Holley nh carburetor?

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Bigcth61
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First Name: Tim
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Holley nh carburetor?

Post by Bigcth61 » Sun Jun 08, 2025 4:08 pm

I have a leak at the bottom of the bowl where the drain plug is. I have replaced the gasket and it still leaks. Any suggestions are greatly appreciated. With the price of gas I’m going broke.


speedytinc
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Re: Holley nh carburetor?

Post by speedytinc » Sun Jun 08, 2025 4:13 pm

Determine EXACTLY where the leak is coming from. Drain plug? Tighten & tap to reseat. Bowl bent in? straighten.
Sure its not the needle & seat slightly weeping & overfilling the bowl? A little EZ turn on the bowl drain gasket could do it.
Last edited by speedytinc on Sun Jun 08, 2025 4:29 pm, edited 1 time in total.


jab35
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Re: Holley nh carburetor?

Post by jab35 » Sun Jun 08, 2025 4:14 pm

Is the bottom of the bowl seated tightly against the carb body? that needs to be tight to achieve a permanent seal.


Topic author
Bigcth61
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Re: Holley nh carburetor?

Post by Bigcth61 » Sun Jun 08, 2025 4:27 pm

Yes the bowl is tight against the bottom it’s coming out right at the bottom where the drain screws in. I wish it was at the top though then it would probably be the float or the bowl gasket and those are both ok.


Topic author
Bigcth61
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Re: Holley nh carburetor?

Post by Bigcth61 » Sun Jun 08, 2025 4:33 pm

I ordered a new bowl from Snyders thinking it was bent. So I might beat on this one lol.


jab35
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Re: Holley nh carburetor?

Post by jab35 » Mon Jun 09, 2025 2:02 pm

And the flange on the brass nut is flat against the gasket and the gasket flat against the outside of the bowl? Threads in the carb body clear to allow brass flange fitting to compress bowl and gasket against carb body? And you're certain bowl drain valve is not weeping when closed? If yes to all, I'd make sure all surfaces were clean and lightly apply some gasoline resistant gasket seal to the bowl bottom and both sides of gasket and the brass flange and reassemble everything. good luck, jb


J1MGOLDEN
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Re: Holley nh carburetor?

Post by J1MGOLDEN » Mon Jun 09, 2025 4:42 pm

I had a hair from the original fuel line gasket get cought in the needle valve, so the bowl never shut off and kept leaking for quite some time.

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Craig Leach
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Re: Holley nh carburetor?

Post by Craig Leach » Fri Jun 13, 2025 2:21 am

Hi Tim,
Had someone with this issue on a tour once, took two to three feet of Teflon tape, hold it between your thumb & index fingers and spin it
into a string, fold it over & spin it again. Turn the gas off, take the bowl nut loose & wrap the Teflon string around the stem between the bowl
& nut in the direction that it tightens in & snug up the nut. This will fill the irregularity's in the bowl, nut & carb. Turn the gas ack on & see?
Craig.

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Mark Gregush
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Re: Holley nh carburetor?

Post by Mark Gregush » Sun Jun 15, 2025 11:18 am

Part of the problem could be the material used to make some of the gaskets is too hard so does not compress and fill the voids/irregularity's as one would like. Noticed that with the gasket for the float valve, make my own out of lead and have had less issues.
I know the voices aren't real but damn they have some good ideas! :shock:

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Steve Jelf
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Re: Holley nh carburetor?

Post by Steve Jelf » Sun Jun 15, 2025 11:52 am

Mark's comment reminds me that replacement float valves in particular were notorious for the too-hard gaskets that came with them. I made a better one with gasket paper. This is separate from the other common float valve problem of too small an opening which leads to fuel starvation.
The inevitable often happens.
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