What causes a bulkhead closeoff to crack? 2019 Axyx 850

[tb123]

My bulkhead closeoff plate is cracked near the rear right engine mount (see attached photo). I'm curious if anyone else has seen this? There really isn't any other damage that I can see, but the sled was purchased used so I don't know what the PO might have already replaced.

I'm in the middle of replacing the plate as I believe clutch alignment will be effected as the engine torques. What else should I carefully inspect for while I have everything torn down?

 

[tb123]

Well, after further inspection, I found a tiny crack in the the left side bulkhead. You couldn’t see it until I pressure washed the exterior (which wasn’t even that dirty).

 

[kanedog]

Post the guys name that sold it to you. Let’s stir up sum chit!

 

[tb123]

Post the guys name that sold it to you. Let’s stir up sum chit!

Ha, I’m not going to do that, although it’s tempting as I assume he was aware of the damage. The close off plate damage is very visible with the silencer removed. The sled had a stock exhaust on it when I bought it, but given the other mods, I doubt he was running the stock silencer. I’m sure the seller took his can off right before selling and couldn’t have missed the damage.

All that matters now is getting it fixed before the snow gets good!

 

[Sheer]

Mine cracked in the exact same spot, not as bad as that one, it was strange it wasent from an impact - i give my sled a brief checkover after every ride and saw that crack one day - the ride prior was pretty tame with no tree hits, i rubbed the outside of my ski agenst a very small tree (missed the tree but the tree turned me) that ride, and i was wondering if that caused it, and i rolled it over a few times to get un stuck and maby from the chassies twisting did it, i dont know, but ive defently hit things harder and done much worse with no damage to the frame, there wasent even one point in that ride where im like i hit something hard i should stop and check tipe of thing.. anyway it was still under warrenty at the time and that piece broke and with no external damage i wanted it fixed, polaris sortof half came through and authorized to have it welded and said if it continues to crack after that they would replace it, its been a few years since and its been fine but my crack was only about 1.5 in long

 

[tb123]

Mine cracked in the exact same spot, not as bad as that one, it was strange it wasent from an impact - i give my sled a brief checkover after every ride and saw that crack one day - the ride prior was pretty tame with no tree hits, i rubbed the outside of my ski agenst a very small tree (missed the tree but the tree turned me) that ride, and i was wondering if that caused it, and i rolled it over a few times to get un stuck and maby from the chassies twisting did it, i dont know, but ive defently hit things harder and done much worse with no damage to the frame, there wasent even one point in that ride where im like i hit something hard i should stop and check tipe of thing.. anyway it was still under warrenty at the time and that piece broke and with no external damage i wanted it fixed, polaris sortof half came through and authorized to have it welded and said if it continues to crack after that they would replace it, its been a few years since and its been fine but my crack was only about 1.5 in long

After further inspection, I also found a hairline crack in my left bulkhead casting. My sled has been down all winter so far... good year for it with no snow.

I pulled the bulkhead and closeoff plate and I'm currently reassembling. Does anyone know if I am to use Lord 406 adhesive on the mating surface between the tunnel sheet metal and the closeoff plate (I already riveted it on without it so I hope not)? There was no adhesive used in this location from the factory (upon inspection after removing my cracked plate), but the 2020 155 service manual shows it being used here if the sled has a cooler. I have a 2019 163 without a closeoff cooler. Does anyone have a copy of the 2019 163 service manual to check this for me? Thanks!