Oh, my cracking block!

[Fouled Plug]

Actually, it belongs to my brudder-in-law. Yamaha 90 has a crack in the block behind powerpack that weeps water. He currently has applied the finest product JB Weld makes, and it's holding for now (I know! I know!) Can it be sucessfully welded? What method would be applicable to a powerhead, MIG welding? I don't know exactly what alloy is used. It's too nice of a motor to toss, and he won't get a new block or rebuilt powehead despite my advice. Can it be done? Thanks!

 

[12Footer]

Re: Oh, my cracking block!

Yes, it can be welded 99% of the time. The other 1% would be because it is in a bad spot. Any good welding shop could do the job for him.<br />And it doesn't matter what alloy it is,provided it ain't cast iron (which would be strange)...And even then, there are some really great welders who whould be able to.

 

[Walter]

Re: Oh, my cracking block!

As lightweight as those engines are...I also doubt the block is cast iron. But even if it was I agree that it could be welded. Problem is, it would have to be pre-heated first... which means the engine would be torn down to the block. Heck...after going through that much trouble, I'd just buy a new/used block.<br /><br />Walt

 

[PaulW]

Re: Oh, my cracking block!

If it is an alloy, there is a product in the UK called Lumiweld. I've used it to repair broken aluminium crankcase and gearbox castings and it is magic stuff. <br /><br />It is not a true weld, I suppose strictly it should be called aluminium brazing, 'cos you don't quite get the alloy up to melting point. <br /><br />If you can cet hold of it, I'd be fairly confident that it will do the repair. I recently used it to patch a hole in a very awkward part of a friends motorbike gearbox casing, by using fire cement to support it while it flowed across the gap.<br /><br />PaulW