The 17s did have issues with the lower end crank/rod bearings. My buddy and I each bought one (3 vin # apart). Mine failed at 300 miles. His failed this past year at 2300. I had a dealer tell me that, at a BRP meeting, they admitted the 17s were failing at a 2% rate.
In general, if it fails and just seizes, the top end is reused. If in the case of our second one, it seized, threw metal from the rod bearing, cracked the water jacket under the rod and scarred up the jugs/head (probably reusable). But we just opted for a used motor I found in a sled on auction.
I believe ( I have no hard evidence, maybe someone that has played with BUDS can elaborate) that BRP upped the amount of being pumped to the crank (or pumped in general). The later models do not seem to be failing as often from what I can see--I have a lot of friends that ride doo and have had no issues. I can tell you the 2019 donor sled I got had a lot of oil in the tuned pipe when I pulled it (which I've been told is normal on the later years). I think they were trying to keep oil usage, smoke and smell down and got a little too skimpy. the later models seem to smoke more which is ok with me.
I am also going to put this in a separate thread, but you can use the 2017 harness on a later model engine. I didn't install SHOT as our 2017s never had it, but the capacitor was not working either on my donor sled/motor, so I left it out and the harness worked fine. I did transfer the ECU and oil pump from the donor sled. Had a mechanic that has BUDS clear the codes and reset the correct chassis code in the ECU and it then was happy. But I cannot confirm if SHOT will work. FWIW...
And both are going up for sale soon. $6750 OBO/each.
