What balance shaft do?
The engine is vibrating and the balance shaft is reduced vibration, shafts rotate in the opposing direction to each other at twice the engine speed and have timing marks as well, and the shaft is eccentrically weighted. That model 2 shaft has in 1 unit and is located under the crankshaft.
If the balance shaft is failing probably you can notice a rattle or knocking noise on idle these are the first symptoms, after driving for a long period that a possible loss of oil pressure and the broken gears make more damage like a snap chain.
Replace or delete?
Yes, both are working but the difference is the price of replacing the cost is huge and the problem is still coming back later the miles are so much better to remove the balance shaft unit if no more damage, so before need to look around properly. I have done this a lot of years back without any problem some vehicles run over 100,000 miles.
How to remove and what to check.
First, drain the engine oil and remove the oil filter, after that remove the sump and we can see this beautiful balance shaft unit.
Number 1 is the balance shaft unit just unbolt the 4 outler bolts but be careful because is full of oil.
Number 2 you can see how wear and tear just remove with the 2 bolts.
Number 3 is important you can see the gear teeth just turn around the engine by hand and check the teeth for any damage, personally I use brake cleaner to clean down the oil better to see if no any damage is a happy day, just let like this and put back the sump, if you see damage need to remove the side cover what is not a really great job. What I see the worst damage here in the picture:
So if you need to remove the gear cover because the gears are damaged you need to block the oil line for that you can see in the picture marked with a red circle clean out the hole and put the lock tide I’m using 6mm copper washer as well on the bolt:
and 1 more oil feed hole needs to block for the balance shaft unit
When you put back the side cover and the sump just choose the proper sealant /liquid gasket / otherwise, the engine oil just keeps leaking normally I’m just let to dry minimum 12 hours before filling up with new engine oil.
Recommended liquid sealant is MMC part number MZ320771 is come from Threebond 1207F.