Sorta OT - V8 carb Q, On topic for the V8 teener guys Options

[Gint]

It's been a looong time since I had a good old fashioned 'murican carb'd V8. My 72 Chvy truck has had an ongoing hot start issue. After running it to full temp and shutting it off and coming back to start after 10 minutes or longer (until it cools off anyway, then everything is fine), you have to open the throttle at least half way to get it to start. And then it runs like crap for a few minutes. Then all is well again. I've suspected fuel boiling for a while now, so I rebuilt the Edelbrock 600 carb today to verify float settings and general health of the carb.

Today after I finished it and drove it and warmed it up, I waited 10 minutes and then tried to restart. The problem still exists. I pulled the air cleaner off and I could hear fuel bubbling. There was fuel leaking from the secondary throttle shaft on the right side of the carb as well. Taking the carb top off revealed fuel in the right side bowl still bubbling a tiny bit. The float bowl is dumping fuel into the secondary cavity and causing the leak at the secondary throttle shaft and dumping fuel into the manifold. So root cause is determined. I have a buddy that is going to give me a phenolic spacer and gasket that I will install later this week.

Is this fairly typical?

[andys]

Gint,

I'm assuming intake and exhaust manifolds are stock. Check first to see if your heat riser valve is stuck closed, as they often can in an older vehicle. If stuck closed (or partially closed), it will send exhaust gasses through the intake manifold under the carb, and heat it up real good. A phenolic spacer might cure the symptom in this case, but not the cause. Might also check the EGR valve to see if it perhaps isn't stuck open, as well as a closed thermal valve in the air cleaner horn. If fuel is boiling in the carb, I'd look for a heat source.

Andy