Notices
C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette

Quadrajet Choke Won't Close

 
Old 06-11-2019, 10:29 AM
  #1  
69L46vert
CF Senior Member
Thread Starter
 
69L46vert's Avatar
 
Member Since: Jul 2006
Location: Buxton Maine
Posts: 501
Received 15 Likes on 14 Posts
Default Quadrajet Choke Won't Close

69 with 350. Trying to figure out why my choke will not close when engine is cold. Could it be a linkage problem or is there a way to adjust it? Typical divorced choke with the bimetal coil on the manifold. Runs excellent when warmed up. I'm sure it's something simple but don't know where to start, Thanks for any advice.
69L46vert is offline  
Old 06-11-2019, 10:56 AM
  #2  
7T1vette
CF Senior Member
 
7T1vette's Avatar
 
Member Since: Jan 2006
Location: Crossville TN
Posts: 30,774
Received 1,095 Likes on 987 Posts
Default

No photos. Can't advise without photos.
7T1vette is offline  
Old 06-11-2019, 11:08 AM
  #3  
69L46vert
CF Senior Member
Thread Starter
 
69L46vert's Avatar
 
Member Since: Jul 2006
Location: Buxton Maine
Posts: 501
Received 15 Likes on 14 Posts
Default

Some pics. Engine cold. Throttle pumped twice.


69L46vert is offline  
Old 06-11-2019, 04:58 PM
  #4  
71 Green 454
CF Senior Member
 
71 Green 454's Avatar
 
Member Since: Jun 2006
Location: Tampa Florida
Posts: 4,048
Received 184 Likes on 156 Posts
Default

The first thing I would do is test the choke spring to see if it's trying to pull down when cold. Also make sure that the choke rod is connected.
71 Green 454 is offline  
Old 06-11-2019, 05:23 PM
  #5  
lars
Tech Contributor
Support Corvetteforum!
 
lars's Avatar
 
Member Since: Aug 1999
Location: At my Bar drinking and wrenching in Lafayette Colorado
Posts: 10,975
Likes: 0
Received 1,129 Likes on 521 Posts
Default

Something is jammed in your linkage. Notice that the short, dog-legged rod (going from your choke shaft lever to the choke pulloff with the spring behind it) has the spring fully compressed. That spring should not be compressed - it should be pushing that lever aft and should be fully extended. The fact that it's jammed all the way forward means you have something incorrectly assembled in the choke linkage on the carb, and it's got you locked wide open.

Lars
lars is offline  
Old 06-11-2019, 06:23 PM
  #6  
69L46vert
CF Senior Member
Thread Starter
 
69L46vert's Avatar
 
Member Since: Jul 2006
Location: Buxton Maine
Posts: 501
Received 15 Likes on 14 Posts
Default

Thanks for the replies. The choke spring is pulling down but very weakly. Could it be I have the wrong length link from the choke spring? Maybe it's too long?? Not pulling down hard enough? The choke seems ok once I manipulate the weight by hand but will remain on high idle even when warmed up until manipulated by hand again. Only then will itl revert to it's old (wrong) position.

Last edited by 69L46vert; 06-11-2019 at 06:41 PM. Reason: Added "weight"
69L46vert is offline  
Old 06-11-2019, 08:28 PM
  #7  
Kaper220
CF Senior Member
 
Member Since: May 2011
Location: Mechanicville NY
Posts: 175
Likes: 0
Received 3 Likes on 3 Posts
Default Carburetor

Believe me, Lars is the zen master of Quadrajet & Holley carbs. He made my quadrajet purr like a kitten.
Kaper220 is offline  
Old 06-11-2019, 10:36 PM
  #8  
lars
Tech Contributor
Support Corvetteforum!
 
lars's Avatar
 
Member Since: Aug 1999
Location: At my Bar drinking and wrenching in Lafayette Colorado
Posts: 10,975
Likes: 0
Received 1,129 Likes on 521 Posts
Default

Originally Posted by 69L46vert View Post
Thanks for the replies. The choke spring is pulling down but very weakly. Could it be I have the wrong length link from the choke spring? Maybe it's too long?? Not pulling down hard enough? The choke seems ok once I manipulate the weight by hand but will remain on high idle even when warmed up until manipulated by hand again. Only then will itl revert to it's old (wrong) position.
See my note above in post #5. Your choke coil is pulling down, as evidenced by the rod being in the bottom of the attach slot. The lever is not moving because it is incorrectly assembled or jammed.
Lars

Last edited by lars; 06-11-2019 at 10:38 PM.
lars is offline  
Old 06-12-2019, 07:06 AM
  #9  
69L46vert
CF Senior Member
Thread Starter
 
69L46vert's Avatar
 
Member Since: Jul 2006
Location: Buxton Maine
Posts: 501
Received 15 Likes on 14 Posts
Default

Thank Lars. I'll look at it again today.
69L46vert is offline  
Old 06-12-2019, 10:30 AM
  #10  
69L46vert
CF Senior Member
Thread Starter
 
69L46vert's Avatar
 
Member Since: Jul 2006
Location: Buxton Maine
Posts: 501
Received 15 Likes on 14 Posts
Default

Following up. The problem seems to be solved. This morning I shortened the choke rod (from the bimetal coil) about 3/16", maybe 1/4". It was pulling down but just barely. The fact that the lever was not down as far as it should have been when cold was causing the linkage to jam so I never had any choke or fast idle. BTW I bought this rod from a reputable Corvette house. Simply not the right one. I had never used the car in cold weather since rebuild so it wasn't very noticeable. Today after the alteration the car started and I had fast idle which gradually decreased just like it's supposed to. I'm waiting now for it to cool down again and retest. Thanks to all for the help and ideas.
69L46vert is offline  
Old 06-12-2019, 05:15 PM
  #11  
sunflower 1972
CF Senior Member
 
sunflower 1972's Avatar
 
Member Since: Sep 2016
Location: Wauconda IL
Posts: 449
Received 70 Likes on 60 Posts
Default

Glad you got it figured out. I used this to help me when I needed to adjust mine a few years ago:https://www.hemmings.com/blog/articl...ke-adjustment/
sunflower 1972 is offline  
The following users liked this post:
69L46vert (06-13-2019)
 


Thread Tools
Search this Thread
Quick Reply: Quadrajet Choke Won't Close


Contact Us - About Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: