Diamond drive issues

[tantrumpipeline]

Read all the FAQ posts can't figure out my issue, have everything as shown in the pics but as soon as I tighten the cover I can't evenly close the gap even stripped 3 holes on the case trying, once it tightens if feels like its binding bad but until it gets pressure from tightening its spins perfect? Any ideas?

 

[moyiesledhead]

If you've updated to the wider planetary bearing on an 07 DD I've found you can't just slide it on where the narrow one was. It'll hold the cases apart. The shaft has to be machined to allow for the wider bearing.

 

[tantrumpipeline]

Figured its be stupid, will my 11 require the same?

 

[Stg2Suby]

09+ is hit and miss, depends how the tolerances on the parts add up, most go together with none or minimal interference but the odd one ends up requiring something to be machined. Endless controversy over whether the machining is required or not; it certainly doesn't hurt if you have the ambition but many have gone together with some cover flex and suffered no longevity issues. Keep in mind the 3203 bearing is angular contact and designed for significant axial loading.

 

[tantrumpipeline]

Thanks ill let you know how it goes just need to do some cleaning again and re install this narrower bearing

 

[Slamnek]

I did not have to machine anything on my 09. The cover went on perfect.

 

[tantrumpipeline]

The 07 would have required machining so it was replaced with the sticker, my 11 was a direct swap to the wide bearing

 

[Demon13]

I updated both my 09 HCR and 11 M8 with the 3203, no issues.

 

[tantrumpipeline]

just finished an 09 the other day, the 08 and older have a different case I think that's why the machining is required, the newer ones I've opened up have all fit now

 

[crossfire879]

I have done the bearing upgrade in my 08 and it didnt need to be machined.... it must just be a hit or miss thing.

 

[Paul2727]

It all has to do with your tunnel dimensions. Arctic Cat had poor QC during tunnel manufacture. Some tunnels are welded together too narrow, and that makes your track drive shaft too long for your tunnel. The only way stuff can move is for the track drive shaft to push on the DD output shaft (pushing it into the DD), which pushes on the 6203 transfer bearing, which pushes on the DD transfer shaft, which pushes the DD aluminum cover outward. All that pushing and shoving holds the cover open, not allowing it to close properly (in some sleds and not others). When you tighten the DD cover bolts, the sides of your aluminum tunnel will be flexed outward, misaligning all the bearings and overloading the weak little 623 bearing.

In my case, with my 2011 HCR all bolted up, it had 1/8" total spring (1/16" per side) in the aluminum tunnel. A new 3203 (5203) bearing fit fine in my DD, with no transfer shaft machining. My track drive shaft had to be machined 0.130". There are pictures on another post: Another DD Bearing Failure - 5203 this time - SnoWest Snowmobile Forum and https://www.snowandmud.com/forum/456/diamond-drive-bearing-upgrade-thread-lots-47974-7.html

Other A/C tunnels are wide enough, so you don't have any shaft pushing & shoving. And no axial load on your 6203 bearing.

Good Luck!

 

[IGBT]

hmmm. I put in a SKF 3203 in my 2011 Snopro M8 and did machine the bearing shoulder but after reading that thread on SnoWest I am concerned about the track drive shaft and also that bearing shield on the brake side (I can probably check to see if that part is missing without taking things apart).

I think I will stick with my plan of putting a few hundred miles on the 3203 and then take the DD apart again and inspect it.