[75ChevyPU]

I own a 1975 Chevy PU with a new Chevy 350 V-8 crate engine . I purchased a rebuilt Quadajet 4 BBL for the new engine. It seems to run rich and trys to continue to reun after I turn off the ignition. The timing is set @ 8 BTC. In park it idles at about 1000 RPM. The engine seems to run very smooth at idle and accelerates well.
What is the correct position of the Idle mixture screws on this carb. I seem to remember that they are adjusted to 1 1/4 turns out and then fine tuned from there. Is this correct ?

[coldknock]

Originally Posted by 75ChevyPU

I own a 1975 Chevy PU with a new Chevy 350 V-8 crate engine . I purchased a rebuilt Quadajet 4 BBL for the new engine. It seems to run rich and trys to continue to reun after I turn off the ignition. The timing is set @ 8 BTC. In park it idles at about 1000 RPM. The engine seems to run very smooth at idle and accelerates well.
What is the correct position of the Idle mixture screws on this carb. I seem to remember that they are adjusted to 1 1/4 turns out and then fine tuned from there. Is this correct ?

Try a lower heat range on the plugs, better fuel, lower temp thermostat or increase initial timing 2 or 4 degrees.

Try one at a time so you'll know what works.

Larry

[willowbilly3]

Reman carbs are junk. I have NEVER bought a qaudrajet reman that even come close to being a normally functioning unit right out of the box. It is almost always easier to make your old carb work that try to get one of those POS remans to funtion right.
Run-on is almost always caused by too high of curb idle. You might try setting the idle speed down some to help get rid of that problem.

[454C10]

Adjust the idle mixture screws until max vacuum or the highest idle rpm is obtained.

[LanceM]

Just got a reman quadrajet myself a few months ago, what a nightmare, same problems as you. Found that it had jets the size of bullet holes in the primary side with little metering rods, ran super rich and had like no idle adjustment. Went to the pick and pull and yanked jets and rods out of 5-6 different carbs and have finally gotten mine rejetted where it runs really good. I wish I had the money to go and buy some more jets and rods and play around more as there is quite a selection available. There is a really good how to tune a qjet web page by Lars Grimsrud and I think I found the link doing a search on this site, I have it printed out but no site link on it. If you can find it, it will tell you everything you need to know about setting it up right.

Lance

[jimfulco]

http://www.corvettefaq.com/popular.asp should get you in the neighborhood