Carter 4 Barrel Top Cover Leaking

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Ken Pevay

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Ludlow, Ma
On my 67 Barracuda, I got the original Carter AFB - 4295S rebuilt. rungasket materals and perfoms great. However after i drive it and put it back in the garage I noticed a strong gas smell. come to fine out the gasket for the top of the carberator in the rear was leaking. I went back to where I had it rebuilt and they retorqued the screws but it continues to see what seemingly appears to be wicking through the gasket material. Has any one encountered this? the shop suggested we double up on the gaskets using two to maybe address any imperfectons in the surfaces. I haven't wanted to take it appart to inspect it till I had a replacement gasket. does any one know of a source to get just the gasket I need without buying a whole kit at the $110 plus or minus.

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Not a Holley. That's a slap in the face. The float level is probably too high. What's your fuel pressure?
 
Not a Holley. That's a slap in the face. The float level is probably too high. What's your fuel pressure?
Yup it is a Carter, my former hot rod had a Holly, I have not checked the float level yet but will do that when i open it up.
 
IIRC the fuel level should not be above the top of the bowl.

You should be able to remove the cover with the bowls full UNLIKE a Holley.
 
I agree float level may be too high. Another possibility is it might be cooking the fuel in the bowl due to heat soak. Can you run a thermal blocking gasket between the carb and the mounting surface on intake? They are sometimes made out of pressed paper, plastic, or mycarta. Watch for hood clearance, and possibly changing the choke settings.
 
Another possibility is it might be cooking the fuel in the bowl due to heat soak
Wouldn't that turn the fuel to vapor, rather than over fill the bowl?

Now maybe the fuel in the fill line is vaporizing and expanding pushing additional fuel into the bowl?

My bet is on high float levels.
 
Wouldn't that turn the fuel to vapor, rather than over fill the bowl?

Now maybe the fuel in the fill line is vaporizing and expanding pushing additional fuel into the bowl?

My bet is on high float levels.
It can literally boil the fuel in the bowl, especially now with all the ethanol in the fuel. You know how a pot can boil over. Well, so can a float bowl.
Now I will agree with your suggestion about boiling the fuel line fuel & fuel pressure should not be excessive. Those are a real possibility, too. Especially considering how weak the Carter needle/seat are in sealing. When/if you take the bowl cover off, you should check that the seats are screwed in all the way, tightly. You don't have to go crazy on them, but they have to be tight.
 
[1] Fuel slosh is going to 'wet' the gasket, even with the correct float level.
[2] The airhorn could be warped.
[3] Do NOT use an extra AH gasket as it changes the position of the met rods in the jets. If the shop suggested this, find another shop...
[4] In the pic, there is a small hole below the centre screw. Could that be the leakage point? I think it is just a vent, do not know why it is needed, maybe anti percolation vent. You could try blocking it off.
 
Ditto on Mike's Carburetor Parts. You can buy a bowl gasket for $5 and the full kits aren't $110. Also, your accelerator pump linkage is on backwards. When viewing from the front you should see an "S" not a "Z".
 
On my 67 Barracuda, I got the original Carter AFB - 4295S rebuilt. rungasket materals and perfoms great. However after i drive it and put it back in the garage I noticed a strong gas smell. come to fine out the gasket for the top of the carberator in the rear was leaking. I went back to where I had it rebuilt and they retorqued the screws but it continues to see what seemingly appears to be wicking through the gasket material. Has any one encountered this? the shop suggested we double up on the gaskets using two to maybe address any imperfectons in the surfaces. I haven't wanted to take it appart to inspect it till I had a replacement gasket. does any one know of a source to get just the gasket I need without buying a whole kit at the $110 plus or minus.

View attachment 1715969574

View attachment 1715969575

View attachment 1715969576
$110 for a kit? Horse feathers!
KT-5039A - CARB KIT C4 Listed on that same page are the individual top gaskets.
 
So sorry for using the Holly swear word, hope you guys can cut a 70 year old guy some slack. Reset the float levels they were a little off a bit low if anything. What it did discover is that the back two screws had no washers and those screws might have been bottoming out in the holes as they are dead eneded. After a test ride it seems to be better just a little damp, I will order and reolace the gasket and see where that takes me. So pleased for all the responses and information you guys continue to be a great sorce of information and I thank you for that. Its ok that you busted my balls abouth the Holly thing.
 
So sorry for using the Holly swear word, hope you guys can cut a 70 year old guy some slack. Reset the float levels they were a little off a bit low if anything. What it did discover is that the back two screws had no washers and those screws might have been bottoming out in the holes as they are dead eneded. After a test ride it seems to be better just a little damp, I will order and reolace the gasket and see where that takes me. So pleased for all the responses and information you guys continue to be a great sorce of information and I thank you for that. Its ok that you busted my balls abouth the Holly thing.
Good to hear your "non Holley" is on the mend. Yes, screw length (or lack of washer) could aggrevate a possible leak. Carter/Edelbrock carbs aren't supposed to have fuel above the float bowl.
 
I have the same carburetor, except for a four speed, 4294S.

I had the same issue, the float level was too high. I pulled the top off, reset the float and it fixed the overflowing issue.

On another note, I also had a strong smell of gas in the garage after driving my car. I started using no alcohol premium gas. My garage still smells a little but no alcohol gas made a big improvement.
 
I have the same carburetor, except for a four speed, 4294S.

I had the same issue, the float level was too high. I pulled the top off, reset the float and it fixed the overflowing issue.

On another note, I also had a strong smell of gas in the garage after driving my car. I started using no alcohol premium gas. My garage still smells a little but no alcohol gas made a big improvement.

I have adjusted the float and went for a 50 mile ride on sunday with little or no gas smell when I got home, still a little damp to yhe touch. I have two gaskets on order one has a widw back and one is narrow and follows the out side of the back of the carb, not sure which one would be better or the right one. Il'll post some pics when I get them to see what you think. Thanks for the feedback.
 
Sounds like you got it figured out!! Some pics of yours once you get the new gasket on would be nice!
 
I looked and looked but it seems no one makes the good blue style gaskets for them like Holleys. Those type gaskets will not wick fuel.
 
Using a thick AH gasket changes the met rod position in the jets.
 
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