1996 XP 800 severe vibration

[7TCUDA]

Engine or driveline has a vibration that will shake all the bolts out of the exhaust and virtually everything else in under 5 minutes. I have pulled the drive shaft and it rolls true. When I pulled it I noticed that the rubber bumpers at each end are missing, but doubt that would cause so much vibration. The pump spins smoothly without noticeable roughness.
I am currently on vacation in Osoyoos BC with limited tools or parts access. I know that pump alignment can cause vibration too, but am currently lacking a good way to test. All mounts are tight, no engine movement. I believe this extreme shake may have been the cause if the initial mag/flywheel bolt failure [I bought it not running]. The snap ring holding the cover on the back of the counterbalance has broken after my first couple of short test runs, and the cover has disappeared in the hull. Since that has now been exposed to water, I will be yanking the engine and tearing apart the bottom to look for damage there.
Is it possible that the previous owner on a prior rebuild incorrectly installed the balance shaft? It shakes that bad.
Any suggestions on where to look for the shake, would be appreciated.
I have poor internet here so may take a bit for me to respond.

 

[CReynoldsMIZ]

Yes, I would bet that the counter balance shaft was installed incorrectly. You need to rip the engine out.because that shaft was exposed to water and had no oil in it. You will have to split the halves of the crankcase, a manual or becoming a premium member where you have access to them would lead you step by step on what to look for.

 

[7TCUDA]

Well just got around to ripping that engine apart... counterbalance shaft is 90* out of phase - talk about careless assembly. Unfortunately the seals on the CB shaft are in very poor shape so I am going to have to replace/exchange the CB shaft. While I have it apart and waiting for the shaft, I will be drilling and tapping the case for oil drain and fill plugs... similar to my '98 SPX.

 

[SabrToothSqrl]

Who did the engine work?

 

[7TCUDA]

Sorry, no idea. I was not provided receipts for any previous work. I knew it had at least a top end done at one time as the paint was off the head bolts.

 

[DA080682]

Sorry, no idea. I was not provided receipts for any previous work. I knew it had at least a top end done at one time as the paint was off the head bolts.

I wouldn't assume there was top end work done just by missing paint on head bolts, but it's obvious someone messed with the CB shaft and if they couldn't get that right, what else did they mess up?