Issue with Quadrajet
Thread Starter
8th Gear
Joined: Jul 2018
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Issue with Quadrajet
70 - 350/350. Rebuilt carb myself. Followed video and articles. Detailed cleaning, replaced accelerator pump, float other parts via a kit, made adjustments.
Issue now is when starting after a few minutes cannot be in garage with doors open while car is running. Eyes start to get irritated and smell is not great. See moisture seeping slightly from gaskets. Tried adjusting air/fuel twice with vacuum gauge to manifold connection.
Any suggestions. Thanks.
Issue now is when starting after a few minutes cannot be in garage with doors open while car is running. Eyes start to get irritated and smell is not great. See moisture seeping slightly from gaskets. Tried adjusting air/fuel twice with vacuum gauge to manifold connection.
Any suggestions. Thanks.
Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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Mine is like that too so that could be normal but......getting fuel coming through the gaskets is not. Have you tried retorquing the screws to insure they are tight enough. And have you tried wiping the gasket to see if its condensation or fuel? when you screw in the idle screw is it making the car stumble?
my biggest, new issue is fuel boiling from being in the bright sun at car shows with the hood open. I need to carry starting fluid to start my car now. Otherwise its not a problem
my biggest, new issue is fuel boiling from being in the bright sun at car shows with the hood open. I need to carry starting fluid to start my car now. Otherwise its not a problem
Thread Starter
8th Gear
Joined: Jul 2018
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I will check ignition timing tomorrow.
Did retorque carb and mounting nuts. One of the bolts in center won't lock down totally tight, screws in but keeps turning, (any thoughts of how to get it tight), rest are fine. I'll check moisture and yes can get it to stumble with idle screw.
I'm thinking about removing carb and opening it back up to check everything including float level.
Any others thoughts are welcome.
Thanks for responses.
Did retorque carb and mounting nuts. One of the bolts in center won't lock down totally tight, screws in but keeps turning, (any thoughts of how to get it tight), rest are fine. I'll check moisture and yes can get it to stumble with idle screw.
I'm thinking about removing carb and opening it back up to check everything including float level.
Any others thoughts are welcome.
Thanks for responses.
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,108
Likes: 9,236
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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that sounds like a good idea. I dont know about the stripped screw, you may have to send it to Lars for repair
Thread Starter
8th Gear
Joined: Jul 2018
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I just checked moisture on gaskets and it is gas.
Looking like I should check float and see where we go from there.
Thanks and any additional thoughts welcome.
Any suggestions on rebuilders? I've seen Jet online and Lars in this thread.
Looking like I should check float and see where we go from there.
Thanks and any additional thoughts welcome.
Any suggestions on rebuilders? I've seen Jet online and Lars in this thread.
Drifting
Joined: Mar 2014
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From: Akron OH
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Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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Lars rebuilt mine!! Very good choice
Team Owner
Joined: Jan 2006
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From: Crossville TN
I don't know about kits for Holley carbs, but even the better brands of carb rebuild kits for Q-Jets come with junk paper gaskets which WILL leak if not sealed during the rebuild.
There may be other methods, but I've taken to putting on plastic gloves and working some Permatex Ultra Black RTV into the body gaskets. Just getting some onto every surface (top, bottom, edges), then wiping off all excess goo and allowing them to cure fully. Carb gaskets USED to be impregnated with something that sealed fuel IN. Gaskets appear to be nothing but paper, now. Some idiot 'bean counter' cost-reduced the gaskets, I'm sure.
Why these vendors buy junk that won't work is beyond me.
There may be other methods, but I've taken to putting on plastic gloves and working some Permatex Ultra Black RTV into the body gaskets. Just getting some onto every surface (top, bottom, edges), then wiping off all excess goo and allowing them to cure fully. Carb gaskets USED to be impregnated with something that sealed fuel IN. Gaskets appear to be nothing but paper, now. Some idiot 'bean counter' cost-reduced the gaskets, I'm sure.
Why these vendors buy junk that won't work is beyond me.
Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
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No one asked what kind of carb it is. Half of you assume its a Quad, half assume its a Holley, half assume its . . . .how many halves is that now?
If its a Holley, slight possibility of a pin hole in the Power Valve.
Ethanol loves rubber.
If its a Holley, slight possibility of a pin hole in the Power Valve.
Ethanol loves rubber.
Last edited by Rescue Rogers; Jul 22, 2018 at 09:06 PM.
Le Mans Master
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Intermediate
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When I rebuild a quadrajet I order a kit from Cliff Ruggles Racing. Give them the number off the carb and engine specs if not stock and they will put a kit together for you. I just did my '76 Trans Am and made a world of difference as they sent new jets and meter rods. They also have a forum to ask carb questions and he gets back to you with his recomendations. You also might be interested in his book " How to rebuild and modify Rochester Quadrajet carburetors" This is assuming you have a Q-jet. He does have a rebuilding service but there is a long backlog.
Race Director
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did you correctly hang the float using the small hook and hang it from the inside edge of the float pivot?
did you set the float to 1/4"? That is the recommended setting in Cliff Ruggles book.
does the power piston move freely up and down?
did you set the float to 1/4"? That is the recommended setting in Cliff Ruggles book.
does the power piston move freely up and down?
Last edited by MelWff; Jul 23, 2018 at 04:02 PM.
Race Director
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I've tried in the past to rebuild a couple of carbs and never had good results.
They would run better, but there was always a little something that wasn't perfect.
Send it to Lars and be over the headache.
He will get it right and you'll be very happy.
They would run better, but there was always a little something that wasn't perfect.
Send it to Lars and be over the headache.
He will get it right and you'll be very happy.