Crack in engine body (non-pressure part), recommend some hack/solution

[AndyAndyAndy]

Engine runs great, but has a crack that leaks like crazy. If not fixed, I will just scrap it. So any solution would do at this point -it can't be broken any further.

I have only regular MIG/STICK welder for steel.

Could it be repaired? Or could I somehow hack my MIG a turn it into aluminium TIG or something? I don't thing JB weld cut it here?

 

[mckutzy]

Believe it or not... JB weld might be your ticket...

Clean it extremely well.. gouge out the crack a bit... Might take a full tube of stuff... I reckon it'll fix it enough.....

It's a China motor... So might after that... Just get a new one...

 

[snowjob]

Whether JB Weld or Aluminum rods with a torch, you should be able to fix it. Since it is not structural, I too would start with JB Weld. I used the rod/torch method for some Bultaco cases, but I wanted them to look original when I was done. It definitely took some practice to get the technique and even then it is finicky.

 

[madprofessor]

The correct version of JB Weld worked on my cracked Predator. Used a couple of little Dremel grinding stones to smooth the area where a little jagged spot about 1/2" long appeared on top of case, in a valley about 2" x 2.5" ? as I recall.
Thing is, I roughed up the surface of that whole valley, and covered the entire surface with JB Weld as the raised perimeter kept it from oozing away. Haven't even thought about it since.
Only laid a 1/8" max coat on it, gave it about 3-4 days to cure indoors. That's the key, thin coat, long cure, repeat if desired.

 

[AndyAndyAndy]

Original JB weld is available over here. But costs more than running second hands engines on Facebook marketplace.

So I sanded it, cleaned it with 100% acetone and put over it some local $4 epoxy. We will see.

 

[ezcome-ezgo]

It's on TV so it must be good.

 

[madprofessor]

Alteco says it works for metal, doesn't shrink, and is oil resistant. Only other thing I was looking for was heat resistance, no claim about it.
If it's that similar to JB Weld, it'll probably work the same. I still stand by allowing for excessive curing time before testing.

 

[AndyAndyAndy]

I put engine back on the bike and so far it is holding up OK, no leaks. Somehow I'm still not convinced that this is a way to go. It just doesn't seem that this bond will be enough to withstand all the shaking, temperature changes... . I still think, that it should be welded for real, not just slap a sticker over it.

 

[SCcrashinv]

I used JB weld on a diesel tractor engine once. It held and is still holding after several years. I don’t think you can get more vibration than a diesel. As the other guy said clean and dry.