I just serviced my 2000 Kodiak and when I checked the rear dif. it had water in it. This explains the problem I was having with it overflowing out the vent. The flexible boot at the front of the swing arm seems to fit quite lose, so I am thinking this may be the source of the water intrusion. Has anyone else run into this situation before and if so any suggestions for a fix. Thanks

 

I have the same problem with oil coming out the vent but i have not check the diff to see if there was water in in do you think it is coming in from the vent hose at the base

 

The vent for the rear dif. runs up high near the gas tank so I don't think this is how the water is getting in. It would have to be either through the axle seals,wich appear to be dry, or through the front of the dif. on the pinion seal.I plan to pull the boot off at the swing arm to get a look but have not had time.

 

hi there!!! the reason you all have water in your diff is because when you use your quad and run it at high speeds down the trail the diff gets hot, very hot...when the oil in the diff gets hot and then you go through water, the coldness of the water cooling the diff forces the hot oil out through the vent line and sucking in water through the seals. after a period of time all the oil will be replaced by water, and that isn't good for it!! after every weekend's hard ride you should change the oil in the back and front diff... it can't hurt if you change it more often. after all oil is cheap and diff's aren't.
One thing you can do as I did, is to replace all your open bearing in the back with really good sealed bearings. coat them with grease on the outside as extra precaution and put the seals back in, new ones are better, and they are cheap. also, if you wish you can drill and tap a grease nipple in the carrier tube on the right side of the rear diff, preferably on the top or the front side near the diff. after fill as much grease in there as you can and this will help keep the water out...permanently!!
hope this helps and you can do this to any quad, especially Yamahas..

Mike
avid wolveriner

 

I am not saying you are wrong about water being sucked in through the seals,......but if that was the case then why wouldn't oil be coming out of the seals. I re routed the vent lines on the dif. on my wolverine and haven't had any trouble since.
Before I done that I was getting oil in the diff about every ride

 

The theory about water being sucked in through the seals sounds like a stretch to me . If that was the source than the front dif. should have water in it wich it does not.

 

Been there done all of this, this is one of yamahas weak points(exposed alxe)dirt will eatup the seals and let water in as explained in the above post. If you install a grease fitting in the axle tube be careful when greasing, too much grease and you will force the axle seals out,i decided not to do this to mine, i just use a good marine grease and plaster it on everything in sight.