Topic: Cracked Case

[sdefoor]

I was starting a project bike I purchased a couple months ago and found bits of metal in the oil filter. So I started a teardown and inspection of each part. All parts up until this point look perfect. Although this past weekend I found the culprit. The ol cracked case b/c of the chain. My question is, I have been researching the Alumiweld product and think this may be the way to go but I was wondering what you all thought would be the best course of action. I have a couple things going through my head like if I use the alumiweld and it doesn't hold I may can still get it TIG welded. and if neither of those work I would have to get a new case anyway, so in my opinion its better to start with the cheaper fix (alumiweld) and work toward the most expensive (buying a new engine case) Here are some pics of the damage

[CycleRanger]

That's one of the better chain-damaged cases I've seen.
imho, I would tear it down, have the case vapor-blasted and get it professionally welded up.
You'll probably have to heli-coil that bolt hole as well.
More expensive than epoxy but better and probably cheaper than new cases.

[sdefoor]

Better as in more damage or better as in should be easier to fix?

[CycleRanger]

Better as in more damage or better as in should be easier to fix?

Better as in easier to fix. All the pieces are still there.

[calj737]

You won't fix that case with "alumiweld" rods. They are a brazing rod, not a welding rod. Where the PO jammed all that blue RTV goo, that has to be removed and the case pulled together, then welded for any strength to exist. The hole should be drilled, filled (peen as you go), then re-tapped for proper strength. A helicoil will not work until the case is restored structurally.

Because the case is cracked and in tact, welding from the inside carefully will work just fine. Watch the heat so you don't get casting bubbles and observe any internal clearance areas closely.

[sdefoor]

My plan originally was to pull it together and grind a small groove for the material to bond in. But now I may just clean the case and take it to someone who knows what they are doing with a TIG.

And yeah I had no clue what was going on until I got to cleaning and saw the blue color. It was caked from the top of the bottom half all the way under the sprocket. I immediately knew what was going on and it made me sick. lol