I rebuilt the Q-Jet on my 76 Corvette about 2 weeks ago. It is running much better but I have questions about the fuel mixture and choke adjustments. It seems like the car is running very rich. I have some liquid coming out of the exhaust system. I can't tell if it is gas or condensenation. It has been very humid in Dallas lately.

Any help would be appreciated.

Michael.

Are your floats adjusted properly? Also, on most carburetors, the adjusting screws should be about 1 1/2 turns out from the stop for a starting adjustment, then fine adjusted for optimum fuel mixture. If your engine has been modified in any way, it may need different sized jets installed.

I don't believe the engine has been modified. I used the instructions in the kit to adjust the float. The jets are set out about 3 turns right now. When I origanlly tightened them before the rebuild, they were at 4 1/2 turns out. Do you know the proceedure to make the correct adjustment?

Thanks Michael.

It does sound like the adjusting screws are too far out (running rich). To really adjust them right, unless you're one of those rare people that has "the touch" when it comes to carburetors, you should have an air/fuel ratio meter that has the probe that goes up the tailpipes.

To do it by hand without meters, etc., you have to go by the tune up information sticker in the engine bay...rpms. etc. With the engine idling, turn one screw in slowly until the engine coughs or even stops suddenly, then back out a turn and a half, then do the same to the other side. That should put you close. You may have to adjust the idle speed to where it belongs, then adjust the mixture screws again. It may take a couple of times, each time with less and less adjustment. Try that for a while and see how the engine runs and if you have any more signs of a rich mixture through the exhaust.

You may want to take the car to someone who knows carbs if you're having no luck. These days since most everything is fuel injected, fewer and fewer techs have much knowledge or experience with carburetors. It may take going to a speed shop for one.

The idle screws on a Q jet are supposed to be between 3 and 6 turns out. the 1 1/2 is for carters and edlebrocks ..... nice try gunslinger try reading the factory reapir manuals

Thanks for all the help. I seem to be running pretty well. I took it out on the highway for a short road trip and averaged about 20mpg. Not bad for an novice. I am idling about 800 in park and 600 in drive with no movement.