Cliff's Quadrajet Parts and Rebuild Kits
Quadrajet Problem Solving => Diagnose a Quadrajet carburetor problem => Topic started by: SuperRegal82 on August 04, 2012, 07:23:34 PM
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Trying to get the quadrajet sorted out on my Regal.
First, the car...
1982 Buick Regal 3.42:1 rear axle ratio TH350 trans
The engine:
GM crate "stock replacement" 350 (Chevy) low compression ( around 8.5:1), mild cam (unsure of exact specs but it's not too crazy), headers, dual exhaust, Edelbrock performer air gap intake.
The carb:
7045213
Primary Jets: 68 Primary rods: 35 (I don't have a good way to measure any of the air bleeds right now... I am assuming a set of small drill bits would be a good measuring tool?)
The back-story:
Bought the car from a friend who picked it up almost on accident at a storage shed auction. I have no idea about the car's history. It came with a small Holley that was loaded with all the typical Holley problems... ran good on the track but poorly on the street and changed it's mind based on the weather... That just wouldn't work on a street car...
The carb story:
A friend had a freshly rebuilt Q-jet that he hadn't had on a car since the late 90's. Was stored in his shop and looked as clean today as it did when he boxed it up... Cleaned it out with carb clean and looked it over. Was as clean on the inside as it was on the outside. Bolted it up and set the idle mixture and it runs OK... better than the Holley.
The problem:
Bad hesitation on the primaries. Sometimes accompanied by a backfire through the carb when cold. Performance improves as car warms up. WOT from a stop or lower speeds = hesitation. WOT from higher speeds (2500+) = smooth transition into secondaries with no hesitation. Revving car in park with accel pump disconnected = really really bad stumble/stall. To me it acts like it's lean.
Your advice would be greatly appreciated...
Thanks,
Jon
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Replace all the internals with modern components with one of our rebuild kits. The modern fuel requires high quality Viton parts, especially the accl pump. I would imagine the accl pump seal is not doing a good job with this new fuel.....Cliff
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Looks like I will be needing an SR kit...
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Sent in a request for an SR kit...
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The best way to purchase kits are to call the shop directly, 740-397-2921....thanks....Cliff
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Kit ordered. Thanks :)
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SR kit "installed", car runs much better. Still have a slight flat spot though. It will take off good, but then will "flatten out" for a second before picking up again. The bad accel pump hesitation is 100% gone, just gotta get rid of the flat spot now. Any tips on where I should look next?
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Laying down at full throttle then picking back up?
That would be a fuel delivery issue....Cliff
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Fuel delivery... makes sense... will check that out...
Thanks
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Or it could be timing... I just discovered I have no mechanical advance at all... that would explain alot...
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That will certainly hurt engine power and poor accelleration....Cliff