Ported Chaincase!!!

[BigTruck]

Well it happened again. Was riding with a good buddy of mine and low and behold the bottom sprocket bolt broke, spring washer got into the chain and you know the rest!! This is like the fifth time this has happened to people sleds that I have known. First time when I was actually there. I took the cover off got all the broken pieces out put chain and sprockets back on along with the cover and we rode another 50 miles that day!

Just had not heard of this for a while and wanted to remind people to check their chaincase hardware.

Will be installing new chaincase tonight.

 

[Lake Cle Elum]

Wow, good advise - I always use blue loc-tite when installing the bolt, but how does one check ahead of time to prevent a bolt from breaking? I wonder if those that broke had been over torqued at one time?

 

[GMCRMK]

Same thing happened to me. Bottom bolt on sprocket broke off. I never knew there was a problem until the bolt head would kick up into the chain. Made a helluva racket but I got lucky & it didn't do any damage.

 

[BigTruck]

The Problem!

Is the bolt itself. Grade 8. Many a Polaris have had this problem in the past. Go to the hardware store and replace with a grade 5. DO NOT OVERTIGHTEN!

Problem with the grade 8 is that it becomes brittle and with the spring washer creating pressure it breaks after time.

Food for thought.

Rob.

 

[TWOSTOKED]

Ride a sled with no chaincase.

 

[Wayniac]

I discovered that same problem on my '04 700RMK this fall. Luckily it caused no damage and I got the broken bolt out. I got a grade 8 Caterpillar bolt (they are the toughest hardware I have ever seen) and so far so good. The grade 5 idea might be the ticket though.

 

[Flakey]

Last weekend my bud rode his new 96 polaris for the first time, he heard a whine coming from the chaincase. So, we kept riding, no problems.

Tonight I pulled the cover to check it for him. Yeah, the washer fell out as I pulled the cover, looked down and the top sprocket nut was laying at the bottom of the case wedged between the chain and the case. It had a nce groove worn into it. lol

Can't believe that thing didnt blow the case, but I just cleaned up the nut, put it back together and added oil. Done.

Except now It has a cotter pin in it. I guess the last guy didn't think they were that important.

 

[GMCRMK]

So, the moral of the story for me is I will no longer just drain & refill the chaincase. Need to pull the cover & inspect the bolts too.

 

[audaveh]

Had the same problem with my 99 & 03 RMKs. Replace the tension washer with a good old fender washer, find a small washer to fill the void created between the end of the shaft and fender washer Tacoma Screw) and bolt it all together with a grade 9 bolt from Tacoma Screw. No more problems!