Hi all,
I just purchased a 1995 Xplorer 400 4x4 which is my first liquid cooled Polaris ATV. After bringing it home I discovered that there was no oil in the counter balance. In fact there was no CB drain plug. Unfortunately, this is the first time I had even heard about counter balance oil because my Trail Boss 250 and 300 do not have it.

I don't know how long it was driven without a CB plug or CB oil. This ATV only has 755 original miles. But I don't know how quickly the CB is ruined without oil. Probably in minutes I am guessing.

So I added oil (10w30) ran it a bit in neutral and drained the oil. Did this two more times until the oil came out clear. Then added 4.5 ounces of synthetic 10w30 oil.

But the engine still shakes a lot at idle and has a knock even with the counter balance oil added. I have a feeling that the Counter Balance is toast and am looking for suggestions and ideas on what to look for and how to fix.

It would also be good to know what happens if you just keep driving it with a tore up counter balance?

Your input is greatly appreciated.

Thanks all!

 

Vibrating is probably caused by the counter balancer bearing worn out from lack of lube. It's either repair it now or face possible case damage if it goes too far. You need the tool to pull the balancer,they have them here but not cheap.Counter Balancer Puller There are places online that repair counter balancers and can replace the bearing.Here's one down in my neck of the woods that's been working on Polaris engine for years.Polaris 350L 400 Counterbalance Service w P Bearing and Seals Included | eBay Again best not to wait on this as I've seen them come in all rusted up,some that have cases broken.

 

Hi OPT,
I really appreciate your insight. Looks like I have a lot of work in front of me.

Is it worth it to pull the motor can you get to the counterbalance pretty easily while it is in the ATV?

Can you recommend any videos, threads, or how to descriptions on removing the CB?

Thanks

 

You can do it in the frame,but the hard part is that the outer case coolant inlet tube hits the frame. You have to end up removing the top motor mount and sometimes the front one to get enough room for it to clear. Just about as easy to go ahead and pull the engine. The best guide around is the manual as it has step by step guides with pics to help tear it apart and reassemble.Plus good pics on the water pump seals and bearing and how they're supposed to be installed.This most videos wont even show.https://www.tradebit.com/filedetail....air-manual-all

 

Thanks again OPT! I checked out the manual and the disassembly detail and photos look pretty good.

I am going to have to set this aside for a bit while I finish other projects but I'll be back online if I have any issues.

Thanks!

 

Hi again OPT,
Another question. If the atv has been run without CB oil, would the water pump and bearings be shot too?

I'm trying to figure out how much needs to be rebuilt and what gaskets, seals, and bearings I should also be purchasing.

Thanks

 

You have to remove the water pump housing to get to the c/b,so seals and bearing change are necessary. You need the two water pump seals(pay close attention on assembly because both seals are different) a new w/p bearing,water pump gasket,and outer case gasket. You can price them individually through here.Dirt Cheap Yamaha, Polaris, Suzuki & Kawasaki OEM Parts & Accessories – Cycle Parts Warehouse Or places like Partzilla,Cheap Cycle Parts OR complete gasket kit,seals and bearing are on ebay.Polaris Water Pump Bearing Seal Gasket Rebuild Kit All 350 400 2 Stroke 90 2003 | eBay

 

Thanks again OPT.

Sorry for all the questions but...

Should I replace the crank bearings too?
How would I know the crank bearings need to be replaced?
What would you do in this situation if it was your atv?

I'm not trying to make more work for myself but if I am going to have the engine out on a bench I might as well take care of as much as I can. My only concern is that crank bearings seem like a whole new level to replace compared to the counter balance and water pump.

 

You can pretty well tell on crank bearings by slowly rotating the rod around. Grab the connecting rod close to the crank and pull up and down. If there is ANY up and down play(side to side is usually ok) then you'd have to install a rod kit. By that time you're at the crank bearings and seals also. Just put it this way,I wouldn't guarantee just a top end on any 2 stroke that came into the shop no matter how good the rod and bearings may feel simply for the fact that I had a couple come back and bite me. If the lower rod bearing spits pieces out,a new expensive top end can be destroyed. Plus on cylinders I bored for carry out I warned people what could happen.. It's just a chance you take on a two stroke.

 

You're the best OPT. I'll check things out as you suggest and then decide how much risk I want to take.

This could be a long journey for me. So i am going to take care of a few other projects, garage remodel, lawn tractor, tiller, etc. before I start. But then, I am clearing off a bench for the 400 rebuild.

Thank you so much.