Just purchased a 1993 350L, with known counterbalance issues. First thing I did was remove the crankcase drain plug and only a few drops of oil came out, then pulled cb plug and totally full of coolant and no oil. I stripped the side case down to cb, bearing on shaft was bad of course and seal looked bad too. I have two questions though. 1. The threaded end where impeller mount to stripped only the nut on removal and not shaft, also cb shaft itself looks okay. 2. The cb assembly has a little play in it, maybe less than 1/16 of and inch is that acceptable? Do I need the whole unit or just bearing and seal?

 

Welcome to the forum! If you can rethread the shaft threads and if the bearing doesn't feel like it's extremely worn,then you might be able to save the counter balancer. Best to let a good machine shop do this. "IF" the bearing behind the counter balancer gear is worn out, it is not listed on Polaris replaceable parts,but I know people have replaced them. I never had the time to do this at the shop. You have to mark the balancer gear and sprocket to realign precisely and using a press and heat carefully press the shaft away from the gear and then the bearing can be removed. If you have a local bearing house you can match this bearing up.Some people have come into the shop and just ordered a new counter balancer if they bent the shaft. Others had machine shops do this and were able to save the counter balancer. Plus if the shaft where the seals ride is really corroded up to where you can't use emory cloth to at least try to clean it up to where new seals wouldn't leak again,then you would have to have this area built up and machined back down.(some I've heard have even used clear epoxy and then smoothed down) Cost could get pretty high,but a new counter balancer is close to $500 now and might be worth the effort! 350 and 400 2 stroke engines were good engines,but can be very expensive to rebuild depending on the damage. Used balancers are on Ebay,etc,but probably in the same shape as the one you have and would usually have to have the main bearing replaced anyway. OPT

 

Thanks for the info. I'll give it a try. Should there be any play at all in the shaft while still installed? My biggest concern is the impeller nut threads. This this only has 3k miles on it so I think whatever needs to be done is probably worth the effort. Thanks again

 

Shouldn't be very much play when installed,so make sure the c/b bearing is in good shape.This is the problem with most of them that have a lot of time on them or damage from the coolant. Plus you need to check the very bottom bearing in the case for the counter balancer shaft (if you have the c/b out of the case) and just turn it around to make sure it's ok. Good luck. OPT

 

I emery clothed the shaft and looks great, found all outer bearings and seals at a bearing house. Just need to check bearing behind shaft and should be all set. Thanks again

 

Polaris 350L. Should the water pump bearing fit tight over shaft ? Mine will slide on and off easily

 

Water pump bearing should be a snug fit in the water pump casing and should be fairly easy to slide the casing assembly over the shaft. More important is that the seals should be snug against the shaft and that you have them installed properly. The two seals are different and install a certain way. Best to have a reference or a manual if you don't have one. OPT

 

I really appreciate all the advise. I did download a manual for it, and directions aren't super clear. Anyway I emery clothed the shaft and is pretty smooth except for one small spot that I think I can fill with quick steel. The bearing is not super snug but don't need to pound it on either.

 

Look inside the small water pump housing and you will see a small hole that goes through the housing where the bearing and seals ride. Don't cover this hole up with the inner seal or bearing. Sounds like the shaft will be okay from your description.. OPT

 

Yeah the service manual must require a masters degree in engineering or something cuz it isn't very clear. But if I remember right how they came out , the were both back to back with the open side facing out and just far enough apart not to cover the hole.