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

choke question

Thread Tools
 
Search this Thread
 
Old Jun 3, 2018 | 05:15 PM
  #1  
pauls71stingray's Avatar
pauls71stingray
Thread Starter
Instructor
 
Joined: Sep 2014
Posts: 156
Likes: 8
From: Allentown Pa.
Default choke question

This is such a simple system that I'm embarrassed to have to ask this. I had my carb rebuilt by Lars, so I'm sure it's right. After reinstalling the carb I found that there is no choke. Ok, so I order a replacement choke t-stat and install it. No change! I found that I have to bend the choke rod beyond 90 degrees to get the plates to close. If I'm understanding this correctly the spring pulls the linkage down and unwinds as it warms up? This is reverse to what I expected.

I'm I on the right track or should I just buy a bicycle and park the car?

TIA Paul
Reply
Old Jun 3, 2018 | 06:19 PM
  #2  
lars's Avatar
lars
Tech Contributor
Supporting Lifetime Gold
25 Year Member
Conversation Starter
Photogenic
Top Answer: 3
 
Joined: Aug 1999
Posts: 14,380
Likes: 6,391
From: At my Bar drinking and wrenching in Lafayette Colorado
Default

The choke coil and rod, when cold, pulls downwards on the choke lever, and will fully close the choke until the choke pulloff cracks the choke open upon engine start. As the coil warms up, the rod is pushed upwards, opening the choke. The rod and the choke are not part of the carb - they are part of the intake manifold, and they must be correctly adjusted per the process outlined in the Shop Manual in order for the choke to work. Your carb was tested and verified with the choke system, the fast idle, cold choke-on air/fuel mixture, and choke pulloff. All aspects of your choke system are working perfectly, but it cannot operate without the choke coil and rod properly functioning and set up. There was likely an issue with your choke coil and linkage before you sent me the carb, since somebody had cut off and disabled the choke pulloff spring in order to force the choke to open without your choke coil operating correctly.





Lars

Last edited by lars; Jun 3, 2018 at 06:57 PM.
Reply
Old Jun 3, 2018 | 08:09 PM
  #3  
pauls71stingray's Avatar
pauls71stingray
Thread Starter
Instructor
 
Joined: Sep 2014
Posts: 156
Likes: 8
From: Allentown Pa.
Default

Originally Posted by lars
The choke coil and rod, when cold, pulls downwards on the choke lever, and will fully close the choke until the choke pulloff cracks the choke open upon engine start. As the coil warms up, the rod is pushed upwards, opening the choke. The rod and the choke are not part of the carb - they are part of the intake manifold, and they must be correctly adjusted per the process outlined in the Shop Manual in order for the choke to work. Your carb was tested and verified with the choke system, the fast idle, cold choke-on air/fuel mixture, and choke pulloff. All aspects of your choke system are working perfectly, but it cannot operate without the choke coil and rod properly functioning and set up. There was likely an issue with your choke coil and linkage before you sent me the carb, since somebody had cut off and disabled the choke pulloff spring in order to force the choke to open without your choke coil operating correctly.
Lars
Lars, thanks for the clarification. I was not implying that you had anything to do with my choke not working. I know from our discussions that someone messed with the carb before I got it.

I understand that the choke t-stat and rod aren't part of the carb itself. I was just confused as I thought that the system worked in reverse of what it actually does.

Thanks again! Paul
Reply
Old Jun 3, 2018 | 09:12 PM
  #4  
lars's Avatar
lars
Tech Contributor
Supporting Lifetime Gold
25 Year Member
Conversation Starter
Photogenic
Top Answer: 3
 
Joined: Aug 1999
Posts: 14,380
Likes: 6,391
From: At my Bar drinking and wrenching in Lafayette Colorado
Default

If you crack your throttle open slightly, you can use your finger to move the lever at the choke rod attach hole up and down - you can see the choke move through its full range and see what direction the rod must move in order to actuate the choke in both directions. The only Q-Jet choke that works opposite is the 1968 427 Q-Jet, which closes the choke when the rod moves up, and opens it as the rods pulls down. Holley is also opposite of the Q-Jet.

Lars
Reply

Get notified of new replies

To choke question





All times are GMT -4. The time now is 02:09 PM.

story-0
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-1
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-2
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-3
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-4
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-5
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-6
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-7
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-8
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-9
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE