[Lemans64]

Thought I could smell fuel after my last drive, after parking in garage. Upon looking into it I found fuel leaking out of the bowl screws, tried to tighten and found 2 bolts starting to pull threads. I'm like WTF, I did use a 1/2 breaker bar to put this together. has been over a year since I have even touched the carb. Helicoil kit is ordered and will attempt repair tomorrow night. Anybody else seen this? Or am I just lucky and I am the only one? :no idea:

[steve25]

How much thread where the fuel bowl screws engauging in the throttle body ?

[Tom Vaught]

New carb or used carb from someone else?
How old is the carb?
Hex type bowl screws or flat blade screws?
Paper o-ring gaskets? or the POS plastic crap that never seems to seal up without gorilla torque.
Torque on screws is a very low number. like 18 inch pounds if I remember right. I go by feel.
And I tighten the screws in steps 1,4,3,2 (based off of top screws being 1 and 2 and bottom screws being 3 and 4.)
I do that 3 times GENTLY tighter each time.

Tom V.

[Lemans64]

Haven't taken float bowls and metering blocks off yet. Maybe tonight. Carb is about 5 years old, bought new. Has hex head bolts on bowls. plastic gaskets on bolts. I only use a 1/4 inch nut driver to tighten bolts and ya I know they don't get tightened real tight. was just surprised cause I don't recall having any issues last time it was apart. Googled it and it does seem to be an issue, Holley sells helicoils to repair the threads.

Thanks for input.

[Formulajones]

It's a pretty common issue. Especially on the older carbs that I like to use. As you found, heli coil kits are available and they do the job.

What I do with every holley carb, especially on one that I'm taking the bowls off frequently for adjustments, I lubricate the screw threads with Vaseline every time. Keeps from galling up the threads, it's just aluminum. Vaseline works great because if any of it gets in a fuel passage (shouldn't because you don't need much) it dissolves immediately with gas and doesn't hurt a thing.

[ta man]

Each year I replace the metering block and bowl gaskets mainly to have that fat new gasket on..I find the plastic washers on the bolts hit or miss for sealing I actually prefer the softer type they will seal great the first time. I've stripped one bolt hole in my 950hp last year after many years of service..and I'm gentle on the torque..much like Tom's technique. It happens.

[Formulajones]

Some of those plastic screw gaskets are also pretty thick, and you end up losing 2 or 3 threads of engagement. Some are so hard that it requires gorilla torque to get them to stop seeping so that's another issue with them.

Edit: I see Tom already mentioned that last part, lol.

[Tom Vaught]

5 year old carb might be aluminum or might still be ZINC. Easy to tell by the weight of the carb, ZINC is heavier. Vasoline on the threads is a great idea. Have fixed more than a few mainbodies that had a thread butchered up by over tightening trying to seal the plastic bowl seals. I can buy 500 Holley paper seals for peanuts. All good Holley kits come with them vs the plastic rings.

Tom V.

Two other comments: Never put more than 6 screws in the baseplate to mainbody. The two screw locations in the middle of the baseplate can come loose and screws fall into the intake.

Never try to install boosters in a carb without the proper booster installation tool. Same deal booster now falls into the intake/valve area.

[Formulajones]

Another issue I've found from people over tightening the bowl screws is that over the years it tends to pull the corners of the main body out and slightly warp the sealing surface, and will sometimes warp the meter block.

To save some of the rare carbs, I've had to machine the main bodies, and I have a fixture I use to straighten the meter blocks.

[Chief of the 60's]

Originally Posted by Lemans64

I did use a 1/2 breaker bar to put this together. has been over a year since I have even touched the carb. Helicoil kit is ordered and will attempt repair tomorrow night. Anybody else seen this? Or am I just lucky and I am the only one? :no idea:

This is a joke right?

[Lemans64]

Yes that was a bit of silly Humour. 1/4 nut driver is what I have used. No rachet. just snug. Did manage to install 2 helicoils in the offended holes, all went well.
Bought a kit so have a few more inserts for later use. LOL. I hope not. Thanks for all the input.

[66bonne]

I recently had a fuel leak which appeared to be from one of the bowl bolts. Turned out that the fuel horn to bowl metal gasket was cocked just enough to cause the leak that ran along the bottom of the bowl.
Hope your problem is easily fixable. BTW: I've had to put in a few Helicoils as well.

Jim

[Tom Vaught]

Originally Posted by 66bonne

Turned out that the fuel horn to bowl metal gasket was cocked just enough to cause the leak that ran along the bottom of the bowl. Jim

??? Holley carbs use fiber coated gaskets on the bowls. Fuel Horn? Been in the Holley game for 50 years and do not have a clue what part you are talking about. Got a picture or two?

Thanks

Tom V.

[Lemans64]

Fire it up today with no fuel leaks so all is good, Heli coiled all 4 bolt holes on the front side. have spare inserts for rear if I have to
do it as well. Was no big deal to do but was just a scary thought upfront. Loctited inserts into housing so should be good now
to 100 ftlbs, LOL.