I just took the gamble on a 850 Holley on that favorite auction site. The ad said "The chock horn has milled and the choke mounting on the main body has been removed." The body has been sealed with some red epoxy and I'm sure that will work but I don't like the looks of it. Can I remove the epoxy and use JB Weld to get a closer match to the color of the carb body ?
I've tried to JB weld the fuel inlet on an Edelbrock with no luck. I would say it was about as good of a job as any but sure enough, it didn't stop a slow leak. Posted from the TJJ App for iPhone & iPad
Yeah not sure either, everything else looks good on the carb and I know I could always get a different main body too. Just curious about the JB.
Swade, I used JB weld on a motor cycle tank once to get back from the east coast to the west coast. It worked OK but about noon the second day I had to drain the tank and reapply. What I ended up doing was when I shut down for the night I would drain the tank and reapply it, then it had all night to set up and I did it every day. I aaid all that to say this, at least when I tried it several years back it did not hild up well to the gasoline. I don't know if they have changed the composition in the last 20 or 30 years or not. I do know that there are several types of JB weld if you look, for aluminum for steel and the everyday JB weld. Maybe the type that you use makes a difference. If the epoxy is holding why don't you just try a dab if aluminum paint over it? That way you have not invested much to see if it is going to hold at all. I don't believe that the JB weld will work for you. Something else that you may try is to solder it, they make flux and solder just for aluminum, you should be able to find it at refrigeration supply house, may even find it at a hobby supply or a well stocks hardware store.
Phil you can use JB in that area it'll work fine..... Even better ,find some Devcon. Call me if you can't ....
I used it on a cracked float bowl on an old shovelhead carb it never leaked a drop.Did it as a temp fix ended up selling bike saw buyer 2 years later same carb no problems and yes I told him about repair at time of sale he said he would replace float bowl but never did.
They make a 2 part epoxy for patching gas tanks, Sorry can't remember who THEY is, might be a devcon type stuff, Tim Jones
Every QJ that comes apart gets some JB Weld on the well plugs during the rebuild. First scuff the clean surface with rough emory cloth and let the JB sit and dry for 24 hrs. No problems and no leaking well plugs.
Tony I just did a quick search on the Devcon, they have a lot of applications there. Would this be for metal repair or the gasket, I know it's not the concrete floor repair one ha ha
JB makes a "marine" type that's supposed to be more fuel resistant. I used some on a chainsaw a couple of months ago, and it's still not leaking. FWIW
I would use the gas tank repair stuff. Never had good luck with JB weld. Or maybe go to a swap meet and find the guy selling those fancy welding rods that can weld anything take your carb and let him show you how it works.
been using jb on carbs for 20 years, no problems yet. Mostly on Q-jet well plugs, also to repair craks and plug holes.
How big is the boo-boo? I've sealed holes in 94 tops with aluminum screws. Drill out, tap, thread in screw (with Permatex 80062 on threads), and file down. Onced chromated, it looks good. May have to use a couple of screws.
JB will work, just follow instructions(clean, dry,let set 24 hours).Been doing it for years with NO problems.
No idea, just got the carb and didn't remove the epoxy yet. Took the bowls and metering plates off to make sure everything was there and everything else looks good. I ran a few numbers off the throttle plate and metering blocks and also mic'd the throttle blade area to make sure it was an 850. Everything looks good, right jets, right shooters, base is flat and everything works as it should, just don't like the red epoxy ha ha
i've used it to repair carbs also rebuilt a base that broke when the guy dropped the bike and ripped the water pump off has to be clean and wait for it to dry
from the JB Weld website; Is J-B Weld resistant to water and/or gasoline? When fully cured, J-B Weld is completely resistant to water, gasoline, and about every other petroleum product or automotive chemical. For wet-surface or submerged water or gasoline repairs, try our SteelStik or WaterWeld.
The repair on the Q-Jet well plugs is different from repairing a carb body. The epoxy on the well plugs is to keep the well plugs in place so the well plugs seal, not for the epoxy to do the sealing. A few years ago, we tested all of the various epoxys including J.B. Weld which were sold locally by mixing according to instructions, making a repair on a small part, and placing the item in some fuel in a sealed baby food jar. 3 months later we removed all of the test items; ALL including the J.B. Weld had failed. Do your own tests if you wish. I have scrapped carburetors which were MUCH more valuable than that Holley 850 because I have yet to find a suitable LASTING repair to zinc alloy, and that includes the special rods. Possibly a new formula is now being used for the epoxy, I don't know. If anyone really feels that the epoxy will fix this stuff, I have a number of early Packard, Pierce, Cadillac, Lincoln, etc. carbs with cracks that I will be delighted to sell you for 10 cents on the dollar. Just let me know. Jon.
Devcon is the stuff, theres about a pound of it in the intake runners, plenum, and ports of my FE. Been there for a long time.
I JB welded the 2 barrel carb on a 60 Impala parts car I bought. It worked and I ran the car but I sold the motor off and the new guy is putting a 4 barrel on it so I don't know how long it would have worked.
My son is a CNC machinist in San Jose. He gave me a small amount of Devcon that they use on castings that have flaws, then they machine it! I've used it on cast aluminum, steel, cast iron...(old classic car stuff) It is excellent. The name is 'Aluminum Putty (F)' and the part# is 10610. If you guys can find some of this, you'll love it. It's made with sintered aluminum...
I've repaired two Holley carb float bowls with JB with no problems. The leak was on the top where it's swedged over after machining. I believe there is an "O" ring in there under the metal plug which will deteriorate and leak after a extended bath in carb cleaner (not advised)however done anyway. Still not leaking after several years.
Why not just leave the epoxy & skim some J-B over it. More than likely the aircleaner is gonna cover it up anyway.
B-O-B>>> Why not just leave the epoxy & skim some J-B over it. More than likely the aircleaner is gonna cover it up anyway. >>> Best suggestion yet IMO. The red stuff on there now looks like the old Gasoila varnish-based sealant. Good for gasahol, oil, etc. Jack E/NJ
Guess I got lucky with JB Weld. I had a Q-Jet that the inlet seat threads were stripped. I used JB Weld to glue it in place and it ran for several years with no issues. I believe I still have that carb among my cores.
As stated earlier in this thread, proper prep work and curing is a must. I've never had an issue, even with today's formula.
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