Hi everyone, I just bought a '76 Sedan Deville in "good" condition for a very fair price. It will need some cosmetic work but I want to get this fixed first. Now the engine just rolled over to 80,000 miles and when its hot, it starts perfectly. Now when its cold, I really have to pump it a lot and then keep my foot on the gas till it warms up. My 425 only takes a MAX of 3 pumps, but if I don't pump this at least 8 times it just cranks. So I pump it and the cranking gets faster and faster and finally catches then it will die if I don't give it any gas, yet I can't give it too much or it will die too! So I have to just barely touch the pedal to keep it running till its warm. I looked at the choke first and it seems to be functioning, any other suggestions?? Idle Screw maybe??

Thanks

With either engine, there should not be a need for any pumping of the accelerator. I simple push to the floor to engage the choke is all that should be needed.

By the way, what is the ambient temperature when you are starting the engine cold?

Is the choke plate fully closed when the engine is cold?

Is the a factory Quadrajet and not an aftermarket carburetor? If so, choke setting should be 2 notches RICH. Check the float level, it should be 13/32" or 7/16" depending on the carb number. If you find there is no fuel in the bowl after sitting, you'll need to inspect the main body for leakage.

You will also want to check primary vacuum break clearance, should be 0.160" and choke rod clearance should be 0.080" Choke unloader at WOT should be 0.230".

Check your fast idle, should be 1400 RPM in park.

I would recommend a full carburetor rebuild if it hasn't been done in a number of years. The Quadrajet is a very user friendly carb.

Well Im near Chicago so the temperature hasn't been above 40 since I got the car. I haven't looked at the car again, hopefully tonight. Ill try just one push to the floor and crank and see if it will start. Also, to clarify if the engine does not start, I must give it at least EIGHT pumps every time I try to re-start it! I don't want to wear out the starter, although it is already making some noises. I think its a factory Qjet, engine looks to have not been touched in years although it was used as a daily drive until 1 month ago... On the upside it is converted to R134a!!

My 472 Cadillac has about the same miles on it and was doing the same thing, counting almost 8 pumps to start it! When I took it apart, I found that the accelerator pump seal was all dried up. After rebuilding the carb it ran good.

About the 134... I use Johnson's Freeze 12. R-134 requires higher pressure on the system, meaning more opportunity for leaks, and far less efficiency than r12. I did the ac on my significant other's Pontiac with freeze 12 and it was a lot colder than the 134. It's also compatible with the original oil in the system. You can't use it with that 134 pag oil though, the oil will break down and probably a lot of other things with it.

To verify accelerator pump operation, simply remove the air cleaner lid, and look into the center of the carb. Have someone depress the throttle (engine off please) and at the same instant, you should see 2 distinct strong squirts of fuel into the front section of the carb. If a delayed squirt or a weak squirt or none at all, you at least need a new accell. pump. The newer drier fuel will wear out the pump if not the age of the car as well.

I Have to agree with jjm 01. I recently rebuilt my Rochester carb, and I press the accelerator once to engage the choke and she starts first time everytime. lowest she has been this year is 20f and the same thing one press to engage the choke and she starts immediately.

Thanks guys, although I'm probably going to end up just getting a whole new carb eventually. Although today it was around 42 degrees and it only took 3 times to get her going. I will check the acclerator pump, too.