Hello everyone. I'm new here and am having issues with my truck. It is a 1990 chevy 1500 with a 305 out of a 1984 (i think monte carlo but i'm not positive). I've found multiple issues..

First, the heads needed rebuilt. I found a small piece of aluminum (piece of carb?) stuck on one of the exhaust valves which kept it open 1/16". Heads are good now.

Second, the timing chain and gears where extremely worn, i replaced them and set the timing.

First of all, the guy who did my heads said it looked like it was running pretty rich. I did a minor rebuild on the quadrajet but when it warms up and i drive about 10 miles it starts cutting out and gets worse. I'm thinking the carb is junk but thought maybe the distributor is worn out. I do have a clear inline fuel filter and it is not starving for gas.

All comments or ideas would be appreciated, thanks.

 

Update, i took truck for a longer ride and found a poo..poo.....poo.poo..poo noise from the exhaust. What could cause this?

 

Looks like i'm on my own, thanks anyway.

 

If it's running rich, you aren't getting enough air to the combustion chamber. It could be something as simple as a dirty air filter. Do you have an aftermarket breather on it? The noise you hear could be that the timing is not advancing properly. Does this distributor have a vacuum operated timing advance on it? If so, it may be worn out or have a hole in the diaphragm. If you find it's okay, maybe it's not hooked up to a good vacuum source. It doesn't need to be connected to a ported vacuum switch. It needs to be hooked up to a straight vacuum connection at the base of your carburetor. Have you checked for vacuum leaks and are you sure you've got the timing right on it?

 

Could worn springs on the distributor weights be suspect? I have a feeling distributor is worn out...it just doesn't feel or sound like a carb issue. Oh, and the fuel pump is new.

 

Yep, if the springs are worn out, your timing will be off. You may still be able to find a rebuild kit for it at a local parts store. IIRC, they'll even have new weights in it.

 

Thanks Chuzz, i'll look into that.

Like i stated in first post....it gets worse the more i drive it. So i checked the ignition coil after a mile test drive and found it so hot i couldn't touch it for more than a half second and i had nitrile gloves on. Not normal, is it? Last summer my ignition coil literally melted down, the distributor was smoking and the coil was a blob. It sounds like it might be an overheating coil again.

 

Replaced the distributor with a new one but used the old coil and had the cutting in and out problem still. I installed new ignition coil and it seems like the problem is finally gone! But...i still think carb needs replaced since i can smell strong odor of fuel when it is running, yes i made sure there are no fuel leaks.

 

Set a corner stone baseline.Compression check should show all cylinders are 10% of each other.Given the damage found earlier I do think that is a important step.

Fuel pressure check should show fuel pressure no more than 3 to 5lbs for a carb.If your using the in tank pump for a TBI-that pressure without a regulator would be too much.

Electric chokes should open the choke after reaching operating temp.Take off the air cleaner and watch the choke open or not.If not then there is a circuit issue or the choke heater coil is broken.

From a TBI engine to a Carb shouldn't matter in terms of the dizzy as far as the engine is concerned.But how it plugs into the trucks wire harness is a open question I am not sure of in this swap.I would assume you when with a HEI dizzy for the carb engine.That I am 85% sure you have to do to have it work correctly.

 

I replied earlier but do not see it sooo...