Terrible Idle. What’s wrong.
Race Director
Joined: Mar 2016
Posts: 14,402
Likes: 8,209
From: Napa Valley California
Years ago I attempted to rebuild a couple of QJets that were original to two of my cars.
They looked pretty and I used the GM rebuild kits but, I ended up butchering the rebuilds so bad I ended up tossing them and buying new ones.
This was back when you could walk into a GM dealership and buy the correct new part over the parts counter.
If you are unsuccessful send it to Lars, and don’t bend or toss anything, even if it comes with a new part in the rebuild kit.
Good luck!
Last edited by OldCarBum; Dec 18, 2022 at 08:47 PM.
Le Mans Master
Joined: Mar 2001
Posts: 5,738
Likes: 644
From: Lincoln, CA
Nice last name LOL.
When I buy a car the first thing I do is go though it.
Carb goes off for service because you never know who messed with it.
Change the plugs and wires, address the distributor if points.
Then you can set the timing knowing everything should be in good working order. I also check all the rubber lines for leaks because you can chase that for days,
When I buy a car the first thing I do is go though it.
Carb goes off for service because you never know who messed with it.
Change the plugs and wires, address the distributor if points.
Then you can set the timing knowing everything should be in good working order. I also check all the rubber lines for leaks because you can chase that for days,
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
Actually, you always want to do it the other way around: If you can get the engine running at all, always set the timing up first before you ever touch the carb. As I say half-jokingly, "90% of all carb problems are ignition problems." It's not far from the truth. You cannot tune a carb to compensate for timing problems, so you want to make sure timing and ignition are spot-on before doing any carb work. Also, keep in mind that the timing affects the carb, but the carb does not affect the timing. Attempting to get a carb running well before the timing has been correctly set up will result in chasing your tail all over the place. So always set up the timing first, and then do the carb work. It will make your carb tuning and setup much easier. If it doesn't run well, you will then have more confidence that the issues actually lie with the carb and not with the timing.
Lars
Le Mans Master
Joined: Aug 2006
Posts: 7,426
Likes: 1,559
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Ask Lars to send you his Technical Information Bulletin on:
How to set your timing for peak performance.
How to set your timing for peak performance.
