Chaincase oil seals depth

[MitchRS]

I'm currently in the process of changing the bearings and seals on my chaincase and cannot recall how deep the seals sat. I completely forgot to pay attention to the depth that the original ones were sitting since I just assumed that they bottomed out against a lip of some sort.

Would anyone happen to know if I simply put them all the way down to the bearing or should there be a space between?

Thanks for any tips or help!

 

[Brotherdan]

I'm currently in the process of changing the bearings and seals on my chaincase and cannot recall how deep the seals sat. I completely forgot to pay attention to the depth that the original ones were sitting since I just assumed that they bottomed out against a lip of some sort.

Would anyone happen to know if I simply put them all the way down to the bearing or should there be a space between?

Thanks for any tips or help!

If you look at your shafts you should be able to see witnes marks where the seals & bearings ride& you could measure from here, it’s been a minute since I had any apart but if memory serves me correctly you drive seals in until just flush with housing bore, sometimes you can also see witness marks in the bore where the seal was previously, i can check the manual later if you don’t see the marks im talking about

 

[74Nitro]

I put them in the middle of that shouldered area that holds them, or I'd estimate that to be about 3-4mm back from the bearing.

 

[MitchRS]

If you look at your shafts you should be able to see witnes marks where the seals & bearings ride& you could measure from here, it’s been a minute since I had any apart but if memory serves me correctly you drive seals in until just flush with housing bore, sometimes you can also see witness marks in the bore where the seal was previously, i can check the manual later if you don’t see the marks im talking about

Thanks for the reply, I'll have to take a look when I go back up to the cottage this weekend, there's probably witness marks that I also didn't notice... I'll keep this thread up to date over the weekend.

I put them in the middle of that shouldered area that holds them, or I'd estimate that to be about 3-4mm back from the bearing.

Good to know! Thank you for the insight. I imagine that they don't sit fully against the bearing so that oil can get fully though into the backside of the bearings.

 

[74Nitro]

Thanks for the reply, I'll have to take a look when I go back up to the cottage this weekend, there's probably witness marks that I also didn't notice... I'll keep this thread up to date over the weekend.

Good to know! Thank you for the insight. I imagine that they don't sit fully against the bearing so that oil can get fully though into the backside of the bearings.

On the factory setup, the bottom bearing gets no oil, it just just relies on the grease. The seal would be just in case any oil were to get by the one seal in the bearing and also to keep snow and water out.
The top bearing has no seals so that seal does in fact keep oil in.

 

[MitchRS]

On the factory setup, the bottom bearing gets no oil, it just just relies on the grease. The seal would be just in case any oil were to get by the one seal in the bearing and also to keep snow and water out.
The top bearing has no seals so that seal does in fact keep oil in.

I'm actually surprised that oil doesn't get to all bearings, you would think it would be beneficial.

I also received a bearing that had seals on both sides for the top of the front cover. The bearing I removed only had a seal on one side, so I'm not sure if this is a revision or simply the wrong bearing was placed inside the box.

 

[74Nitro]

I'm actually surprised that oil doesn't get to all bearings, you would think it would be beneficial.

I also received a bearing that had seals on both sides for the top of the front cover. The bearing I removed only had a seal on one side, so I'm not sure if this is a revision or simply the wrong bearing was placed inside the box.

There are a lot of metal filings that come off the teeth of the gears and chain over time that cause the bearings to develop a bit of a growl and roughness. It's debatable which way to go with seal placement.

 

[Nytophazer]

Hey fellas,
Sorry to jump in on this w/an off topic subject here but what are you guys on the xtx's nyro's doing to mount your snow shovels. And how are you "anti thefting" as well. Thanks for the help and info.!
Didn't know how to post this on its own here...

 

[Brotherdan]

I'm actually surprised that oil doesn't get to all bearings, you would think it would be beneficial.

I also received a bearing that had seals on both sides for the top of the front cover. The bearing I removed only had a seal on one side, so I'm not sure if this is a revision or simply the wrong bearing was placed inside the box.

I would say its an aftermarket kit& they sent you a generic bearing, they are almost always either open on both sides or sealed on both sides,simply remove 1 seal with a small pick or flat blade screwdriver, this has been debated at length but im of the thought that when it was engineered they had a reason to seal one side only so I’ve always reinstalled mine that way& have never had any issues

 

[MitchRS]

I would say its an aftermarket kit& they sent you a generic bearing, they are almost always either open on both sides or sealed on both sides,simply remove 1 seal with a small pick or flat blade screwdriver, this has been debated at length but im of the thought that when it was engineered they had a reason to seal one side only so I’ve always reinstalled mine that way& have never had any issues

It's possible but i did order a genuine Yamaha part from a local Yamaha dealer using the parts diagram from my sled.

I'll definitely take a look at removing that bearing seal, i also prefer to have things the same way they came out.

 

[Brotherdan]

It's possible but i did order a genuine Yamaha part from a local Yamaha dealer using the parts diagram from my sled.

I'll definitely take a look at removing that bearing seal, i also prefer to have things the same way they came out.

In the parts diagram I use they are showing the upper chaincase bearing is a fully open 6205 koyo bearing, maybe someone had this apart previously? What brand was the bearing you removed ?yamaha number shows to be#93306-20532-00 should be the same bearing used from 2003-2021 in our applications, im sure it won’t hurt either open or sealed one side

 

[74Nitro]

In the parts diagram I use they are showing the upper chaincase bearing is a fully open 6205 koyo bearing, maybe someone had this apart previously? What brand was the bearing you removed ?yamaha number shows to be#93306-20532-00 should be the same bearing used from 2003-2021 in our applications, im sure it won’t hurt either open or sealed one side

The top inner bearing is a 6206 open, while the top outer(cover) bearing is a 6205.
The lower bearing is 6205.

 

[MitchRS]

In the parts diagram I use they are showing the upper chaincase bearing is a fully open 6205 koyo bearing, maybe someone had this apart previously? What brand was the bearing you removed ?yamaha number shows to be#93306-20532-00 should be the same bearing used from 2003-2021 in our applications, im sure it won’t hurt either open or sealed one side

That is the part I received (93306-20532-00), I'll have to take a look over the weekend at what type of bearing was removed, the one I removed had an open end and one sealed end which faced the back side of the cover.

So I don't know what happened there but the bearing was the same size and went in the case no problem. I'll just remove the seal on it this weekend and I should be good. I'm pretty certain all bearings I received were Koyo bearings.

 

[74Nitro]

That is the part I received (93306-20532-00), I'll have to take a look over the weekend at what type of bearing was removed, the one I removed had an open end and one sealed end which faced the back side of the cover.

So I don't know what happened there but the bearing was the same size and went in the case no problem. I'll just remove the seal on it this weekend and I should be good. I'm pretty certain all bearings I received were Koyo bearings.

Notice how Yamaha codes the '6205' in the middle of their part number.

 

[Brotherdan]

Notice how Yamaha codes the '6205' in the middle of their part number.

Yes I agree but they do have special bearings for snowmobile & atv using the same generic number in there part number so be very careful going by that, the tapered id secondary shaft bearing is a good example where it calls 6205 in yamaha part number but is NOT a standard bearing so if ordering from outside of Yamaha always confirm specs before ordering