What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Quadrajet choke adjustment

CK5

CK5

In my underwear
Administrator
 Premium
GMOTM Winner
Author
Joined
May 19, 1999
Posts
24,547
Reaction score
6,480
Location
CO
Anyone good with quadrajets? If I adjust the thermostatic choke it will adjust the RPM up or down but the choke will not step down while warming up no matter what the RPM is. I havent messed with the fast idle adjustment yet because I figured I should get the choke to step down first?
And now I need a choke cover gasket as my old one fell apart when I took the cover off for a look see. Lol
 
It should fall off of the fast idle cam as you tap the throttle with the choke open. If you adjust the choke (round black cover) too far towards closed/rich it may not move far enough to disengage the fast idle. Is this electric or heat pipe? Do you have a vacuum pull-off both in front and behind the choke or only one?
 
Heat pipe with vacuum pull-off both in front and behind the choke.
 
When it's cold out and the engine is cold, the choke coil should just barely close the flap. As soon as you have engine vacuum, the one pull-off should get the flap open a little bit. As it warms, the flap should open all the way on it's own. It's possible you have the coil wound too tight.
 
Blue85 said:
When it's cold out and the engine is cold, the choke coil should just barely close the flap. As soon as you have engine vacuum, the one pull-off should get the flap open a little bit. As it warms, the flap should open all the way on it's own. It's possible you have the coil wound too tight.
Click to expand...
I started with the coil at the factory notch in the cover, could the coil just be bad?
 
does the weight with steps for the high idle move freely ?
Does the choke butterfly move when you turn the cover ?
 
Seems I have to turn it quite a bit, works great when the coil is removed and I use my finger. Lol

Does this look correct?

20240820_180730.jpg
 
Coil looks ok. Hit with a propane torch and see which way it moves.
The lever for that style should spotted, the spring goes in the slot
 
Wes Harden said:
Coil looks ok. Hit with a propane torch and see which way it moves.
The lever for that style should spotted, the spring goes in the slot
Click to expand...
Shouldn't the rear vacuum break be hooked up to a main vacuum source on the carburetor? It currently is routed to the air cleaner assembly, it might not be pulling enough vacuum to move the high idle cam rod causing it to not step down???
 
I need to look at 4mc to refresh my memory.

This an E4me but similar 20240821_091439.jpg
Rear pull off is manifold vacuum
 
  • Like
Reactions: CK5
Wes Harden said:
Coil looks ok. Hit with a propane torch and see which way it moves.
The lever for that style should spotted, the spring goes in the slot
Click to expand...
spotted? slot? you mean just under the lever?
 
Just noticed the choke heat tube from the manifold to the back of the carb was not seated in the vac line, it seemed it was just butted up to the hose instead of being in it.
 
CK5 said:
Just noticed the choke heat tube from the manifold to the back of the carb was not seated in the vac line, it seemed it was just butted up to the hose instead of being in it.
Click to expand...
Those also have vacuum port in the choke coil housing. There a seal between housing and the carb body. There is also a seal on the lever shaft to butterfly linkage in the carb body. If this seal is hard to installed crooked it may not let the shaft turn freely
 
Wes Harden said:
Slotted, I am talking about the lever inside coil cover housing
Click to expand...
That's what I thought you meant but don't see a slott. Unless you mean the 2 indents on the "D" lever?

20240821_110210.jpg
 
So there is a second cover that coil ends with it looped and it slips over the lever post.
 
  • Like
Reactions: CK5
Wes Harden said:
So there is a second cover that coil ends with it looped and it slips over the lever post.
Click to expand...
Gottcha, I thought you were saying there was a slot somewhere that the coil end fit into.
 
I just ordered a new gasket as my old one broke in pieces, for an extra 10 bucks or so I just got the whole cover/coil assembly as well.
 
Wes Harden said:
So there is a second cover that coil ends with it looped and it slips over the lever post.
Click to expand...
Wait, wouldn't the coil end go under the lever post?
 
You must log in or register to reply here.

Latest Posts

Top Bottom