6T7L71CPE

Save the LEAKING HOLLEY JOKES!!!

My carbs were restored by Holley several years ago. A couple years
later the end carbs started to soak the throttle body gasket and carb
base gasket after it cools down. This is well after it has cooled down
and is not heat soak boil over. This may be worse in the winter. I checked and it is not coming from the boosters, it appears to come from the idle circuit openings. It does not leak around bowl sealing surface. I've looked at the mating surfaces of the gaskets and they appear to be sealing the idle circuit passages. The clutch head screws were not loose. Any idea why this does this and how to fix it?
THANKS

Crazyhorse

Maybe one of the surfaces has warped, from what I've read it's a fairly
common occurance and I suspect the same thing with mine.

I replaced all the gaskets and it still leaked.

Stopped by my machinist who also sells used parts and he had a old 1850.
I bought it for $40 and rebuilt it with all the same gaskets that I just used on my orig carb.

It works great and no more leaks !!

6T7L71CPE

The body isn't warped but has some pitting on non critical places. I'm not real impressed with Holleys "restoration", they didn't mill the surface. Hopefully some new blue type gaskets will keep it dry.

JohnZ

Milling the bottom surface and the metering block mating surface dead flat on the main body is an absolutely essential part of a proper Holley rebuild/restoration; not milling those surfaces is frequently a recipe for leaks.

6T7L71CPE

Would milling these be something a competent automotive machinist should be able to do or is it too specialized? Thanks

JohnZ

Sometimes careful work with a flat file and a good straightedge is adequate, but any machinist with a Bridgeport can do it.

6T7L71CPE

I went at the carb body with a file and sandpaper. I had a 4” square X 1” thick granite sample for a sanding block. I found that one of the idle openings was actually a low spot. This is my theory: Mine leaked well after they cool down, I’ve checked them after a couple hours when the intake/carb are around 65 degrees, no leaking. The next day when it’s down to about 45 degrees and the throttle body and base gasket are wet. I think the gas is leaking into the idle circuit through the gasket on the metering plate after shrinking from cooling down. The idle circuit opening is the only opening below the fuel level. Once it leaks from here it can wet the two gaskets. Hopefully this will cure it. Notice how Holley barely cleaned the pitted surface; the plating didn’t even take to the real bad areas.