Cliff's Quadrajet Parts and Rebuild Kits

Quadrajet Problem Solving => Diagnose a Quadrajet carburetor problem => Topic started by: gordr on June 10, 2014, 01:32:42 PM

Title: replace 71 jets with 74s? For fixing off idle stumble....
Post by: gordr on June 10, 2014, 01:32:42 PM

I've got a 7037211 Quadrajet on my 67 machine. I've had an off-idle stumble for quite awhile. A friend gave me a couple of size 74 jets. We figure I'm running lean now. So, should I go ahead and put those 74 jets in there to richen it up?

Title: Re: replace 71 jets with 74s? For fixing off idle stumble....
Post by: 77cruiser on June 11, 2014, 05:05:03 AM

Does it stumble under load? Will it do it in neutral by just easing into the throttle?

Title: Re: replace 71 jets with 74s? For fixing off idle stumble....
Post by: gordr on June 12, 2014, 08:20:18 PM

it stumbles mainly under load. Just going off idle in the low rpms then when it gets to above 2200 rpm and if I press the gas harder then the secondaries kick in nicely.

I neglected to mention in my first note that when feathering the pedal and keeping the speed steady in the city the car feels like it's got a slight push-pull attitude on it, so I'm guessing that's part of the same problem.

Title: Re: replace 71 jets with 74s? For fixing off idle stumble....
Post by: Cliff Ruggles on June 20, 2014, 06:59:01 AM

71 main jets are PLENTY for that carb number.  I'd install one of our kits, making sure the hanger arms are exactly even and level. 

Those carbs aren't known for being lean on the primary side, so a good rebuild/cleaning/modern components would be the first thing to do, they re-evaluate and reduce the metering rod diameter if/as needed....Cliff