I need to replace my rear axle bearings. first of all, the kit comes with 2 bearings, but looking at the schematic diagram, there appear to be more bearings (perhaps inside the final drive case). the "final drive case" is the same as the rear diff (to me). I know it's not technically a diff. ANYWAYS...

I removed my entire rear final drive case (sealed), with the axle still in there. the pinion gear meshes with the axle and turns it. Can i remove the axle with the pinion gear still attached inside? Can I just bang it out, or will that wreck something?

The final drive case mounts to the shaft drive housing with NO gasket, but a silicone type gasket material. And it's on there pretty thick from the factory. I have about 2500 miles on mine, and have been in an average amount of water and mud. that shaft drive housing and the final drive case are sure full of crud. not a very good factory seal. should I use liquid gasket? the manual says something like "Quick Gasket".

Has anyone taken apart their final drive and replaced the bearings inside? considering all the crud that was around, I just wondered if the bearing inside the case needs replacing/service?

 

You have 2 bearings, 1 on each side. The parts in your schematic may look like mulitple bearings, but you are probaly looking at the circlip on the left hand side of the quad, so it goes from outside in(left side)...Wheel hub, small o-ring, oil seal, circlip, then bearing. On the right side I believe its Wheel hub, dust seal, oil seal, then bearing.
To remove the axle you will have to remove everything on the left side, then take a deep socket to fit over the wheel hub threads and hit it hard, the axle should seperate from the gear case.
As for sealing the gearcase to the swingarm, there should be an o-ring that is between the case and swingarm, as well as use some type of sealant, anything automotive as long as its waterproof.
Hope this helps.

 

thanks atvman. there is no o-ring in the schematic diagram, or that I noticed, between the drive-shaft housing part of the swingarm and the gear case. BUT, when you pull the gear case off, it is quite well sealed, and they show a seal and o-ring. in order to get at those, I'd have to get a specialty tool (almost like a 4WD hub-nut tool) to remove the bearing retainer.

the yamaha repair manual says to use " Sealant (QUICK GASKET) Yamaha bond #1215".

I agree with you tho, there should be an o-ring or better system of sealing because this seal is awful as evidenced by all the crud that has worked it's way in there.

 

The o-ring that I was talking about should be on the left side of the gearcase where the axle goes through, not the driveshaft side. If you look on the left case side is there an o-ring groove?

 

okay, i see what you mean. Yes, there is a small o-ring there. seems to be in the left hub.

FOR OTHERS: you do NOT need to remove the driveshaft to remove the axle. you can bang it out (with a socket to protect axle). I'd recommend removing ALL the right side gear case cover bolts first, THEN remove axle. this will make it easier for you to remove the gearcase cover, as its got a tight seal from the large o-ring that seals it. ALSO, the dust seal on the axle makes it hard to slide the cover over it. ALSO, you need to take this cover off to re&re the bearing, as the bearing sits in this half of the cover.

I completely removed the left side axle housing aswell, as it made it easier to pound out the bearing. There is a snap-ring (or circlip) that you must remove first, before removing the left side bearing. I also removed my rear diff (final drive) and cleaned it out. I see now that this was not necessary. HORRIBLE instructions from a Yamaha Factory manual on how to change the axle bearings (essentially no instructions, you bounce around several different sections to piece it together and figure it out yourself). WAY TO GO Yamaha; you sell a manual that doesn't help.

When i removed the gearcase from the swingarm(driveshaft housing), I couldn't believe how much crap had got in there. there is no gasket there; you make your own out of "quick gasket". I used rtv blue silicone gasket material.

BEARING NUMBERS: the left side is a 6006LU. the right side seemed to say either DG (or 06)4070A. the Pivot works bearing for the right side had 03600.

 

Glad you got it figured out.