Looking for Chevy Carb Idle Solenoid (Quadrajet)

[Docwheelhorse 2,740]

Hello All,

I put my rebuilt Quadrajet back on my Nova today (Bone Stock Low Compression 260 HP 350). Set it up just as the factory wants---600 RPM idle, 4 Degrees BTDC timing, Idle Screws @ 2 turns from bottomed... Vac Advance is connected to ported source. Car runs and drives real nice..... crisp throttle, gets up and goes just fine.

 

---BUT---

 

When I turn it off even after letting it idle for 30-45 seconds I get dieseling and plenty of it.... I end up having to let the clutch out in gear to kill it and that's No Bueno!

 

I turned the idle down to 525 but that is getting in the low range and its not happy just barely ticking over... motor is new with less than 1000 miles. I started thinking about retarding the timing to see if it helped and then a friend said---that won't do anything, you turn off the key and the timing is a non issue (Well Duh I thought...)

 

Then I started thinking about one of those idle control solenoids Chevy used to slam the throttle shut and prevent run-on when you turned the key off...

Anybody got a Quadrajet with the bracket and Solenoid on it that they want to get rid of? I will wire it to the keyswitch so when I turn the car off the solenoid will drop just like its suppose to.

 

My 1971 Nova came with one but all that stuff is long gone...

 

Thanks!!!

Tony

[Geno 1,929]

Does this have a vacuum advance?  Was it unhooked when setting the base timing?    

[zieg72 209]

Post up a picture of where it mounts and I will see.  I have at least a dozen q-jets sitting on a shelf.  I know they differ some

[Docwheelhorse 2,740]

HI, the vac advance was disconnected when the base timing was set. But I have since learned that it doesn't really matter where the timing is at the moment you turn off the key and kill the spark. Its kinda an obvious thing that I never thought about.... I went right to timing too!

 

As far as the bracket--I will try and find a good pic online to post . But when looking at the carb from the front of the car it is mounted to the top right side and the plunger contacts the same arm that the idle screw holds open. With this solenoid you remove the screw and set the plunger depth with the car running to set the idle. Turn the key off and the plunger drops and the throttle blades completely shut....

 

Thanks for the help guys!

 

Tony

[squonk 43,714]

Throttle shaft in good shape. Seen lot's of Q'J's with slop in them letting air bypass plates. Then you have to richen the idle mix to compensate. Then too much air /fuel mix leak by and engine diesels.

[Docwheelhorse 2,740]

Hi Squonk, Carb is in good shape.... I can turn the idle screw jets down to 1 turn and idle speed at 500.... sits and runs fine. But that is definitely too slow. I set the jets to 2 turns and idle to 600... just as the book says. It diesels about every other time you shut it off and I hate the racket---especially on a new motor.

 

Tony

[Coadster32 793]

Just a thought Tony,

I just overcame a run-on issue that I had with my Camaro. I was getting a little heat soaking in the carb. I added a carb spacer, adjusted nothing, and the problem went away.