Electric Choke On Quadrajet Carburetor

[demarpaint]

Originally Posted By: c3po
I will have to look at this top notch on the cam, because I cannot see anything.

This is not the original Quadrajet, I had a computer controlled 1 on there before, a new 1 would have been $1100.00, thats right eleven hundred dollars, I said no thanks and picked up a Jet Quadrajet Carburetor from Summit.

The fast idle screw is pressing on the cam, I will go out now and look for the notches.

I am taking the car out tonite because it is a balmy 53 degrees outside, I will let you know how everything goes.


IIRC there are 3 steps on that cam, you want the highest step when the engine first starts and it works down from there. I remember trying to kick them down by stepping on the gas, if it they weren't ready to come off the fast idle it was a real PIA. The proper set up takes some time, hang in there!

Frank D

 

[c3po]

I started the car up and the idle went to 1500 rpm's and stayed there for about 30 seconds.

I pulled out of the driveway and drove the car down the road and it was fine, no issues. I stopped at a place to meet some people, and decided to move the car to another spot, car started up fine when warm.

I went to leave an hour later, I set the choke by hitting the gas pedal, car started right up, but the fast idle cam did not kick the rpm's up, thats probably because the car has to be stone cold for it to work, But I will be taking the car out tommorow so I will see what happens.

When I started the car after an hour, I let it idle for 30 seconds, and then I drove away with no:

1) Stumbling
2) Bogging
3) Hesitation

It drove away fine, now my question is how often should I spray the linkages, and is it better to spray the linkages with brakleen or carburetor cleaner.

 

[demarpaint]

Usually after 1 hour you're not going to get a very fast idle, unless it's very cold outside. You might get a faster than curb idle, its all about temps. The choke linkage will be at a different position on that cam.

I would stick to carb cleaner for the inside and outside surfaces of the carb. Depending on how many miles you drive cleaning the carb every 5000 miles should be more than enough. I remember some car owners didn't clean their carbs for years. If you're doing 3000 mile OCI's clean it every other OC, you'll be fine. Sometimes to much is NG.

I'd leave it alone and drive it a few days and see what happens.

 

[c3po]

I am going to drive it around today as it is going to be getting very cold here again.

I will post back.

 

[c3po]

I had a little problem today with it going to 2000 rpm's and I could not kick it down, I turned the screw and it came down too much. I am going to have to get a 2nd person and have them start the car and then they can tell me when it is steady at 1500 to 1600 rpm's. I am not giving up and of course when the car is warmed up she runs great.

On another note, my car was not coming up to temp that quick, I took out the 7 lb. radiator cap and put in a 10 lb. cap and it is coming up to temp quicker.

I do not want to put to high a pressure radiator cap because this car has 366,000 miles and I do not need any head gasket issues. I also put in a new radiator, it is an aluminum one and has plastic tanks on it.

I will get this right.

 

[demarpaint]

I told you they could be a PIA! LOL! Keep up the good work I'm positive you'll get it.

Don't fee bad, most mechanics would be going through the same problems!

 

[c3po]

Originally Posted By: demarpaint
I told you they could be a PIA! LOL! Keep up the good work I'm positive you'll get it.

Don't fee bad, most mechanics would be going through the same problems!

This why I am not bringing it back to the mechanic, I will figure this 1 out, are the notches on the cam where the fast idle screw touches it.

I may need to get a more powerful drop light to see these notches, anyone have any pics of these notches on the fast idle cam.

 

[flanso]

Normally, the 1500 RPM fast idle speed is adjusted with the engine warm and the fast idle screw resting on the top step of the fast idle cam. When the engine is cold started, the fast idle speed will be much lower even when the fast idle adjustment screw is on the top step of the fast idle cam. Incidentally, the fast idle cam, usually brown plastic on many Q-Jets, has steps. When the choke is fully open and with the throttle open slightly, you should be able to lift the fast idle cam with your finger so the highest step is adjacent to the fast idle screw. When you take your finger off of the cam, it should drop all the way down by itself.

 

[c3po]

Whatever I did this morning seems to be working.

I was at the library for a few hours and when I went out to start the car, the idle jumped up to 2000 rpm's, it stayed there until I hit the gas pedal, it slowly went down to idle and I slowly drove away.

I will take another look at where the fast idle cam and where the fast idle screw are tommorow.

Its going down into the teens tonite, I will be taking out the Marauder which has fuel injection on it.