Just asking do u know their is a 800 cfm and 750 cfm and do u know what one u haveHey guys, what’s up.
I’ll get into more particulars of my issue with this QuadraJet later in this thread, but for right now, a simple question:
Is it possible to have a QuadraJet run on the primary circuit rather than the idle circuit?
My car WILL NOT idle on its own after starting it, even if it’s already up to operating temperature. It just stalls. If I very carefully feather the gas and hold the rpms around 800-1000 where it should idle, the engine sounds normal and you can hear the lope of the cam as you should.
But as soon as I take my foot off the gas it just stalls.
The only way I can get it to stay running on its own is if I rev it to 3500-4000 rpm, then it’ll stay running but it’s pig rich and doesn’t sound like it should. Revving it to anything less than these rpms won’t keep it running.
Once it does stay running this way, I can drive the car around for hours through start and stop traffic, and it pulls good throughout the rpm range but as soon as I shut it off and go to restart it the cycle starts all over again.
It’s almost as if when I rev it into this rpm range, it fools the carb into running on the primary circuit rather than the idle circuit. Is this possible?
I’ve gone through countless hours and trouble shooting only to find nothing out of the ordinary. It’s recently been rebuilt, no vacuum leaks, throttle shafts have been bushed, tinkering with the timing and vacuum advance pulloff locations has no effect on the problem. It seems to be an issue with the idle circuit, but unable to determine what. The idle mixture screws are turned out the recommended 3-3 1/2 turns.
The carb was thoroughly cleaned and air blown through all the passages when it was rebuilt, so dirt or contamination is highly unlikely. And yes, I have already bought the Doug Roe QuadraJet book. I see no mention of the problem I’m experiencing in it.
Please help before another QuadraJet finds its way onto the scrap heap. I’m at my wits end with it.
I believe that is the 80's truck thing, using electronic's to control the third metering rod. Donovan is there an extra auxiliary metering rod?Nice work- it looks great. See? At first everyone is intimidated by a Q-jet. But once you dig in and rebuild one several times it gets easy. Then you wonder what all the fear was for. So once the timing is verified start on the carb. A nice trick is to pull out all the plugs and ground the wires. Then have someone crank the motor while you watch the timing light. Now you can set the timing at like 100 rpm and it will not have any advance interfering. When ready, start out at a fast idle and the let it warm up. Then slowly idle down to where you want it. The final adjustment should be while watching the vacuum gauge looking for the most vacuum you can get at a reasonable idle speed. I am confident you will be successful. EDIT: what is that large object above the float bowl on the pass side? That spot is usually used for a high altitude aneroid, the CCC connector, or on some '80's trucks- an idle enrichment solenoid.
Nice work- it looks great. See? At first everyone is intimidated by a Q-jet. But once you dig in and rebuild one several times it gets easy. Then you wonder what all the fear was for. So once the timing is verified start on the carb. A nice trick is to pull out all the plugs and ground the wires. Then have someone crank the motor while you watch the timing light. Now you can set the timing at like 100 rpm and it will not have any advance interfering. When ready, start out at a fast idle and the let it warm up. Then slowly idle down to where you want it. The final adjustment should be while watching the vacuum gauge looking for the most vacuum you can get at a reasonable idle speed. I am confident you will be successful. EDIT: what is that large object above the float bowl on the pass side? That spot is usually used for a high altitude aneroid, the CCC connector, or on some '80's trucks- an idle enrichment solenoid.
I’m off Friday and light duty tomorrow so I’ll keep an eye on this want to know how you come out
Does it have plastic or brass floats
Just asking do u know their is a 800 cfm and 750 cfm and do u know what one u have
I believe that is the 80's truck thing, using electronic's to control the third metering rod. Donovan is there an extra auxiliary metering rod?
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