Joel Adams
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when you pump the accelerator, does it squirt fuel into the intake when the engine is cold?
With the engine off. I can pump the accelerator about 4 times with squirts each time but after that, it stops squirting. The carb already has epoxy at all the common leak points.