'98 Xl 760 engine swap

[Bailey]

First post.....y'all be gentle
I'm in process of swapping out my engine with a new SBT. My first of probably many questions is; Is the coupling on the crank shaft left hand threads? I'm having some difficulty removing it and thought I should ask before I destroy something.

Thanks, Bailey

[Technical Support]

Re: '98 Xl 760 engine swap

Bailey, they spin off counter clock wise, Try not to break the fingers on it, if you cant get it off we can supply you with a salvage one for $25.00 Tom SBT tech.

[Bailey]

Re: '98 Xl 760 engine swap

Thanks, Got it off with no damage.
My next burning question is: What could have happened?

First off, I'm no stranger to wrenches, been getting greasy on something for over 30 years. I understand the concept of a two cycle but this is my first intimate encounter with one of these creatures.

Here's what happened. At or near WOT, the rear rod seized on the crank and snapped just above the crank journal. Amazingly, there was no damage to the block, just a broken rod and a really ugly crank journal. While tearing the engine down for inspection, I noticed that there was a good bit of oil inside the block but the broken parts had turned somewhat blue. This indicates to me a lack of lubrication. Should I look at a faulty oil pump or could this be a carburator issue? The carbs were rebuilt two years ago (not by me) and the engine had been running flawlessly.
I certainly don't want to cause damage the new engine so I am looking for probable causes for failure. Any suggestions would be greatly appreciated.
BTW, I plan on running premix in the new engine.

Thanks, Bailey

[Bailey]

Re: '98 Xl 760 engine swap

bump for tech support