[John O.]

Running a 68 Quad on a 69 400. Been having issues with it and had it rebuilt using kit and parts from Cliffs. Sometime in its life someone bent the crap out of linkages on choke side. Installed the kit and epoxy to seal up the fuel well. Guy who rebuilt checked all the settings and adjustments. Surprisingly seems to run worse. Irratic idle, most of the time it will only idle at 500 rpm and then after running for about 15 min in 70 degree weather it will just go up tp 900-1000 rpm at idle. Running lean at idle no matter how much I turn screws out. Put hand over carb and she smooths out. Cant find any vacuum leak either. Was a surging problem also when drive at around 2100-2500 rpm. My question is who would u recommend to rebuild Quad since Cliff isnt doing it anymore per a conversation I had months ago with him? At my wits end with this carb and was going to buy and Edelbrock carb and spacer as I dont want to change intake. Car has ram air pans on it so height is an issue. Does anyone know if a Quad and Edelbrock carb are same height? Has anyone tried that combo?

[gtoguys]

I restore carbs on the side, and what you are describing is, the idle vent tubes are probably getting plugged with debris at the bottom. Also how much lateral movement do you get on the throttle shaft? When the base plate gets too worn by the throttle shaft, it creates a large vacuum leak. Sometimes enough to affect the idle quality. Did or have you ever remove the idle tubes? It shows you how to do it in Cliffs book. The tubes only have a .032" hole at the bottom, so they do get plugged easily if the carb has seen alot of years without cleaning.

[John O.]

Probably have less than 200 miles on rebuild. Harder to start also. have to crank 3 or 4 times to start. Before plugs were leaking at bottom of carb and guy who rebuilt said secondary pick up tubes were missing so he used the top off of another Quad. AS messed up as the other was it still ran a whole lot better than it does now. Took it off and there is some side to side play in secondary throttle shaft. Idles like crap. One minute its idling at 500 and if u run it for about 15 minutes idle will pick up to 1000. Even today and its 80 out and same thing. Let it sit for an hour and u have to hope it starts up and runs without stalling. Put your hand over top of carb and she smooths out. Seems way to lean at idle. Driving it and u punch it and she seems fine but 2 times in the last 2 days it popped through carb and if timing was off. Have it set at 10 degrees before. Running a mix of 100 leaded aviation gas and 90 ethanal free. I would put an Edelbrock and spacer on it if I knew it would fit with ram air pans. Ready to throw it at the wall.

[gtoguys]

If the top of the carb was replaced with the wrong year, it probably won't run very good either. You can call Cliff, he will help you through problems like this. But I still think the idel well tubes are plugged. You need to use a drywall srcew to pull them out. Make sure the float height is set correctly.

[John O.]

I need to find a good professional rebuilder and would prefer to have an electric choke put on it. I think Cliff said it can be done.

[gtoguys]

68-70 a body carbs have a divorced choke, so it won't be easy to put an electric choke on it. A different Q-jet with a coil on the side would be easier. What are the carb numbers on yours? I could look at your carb if you would send it to me. PM me for my phone number if you would like to go farther with this project.

[Greg Reid]

They make electric chokes for divorced apps now- https://www.carburetor-parts.com/Ele...33_p_3877.html

I wonder how thorough the guy was in following Cliff's process? Did he pull the idle tubes? Did he install throttle shaft bushings?
Sometimes a mismatched top or baseplate will leave gaps in the mating surfaces. One is warped this way, the other, that way. May have to belt sand it a few thousandths flat.

[John O.]

Carb #70282263. Other than Cliff who would you recommend to rebuild carb?

[455dan]

Just another thing to check if the idle tubes are clear and sized correctly

any chance a 1967 Q-jet intake was put on the newer 400 The kind with exhaust heat crossover in front of the primary holes

The steel separator plate is needed to keep the heat crossover from leaking exhaust into the primaries


Again just something to check, Good Luck getting the Q jet fixed.

They are a great carb when working correctly

[Sirrotica]

A member here goes by Shaker455, is doing carbs for members on this board. You might try im ing him.

Hopefully he can be of service to you.