I have a 1980 Corvette that I have been working on a bit. I just finished rebuilding the Rochester Quadrajet and have tried setting the jets at 2 turns, 3 turns and 4 turns. In each case I can start the engine but it takes a lot of pumping the gas, runs very rough once started, and cannot hold an idle. Also when I am firing it up the carb has belched flames. I know I need to check vacuum but need to get it to be able to idle first. Any thoughts on this would really be appreciated. I have read many of the old posts that relate to this but still can't seem to resolve.

 

I would also check the timing, is the choke working correctly? If your vacuum system is solid you may need to check the timing chain.

 

Thanks Harley; I will check the timing after I double check the vacuum.

 

Here is an easy way to check your timing chain.
pull plugs. Pull the distributor cap. Put a breaker bar on the crankshaft. Roll engine to top dead center. (Either direction is ok, need to move at least 1/4 turn)
Now watch the rotor and turn engine the opposite direction. Stop as soon as the rotor moves!
Read the number of degrees the crank moved.
If you moved the crank 8degrees or more the timing chain needs to be replaced.

 

Wow; thanks for this.

 

JakStat: Welcome to the forum.

By any chance was the distributor pulled and replaced? You can check by putting the engine on TDC for #1 on the compression stroke (both valves closed) and remove the dist. cap. The rotor should be pointing to #1 plug. You can do this in connection w/ 74HARLEY's suggestion.

 

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