Carb questions
Thread Starter
Cruising
Joined: Feb 2013
Posts: 13
Likes: 0
Carb questions
Hi all new Corvette owner here.
1978 Corvette w/ L82 and Holley carb. I assume it is the quad carb as I see 4 round fixtures in the carb under the air filter. I know a bit about tuner cars but nothing non efi. I see fuel coming out of the injectors at the front of the car but the two in the back are just dry. The car sat for 6-7 years and I just recently was able to get it started and running again. Any idea why no fuel coming out or have any troubleshooting steps I can follow to see?
1978 Corvette w/ L82 and Holley carb. I assume it is the quad carb as I see 4 round fixtures in the carb under the air filter. I know a bit about tuner cars but nothing non efi. I see fuel coming out of the injectors at the front of the car but the two in the back are just dry. The car sat for 6-7 years and I just recently was able to get it started and running again. Any idea why no fuel coming out or have any troubleshooting steps I can follow to see?
Melting Slicks
Joined: May 2006
Posts: 2,590
Likes: 403
From: Nashville TN
St. Jude Donor '09
Welcome to the C3 Corvette world and Corvette Forum. I'm not familiar with the Holleys, but I think if you have vacuum secondaries, you will not see fuel injected into the other two venturi until the secondaries open up under hard acceleration. If it has mechanical secondaries, then I would think all four would be getting a gas stream. Try to identify the model number and post to help others answer your specific questions.
Race Director
Joined: May 2006
Posts: 18,664
Likes: 2,564
On the front of the airhorn assembly is the list# of the carburetor, post that so we know which Holley you have. This will help you find it
http://www.holley.com/TechService/ListNumber.asp
http://www.holley.com/TechService/ListNumber.asp
Thread Starter
Cruising
Joined: Feb 2013
Posts: 13
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Ok so I made a novice mistake, Its an edelbrock
Attached is the picture.
https://www.dropbox.com/s/kc26sf9bfeh5fl1/DSC_0007.jpg
Attached is the picture.
https://www.dropbox.com/s/kc26sf9bfeh5fl1/DSC_0007.jpg
Melting Slicks
Joined: Mar 2008
Posts: 2,023
Likes: 6
From: Austin Tx
The front smaller holes are the primaries, and the larger rear ones are the secondaries. The secondaries are not open during normal driving, they open during WOT (after the engine has warmed up, and the lockout has fallen off).
Thread Starter
Cruising
Joined: Feb 2013
Posts: 13
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Ok cool. Now the car sat with about an 1/8 tank of gas for about 7 years. I added half a can of seafoam a month ago and then 5 gallons of premium unleaded. It has issues starting but when it finally catches it runs beautifully.
Should I run the fuel down to bone dry then just replace fuel filter and be good to go?
Should I run the fuel down to bone dry then just replace fuel filter and be good to go?
Thread Starter
Cruising
Joined: Feb 2013
Posts: 13
Likes: 0
After running it all day yesterday and upping the idle a little bit and adjusting the twin screws she starts right up on the first crank. Can still tell she is running the bad gas as it hits a lull in the ignition cycle every once in a while.
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Drifting
Joined: Mar 2009
Posts: 1,253
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From: East Wenatchee (2hours from n e where) WA
[QUOTE=1978VetteL82;1583130652] I see fuel coming out of the injectors at the front of the car but the two in the back are just dry. [QUOTE]
do your self a favor dont be lookin down in there and crack the throttle. I figured that one out when I was about 13 or 14. took a couple weeks for my hair to grow back.
do your self a favor dont be lookin down in there and crack the throttle. I figured that one out when I was about 13 or 14. took a couple weeks for my hair to grow back.
Thread Starter
Cruising
Joined: Feb 2013
Posts: 13
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[QUOTE=Crepitus;1583152003][QUOTE=1978VetteL82;1583130652] I see fuel coming out of the injectors at the front of the car but the two in the back are just dry.
do your self a favor dont be lookin down in there and crack the throttle. I figured that one out when I was about 13 or 14. took a couple weeks for my hair to grow back.
LOL! I was ripping on the throttle a little bit but no flame. I do have the crud burning and a little white smoke I guess you could call it coming out of the carb but that has stopped now.
do your self a favor dont be lookin down in there and crack the throttle. I figured that one out when I was about 13 or 14. took a couple weeks for my hair to grow back.
Le Mans Master
Joined: Oct 2010
Posts: 6,922
Likes: 839
From: melbourne florida
2023 C3 of the Year Finalist - Modified
that carb along with its brother the afb were a lousy carb, but was what was available back in the day. most people dumped them for the holley.
