JB Weld repair??

Will JB Weld work to plug the pin hole in an exhaust manifold? Any suggestions for doing it?

I know that welding/brasing would work better but he doesn't want to take it off the tractor and neither he nor I weld.

Let me know your thoughts.

I bought some Hi-temp epoxy from JCWhitney. Haven't tried it yet, but it is supposed to be able to withstand the high exhaust temps.

Two different things you might try....

I used to work in an automotive repair shop 24 years ago.... we had a way to seal cracks in cylinder heads. We had some tapered taps and cast-iron plugs. We would drill the crack, tap it, and insert a cast iron plug {screw in} with a thin coating of a resin sealer (valve seat glue). Then after the resin glue set, we would grind off the plug flush with the head. I do not know if these tapered cast plugs are even available anymore... but an old automotive machine shop might help you out!

Second option... The "old timers" used to fix pin holes and such in the big old cast-iron kettles with a piece of pure copper! I have done this and it really works!!! I had an old cast iron kettle that had several pin holes in it. I took a piece of heavy copper wire and {basically} riveted the copper into the hole {after cleaning all debris/rust out of the hole}. Just be careful that the hammer {and it does not take a Big Hammer either} hits the copper only... and not any part of the casting. The copper is mallable enough to fill the odd shape of the pinhole as it swedges out. This method seals the pinhole real well and the heat will not melt the copper... also after a while the copper discolors and you can't detect the difference in color.

Sounds like you and I do the same type of repairs.
The square rod is cast iron in stick form and needs the flux to flow , for manifolds it is the
only way to do a good job. Fusible spray powder
also works and I use it on many things , but the
square rod works best for manifolds. I went to welding supply
today and got 50 pounds of square cast rod .

george

Would you happen to have the manufacturer's identification for that square rod (plus the proper flux)? I'd like to try some if I can find it.

Thanks,
Rod

I talked to tech department at harris today and they admit that the Kastweld 111 or alloy cast weld is nonmachineable and they don't have any that is machineable . After many hours on the phone today , I found a supplier in texas that says his is machineable , have a box on the way. They are a valve seat supplier for the automotive trade and also have the cast rod poured by a local foundry to their specs so that is is machineable . It's made for the repair of cyl heads that are cracked or otherwise damaged and has to be able to be machined to install valve seats .

george

For more than 20 years I used Airco rod and flux but since airco is no more , that part was bought by lincoln and they dropped that product. I bought a 50 lb box of kast weld 111 last year , it welds fine but the only conditionaly machinable , very hard to drill , and near impossible to tap . I talked to factory 2 weeks ago , they sent another box to the distributer last week , I got it thursday , tried it last nite, same thing . new name on the box is alloy cast weld . have to call factory on monday as this doesn't work for at least half of the repairs I do. For welding any thing that doesn't need drilling and tapping this rod works well . Flux is harris/welco # 800 .Rod is from JW harris . Send me an email and I'll let you know what else happens .

george

I am not familiar with Liquid Steel. I take it is better than JB.

You may try drilling a hole in manifold while it is running, tap the hole with a thread that you can match with a nice bolt.
We do this on our New Duramax diesels to place an Exhaust Gas Temperature guage.

Worth a shot.

Mark