Carburetor Passageway Plugs

[ventura ace]

Here's a picture of a carburetor passageway plug that wiggled its way out of the front carb (40 IDF's) on my drive to work this past Wednesday morning:


Does anyone know the proper accepted practice for putting these back in, so that they will seal off properly and stay in place? It's a lead plug with a shoulder as shown in the picture. I'm thinking that some sort of sealing Loctite might be suitable to coat the surfaces before install, then wack it home and wack it some more to make it spread out and seal, then cover the exposed end with a light layer of JB Weld. Any other suggestions?

You can imagine that it was a harrowing experience having the plug pop out while driving. It dumped about 2 gallons of fuel all over the intake manifold and engine parts below within about 2 miles of driving. I pulled into a gas station about 20 miles from home, not yet knowing the problem, but I did know that the engine was idling awfully rough, and the fuel gauge had dropped quite rapidly. I popped open the hood, saw the pool of fuel on the waffle intake manifold, and the steady stream of fuel pouring out the lower back side of the fuel bowl. I noticed that I was standing in a pool of gasoline on the pavement by now, and jumped to shut the engine off ASAP. I guess I'm really fortunate that it didn't ignite.

I had it towed home. After pulling the carburetor, I found the lead plug had lodged in a crevice between the cam tower and the intake manifold, thank goodness. I'm thinking about covering all the passage plugs with a light layer of JB Weld. A fuel leak like that could be quite a disaster!

Alvon

[gary124sport]

I would imagine at one time, like when it was originally manufactured, those plugs were pressed in. With age and several thousand thermal cycles and a few soaks in solvent and such the press fit loosened up a tad. I don't know what epoxy or loctite is solvent and temperature proof. If you are able to source a product such as that then I would coat the mating surfaces and cure IAW manufacturers instructions. Otherwise have a new plug machined for a press fit again or tap some threads into the carb and plug with a suitable mating fastener.

[fiatfactory]

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[mdrburchette]

I'll be checking all of my IDFs to make sure I have no seepage around those plugs. Thank God nothing major happened to you Alvon!

[baltobernie]

WOW!

[majicwrench]

I would be tempted to tap it and put a threaded plug in.

[ventura ace]

Thanks for all the inputs. Looks like there are a few options, all of which end with "coat with a light layer of JB Weld".

Alvon

[sptcoupe]

I have had to replace these seals a few times and have just tapped them out and screwed in a brass screw with a flat washer similar to other brass fitting on the carbs. I may have an extra one of these screws at the house in Dallas, but I am not there. I have never had a problem with the fix. Do not use teflon tape or other sealants on the threads, as it will eventually work it's way into your fuel system and can become a real pain.

I have never had one blow out, but caught it when I saw the gas stain around them and noted there was a bit of gas leaking. The first time I figured out that it was the plug leaking, I was trying to chase down a "raw gas" smell that I knew was a gas leak somewhere that I couldn't find. The plugs were the last place I checked, but now are the first place I go to when I smell raw gas.

You were lucky! That was a lot of gas!