I don't see how this could have been a timing issue between the crank and the balance shaft......as the timing can only change if the case had been split and the crank or balance shaft was removed and not installed correctly.  The cases don't have to be split to change a cam timing chain and guides........find out if the shop split the case for some reason.

 

Im mostly on Daves side.. at least 99,99% the rest goes to aliens or some fabikation faliurs!

And I dont belive in Aliens.. but in any case, they have to ruin the bearings or crack the shaft befor it hit the case!
If the shaft is okey, then it is the bearings!

BlakeEM wrote on 06/28/20 at 14:58:18:


There are 2 things that need timed in this engine.

The camshaft needs to be timed when you replace anything related to the camshaft or cam chain.  This would have been done when they replaced the cam chain and guides......you said the engine has compression and turns over fine - so I believe the cam timing is likely fine as it ran for a year after they worked on it.

The balance shaft needs to be timed if the center case was split and the balance shaft and/or crankshaft was removed.  There is no reason for the shop to have split the center case into the left and right halves to replace the cam chain or chain guides.

Something went wrong, and at this point I don't believe it was the shop screwing up the timing......if they did I can't see why it would have taken a year for the collision between the rod and balance shaft.

This photo shows a nice even "squeeze" of sealer oozed out of the crank halves, and I believe this is the original factory applied sealant, as getting the sealer this even by hand would be difficult.
https://imgur.com/K7IIbHg

I asked where you are located so that we might be able to find you the engine or parts near you.  My northern KY location puts me about as far away for shipping zones as we can get.

I removed it and found more issues.

https://imgur.com/VzDZa9o

https://imgur.com/SXPtibU

Wow!!!!  

Blake, I am so glad your wife is OK.  That could have been a really bad event if it had failed on the freeway.

I agree, the only way the rod could have contacted the balancer weight in that particular location (the lower and deeper rub on your photo) would be for it to be out-of-time with the crankshaft.

A bearing failure might have resulted in the upper rub, but the lower (and deeper) rub had to be timing.

This picture shows the con rod approaching the balancer weight.  While the rod is moving toward the weight, the weight is moving away from the rod.  This is the only position where the rod could conceivably line up with the portion of the weight that has the heavy rub.  In this position, there's like over an inch of clearance between the rod & weight.

The crankshaft turns smooth with no free-play and the bearings aren't making any sound like I'd expect if they were bad. I'll check them more closely once I get the crankshaft out.

If the crankshaft was only contacting the balancer why isn't the balancer discolored from heat like the crankshaft?

Could an over tightened primary drive gear cause this and shift the crankshaft to the side so that it skips gears causing the balancer timing to be off?

https://imgur.com/SXPtibU

You guys are awesome, thanks for all the help and pictures! It's taking me a while to disassemble since I need to keep taking breaks to read the Clymer manual so that I know what I'm doing.