Engine case broke

The bike is a 1984 ZN1100.

When installing the crankcase breather cover I over tightened the bolt and the engine case broke. I attached a pic of the broken piece

Can I just have the piece welded back in or do I need to get a new engine case?

It goes without saying that I'm an idiot.

Pic?

It can be welded. You may want to invest in a torque wrench calibrated in inch pounds; it can save you headaches. Ed

I have one of those but in my infite wisdom I decided to use my meticulously calibrated arm.

But in stripping it down to get the engine out I found what may be one of my problems. There was no exhaust clamp on one of the pipes coming out of the head where it meets the rest of the exhaust.

How much metal is let where that broke? Can it be drilled deeper? Pictures always help. I suppose it would go through to the transmission if drilled to much. Since it's only the breather, it wouldn't take much to hold it, hence one center bolt. If there is any metal deeper, you might be able to first drill the hole, then glue with JB Weld the broken piece. Then Tap from the existing threads down into the new deeper hole? Just a thought.

It most certainly can be repaired. But it will likely require a complete engine teardown to weld it. At least with the older KZs, you cannot replace just the top 1/2 of the engine cases. When the cases were made, they were assembled, then machined for the crank and other internals as a unit.

Looks like you are looking at an engine rebuild, or find another engine. Sorry for your misfortune. I've done many similar things myself.

Cheers,
Ross

IMHO I would try and JB weld it first, and save pulling the motor. I know it's shady shade-tree mechanics but it's worth a shot.

Could you post a couple of pics of the engine,one from each side.

I did try JB weld and it didn't hold up. I have an evinrude that has jb weld for part of the water pump housing and it's holding up great after 5 years.

I pulled the engine and dropped it off at the shop to be welded. I've been needing to tear into the bike any way and replace the o-rings and seals in the final drive. I kept putting it off but no better time than now I guess. Pulling the engine by yourself is no fun.

I will post pics when I get it back.

Vranasaurus wrote: I did try JB weld and it didn't hold up. I have an evinrude that has jb weld for part of the water pump housing and it's holding up great after 5 years.

I pulled the engine and dropped it off at the shop to be welded. I've been needing to tear into the bike any way and replace the o-rings and seals in the final drive. I kept putting it off but no better time than now I guess. Pulling the engine by yourself is no fun.

I will post pics when I get it back.

Oil will mess with a bunch of stuff....alum is so porous and holds oil deep inside the material.....hard to get a good bond.

As promised, here is a pic of the repair.

fyi its's thanksgiving so I clicked the red thank you on all of the posts, if i got you twice or not at all you can thank me later, goodnight. :evil: