Q-Jet question ??
Thread Starter
Drifting
Joined: May 2005
Posts: 1,909
Likes: 6
From: Lake Arrowhead - Georgia > 72 Base Coupe & 74 BB Roadster
Q-Jet question ??
I was fortunate enough to have my original 72 base 350 / Qjet rebuilt by Lars about 9 months ago. The outcome was AMAZING. Best running 350 Vette I have ever had.
This morning.....after sitting for about 2 weeks, it still cranks right up....after warm up, the choke drops off and idles perfect at 900 rpm...BUT when I place into Drive....it chokes dead within 10 seconds. I am about to check my dwell (ignitor II ?) and my timing. If that checks ok.....
Where do you suggest to start on the Carb ??
Thanks........
This morning.....after sitting for about 2 weeks, it still cranks right up....after warm up, the choke drops off and idles perfect at 900 rpm...BUT when I place into Drive....it chokes dead within 10 seconds. I am about to check my dwell (ignitor II ?) and my timing. If that checks ok.....
Where do you suggest to start on the Carb ??
Thanks........
Le Mans Master
Joined: Nov 2001
Posts: 8,831
Likes: 1,959
From: LONG ISLAND
2025 C3 ('68-'73) of the Year Finalist - Unmodified
2024 C3 of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
I was fortunate enough to have my original 72 base 350 / Qjet rebuilt by Lars about 9 months ago. The outcome was AMAZING. Best running 350 Vette I have ever had.
This morning.....after sitting for about 2 weeks, it still cranks right up....after warm up, the choke drops off and idles perfect at 900 rpm...BUT when I place into Drive....it chokes dead within 10 seconds. I am about to check my dwell (ignitor II ?) and my timing. If that checks ok.....
Where do you suggest to start on the Carb ??
Thanks........
This morning.....after sitting for about 2 weeks, it still cranks right up....after warm up, the choke drops off and idles perfect at 900 rpm...BUT when I place into Drive....it chokes dead within 10 seconds. I am about to check my dwell (ignitor II ?) and my timing. If that checks ok.....
Where do you suggest to start on the Carb ??
Thanks........
float level ? is it getting enough fuel ? or maybe a vacume issue ?
Team Owner
Joined: Oct 2001
Posts: 23,121
Likes: 301
From: Do or do not there is no try YODA
I'm guessing that the needle and seat is hard from sittng, or the float is stuck and causing fuel to bleed over. It is in effect flooding itself by not shutting the fuel off with the float/needle and seat. Drive it more!!
Le Mans Master
Joined: Nov 2001
Posts: 8,831
Likes: 1,959
From: LONG ISLAND
2025 C3 ('68-'73) of the Year Finalist - Unmodified
2024 C3 of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
Thread Starter
Drifting
Joined: May 2005
Posts: 1,909
Likes: 6
From: Lake Arrowhead - Georgia > 72 Base Coupe & 74 BB Roadster
OK....It looks like the Timing Fairy was with Santa this year. The timing was dropped to +2. I reset it up to about 12 and adjusted the idle. Seems OK now. I am going to attempt the drive to the gas station and top it off. It's showing almost empty.
Maybe I SHOULD drive it more...........
Thanks Y'all.........
Maybe I SHOULD drive it more...........
Thanks Y'all.........
Tech Contributor
Joined: Aug 1999
Posts: 14,382
Likes: 6,401
From: At my Bar drinking and wrenching in Lafayette Colorado
Fred -
Do you remember how to check and set up that total timing? Verify your dwell at 30 degrees, and then get that timing set back up to 36 the way we had it.
Also: Pull the hose from your vacuum advance off at the carb and suck on it - make sure that vacuum advance control unit hasn't ruptured. It should hold a vacuum.
Lars
Do you remember how to check and set up that total timing? Verify your dwell at 30 degrees, and then get that timing set back up to 36 the way we had it.
Also: Pull the hose from your vacuum advance off at the carb and suck on it - make sure that vacuum advance control unit hasn't ruptured. It should hold a vacuum.
Lars
Thread Starter
Drifting
Joined: May 2005
Posts: 1,909
Likes: 6
From: Lake Arrowhead - Georgia > 72 Base Coupe & 74 BB Roadster
Fred -
Do you remember how to check and set up that total timing? Verify your dwell at 30 degrees, and then get that timing set back up to 36 the way we had it.
Also: Pull the hose from your vacuum advance off at the carb and suck on it - make sure that vacuum advance control unit hasn't ruptured. It should hold a vacuum.
Lars
Do you remember how to check and set up that total timing? Verify your dwell at 30 degrees, and then get that timing set back up to 36 the way we had it.
Also: Pull the hose from your vacuum advance off at the carb and suck on it - make sure that vacuum advance control unit hasn't ruptured. It should hold a vacuum.
Lars
Thanks Lars....turned out to be the timing. Your carb work is still the best thing I've ever done to this car. I will do a search for the paper on setting up the timing as you describe and get that done.
FL
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Thread Starter
Drifting
Joined: May 2005
Posts: 1,909
Likes: 6
From: Lake Arrowhead - Georgia > 72 Base Coupe & 74 BB Roadster
I hope I did this right....
....sure runs better than ever! I wonder if this same method works on a 74 LS4 ?