I do t recall this much wobble when it was running in Oct. Same crank, same pulley.

 

Yes, they go bad. They are two hunks of metal with a rubber isolation surface bonding them together. I don't have any experience with Rover balancers but catastrophic failure can be an engine killer in BMWs. That said, it looks like the crank bolt is also spinning out of round, not just the balancer. Play the video in slow mo and it's a little easier to see it. To me this says yours seems pretty far gone and the whole shaft is now wobbling.

Either that or it's just loose and you happened to catch it in time???

 

She’s tight - for sure. I noticed the bolt wobbling too which leads my racing mind to think the crank may be bent - I always seem to go worst case…

 

Unlikely the crank's bent, just being dragged out of round by the imbalance. Possibly wrecking the seal however.

 

Yep. New balancer and seal(s) in bound.

 

I really hope it’s not bent. Again, the only reason I went there is because the bolt is wobbling too.

 

Machine a new keyway and install the balancer upside down for a few thousand miles to "unbend" it.

 

I thought you were serious for a second 🤣

 

Ordered last week from Rimmer Bros - BUCK$!!!

She goes in with a new seal tomorrow.

Started the engine for a moment without the wobbly balancer to look at the crank - rock steady!

 

With the old one removed can you see what failed?