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Discussion Starter · #1 ·
If you have been reading about all the reverse issues then you have read my posts on the mechanical aspects of the problem. Namely the obvious wear of the part called a "coupler" where it shows a wear mark where the reverse gear splines interface with it. The wear makes a small sharp step in the coupler. The sharp step makes it hard for the 2 parts to slide when shifting and there is pressure from the belt dragging in the primary clutch when idling. Shut engine off and it shifts.

This spring, it was time to fix my 2013 1200 with mechanical lever, as I having to shut off the engine to be able to shift, some of the time. This machine had been "fixed" at 7,000 miles with a new coupler and the reverse gear splines getting a small lead hand ground on them.

The above fixed worked well but I was now somewhat disappointed that it lasted only about 11,000 miles. So I disassembled the sled and inspected the parts with a microscope to see what had happened.

Here's what I found.

The coupler was worn again but a bit differently. The worn section was more pitted or uneven than the original wear pattern. I don't know what this means but that's what I saw. The "step" had a more rounded curve to it but at the very end there was a sharp step starting to form again.

Now I inspected the reverse gear and I found something new! In the past, myself and others on Doo Talk, speculated that the gear likely is worn too but could not prove it. Now with 18,000 miles on the gear, looking at the spline at 20x at the ends you can very clearly see that it is wearing too. I would guess at least as much as the coupler.

Now this gear was the first that I had added the "lead" or radius to the spline edge and it was a small lead compared to what I have been doing lately to other sleds. What I saw was the wear in the reverse gear was several thousands of a inch, enough to completely consume the lead I had ground in. The wear had created a new sharp edge on the gear. This new sharp edge was once again wearing a sharp edge into the coupler. This made it difficult to shift again. I think if this sled had had a larger lead it would of be shifting OK but only for a few more thousands of miles.

So my plan for this sled is to run it one more year to about 22,000 miles, sell it and buy a 900 turbo assuming the engine works out well after its first year in production. So to get the sled ready for the next season at least cost, I simply benched the coupler smooth and added generous lead with polished radiuses to the gear. I lapped the two parts together, cleaned and worked them together with some moly paste. Now shifts well again.

Let you all know the results next March. Hoping Doo changed the design in the wide Gen 4.

If you have a warranty and your shifting is acting up, try to get your dealer to replace the coupler and the reverse gear. The reverse gear is expensive!
 

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Thanks for the update Saber!

This is all good to know. When I had my 900 done under warranty 2 years ago it had about 7500 miles on it and they replaced the coupler, sliding gear and 24 T sprocket. That sliding gear is expensive @ $330!

It sounds like the metal being used may be too soft for this application or it is just the nature of the design. As you said, lets hope they changed the design in the G4.

I am wondering if a different chain case lube could help? I know there are a bunch of threads on chain case lubes and people are using everything from ATF to gear lube. I wonder if a different lube might help the wear on the mechanical reverse parts or it will take a different design and / or materials? :shrug
 

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Lube may help, it's amazing what different lubes can do. I believe the issue is with hardening, it's a fine line of being to soft (wear) or to hard (brittle). I wish my long time buddy was still alive, he new his stuff when it came to hardening and part failures, he was a genius. It will probably take a design change to solve the issue that many are having in the long run.
 

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Discussion Starter · #4 ·
I Ski Doo would just say they know and a improvement is coming I'd be happy. But I understand why they can't. I'm hoping the new shift linkage (the concept I like) is a cover for the real change inside. I believe all they need to do is increase the contact area of the splines and or a material change which is not that big of a change.
 

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Try a gl5 specced lubricant, they tend to keep helical and flat gears so slippery brass syncros overspins and create a crunching feeling to a shift in gl3-4 specced manual gearboxes. I guess it be a good property to the gearboxes in the skidoos
 

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Try a gl5 specced lubricant, they tend to keep helical and flat gears so slippery brass syncros overspins and create a crunching feeling to a shift in gl3-4 specced manual gearboxes. I guess it be a good property to the gearboxes in the skidoos
So that would point to the use of gear lubes.... something like an 80W-90. Differentials have gear to gear (spline to spline) contact under a lot of load. Maybe it would make sense to use a gear lube in the 4-stroke chain case since there is more involved than just the chain and sprockets as is the case with the 2-strokes.
 

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So that would point to the use of gear lubes.... something like an 80W-90. Differentials have gear to gear (spline to spline) contact under a lot of load. Maybe it would make sense to use a gear lube in the 4-stroke chain case since there is more involved than just the chain and sprockets as is the case with the 2-strokes.
We need test subjects!
 

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My 2016 Enduro 900 has 4800 miles and I am due to change the chain case oil before next season. I may give GL-5 80W-90 a try. The specs shows it is good to -20F.
 

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I have been using Redline heavy shockproof gear oil in my 09 8200 miles and 0 problems with the electric shift
 

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Can am gear oils are gl5. I usually just buy royal purple or quaker state.
I have had issues with Royal Purple and Quaker State oils. Quaker State oil is a real sludge builder, seen it many times in engines. Royal Purple to light weight and when used in my motor cycle caused gear rattle (engine and gear case connected). Glad you are having good luck with it. I strictly use Mobil 1 products, superior products and can be purchased just about every where.
 

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On my 16 1200 x 6450 mile manual reverse 3/4 the way through the season also decided to stop working only in shutdown mode and i run mobil 1 75/140 full syn and is gl5 and that has not helped for normal wear to the reverse. My 14 x and 15 x i no longer have had the same oil ran and both of them were also rebuilt around same mileage coupler and gear so in my case gearlube is not helping in my situation sorry, 16 is at dealer now getting taken care of under warr.
 

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On my 16 1200 x 6450 mile manual reverse 3/4 the way through the season also decided to stop working only in shutdown mode and i run mobil 1 75/140 full syn and is gl5 and that has not helped for normal wear to the reverse. My 14 x and 15 x i no longer have had the same oil ran and both of them were also rebuilt around same mileage coupler and gear so in my case gearlube is not helping in my situation sorry, 16 is at dealer now getting taken care of under warr.
Well that's disappointing..... so much for trying that approach to see if it makes a difference.

Sent from my iPhone using Tapatalk
 

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I use Klotz chaincase lube. It's loaded with graphite, which helps when metal rubs metal without lubrication. After 14k, I have not had any trouble with reverse (except when the belt height is incorrect).
 
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