idle?

barbee6043 said

76 Volare roadrunner 318, bbd carter 2 bbl, auto stock everything I figure Mileage reads 95,000, I guess 195,000. Have no idea it has ever been apart.
I can not get a constant idle anymore. Warmed up, ran great till recently. I did put a new fuel pump and filter on it. Warmed up, if I put it in gear the rpm drops from 8-900 to 400 and wants to die, Driving down the road, I slow down and it dies.
After warmed up, I noticed I can close the choke butterfly a little and the idle speeds way up. I cannot find any vacuum leaks, just a very slight one at the throttle shaft. I sprayed carb cleaner in the PCV valve.

I had a 318 once that the timing chain was plenty loose and would die at a stop sign. Timing would get out.
Is this a carb issue or what??

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If you don't have any vacuum leaks then the fact that you close the choke a little and it speeds up points to junk in the idle circuit.
Here's what I do very first thing when I run across this scenario.

Turn your idle screws in all the way counting the turns it takes to bottom them out lightly.
Pull both screws and shoot each hole with a healthy shot of WD, PB Blaster or whatever you have laying around. (what it is does not really matter)
Then hit each hole with a good shot of compressed air.

Put your idle screws back in and bottom them out lightly again, the count the turns backing them out until you are at about the same turns they were.

This does it pretty much every time.

When you change pumps or even filters there is almost always something that breaks loose and ends up in the bottom of the float bowl/s and gets into the idle circuits.
The fluid sprayed in them before the air shot helps to carry the junk out of them.

This is easy to do and like I said, it works really well.