Polaris steps up big time ...

[sledder51]

2022 Pro RMK Boost, 2nd owner, 1,070 miles, lost power and stopped. Unfortunately it is 2 1/2 months out of factory warranty. Dropped it at the dealer, 3 weeks later they called with the bad news. PTO side piston ring locator pin fell out, piston ring spun, snagged on the port with catastrophic results. Pieces fell into the crankcase and destroyed the crank, pieces went through the turbo and destroyed it, obviously piston and cylinder destroyed.
Good news is Polaris is going to cover the entire repair; complete engine rebuild and new turbo, everything replaced except crankcase. Must be more cost-effective than a drop-in replacement.
Anyway, that's an amazing gesture of goodwill on Polaris' part and says a lot about them as a company. This is my 3rd Polaris sled with more to come in the future.

My thought is maybe this is a known, widespread problem that they are trying to make good on? I haven't heard much of this (ring locator pin) as a specific problem. I assume pistons have been redesigned.

 

[christopher]

Good news is Polaris is going to cover the entire repair; complete engine rebuild and new turbo, everything replaced except crankcase. Must be more cost-effective than a drop-in replacement.
Anyway, that's an amazing gesture of goodwill on Polaris' part and says a lot about them as a company. This is my 3rd Polaris sled with more to come in the future.

Congratualtions!

 

[Teth-Air]

2022 Pro RMK Boost, 2nd owner, 1,070 miles, lost power and stopped. Unfortunately it is 2 1/2 months out of factory warranty. Dropped it at the dealer, 3 weeks later they called with the bad news. PTO side piston ring locator pin fell out, piston ring spun, snagged on the port with catastrophic results. Pieces fell into the crankcase and destroyed the crank, pieces went through the turbo and destroyed it, obviously piston and cylinder destroyed.
Good news is Polaris is going to cover the entire repair; complete engine rebuild and new turbo, everything replaced except crankcase. Must be more cost-effective than a drop-in replacement.
Anyway, that's an amazing gesture of goodwill on Polaris' part and says a lot about them as a company. This is my 3rd Polaris sled with more to come in the future.

My thought is maybe this is a known, widespread problem that they are trying to make good on? I haven't heard much of this (ring locator pin) as a specific problem. I assume pistons have been redesigned.

It may not be that new pistons are the fix, it might be the tune. If the 22 flash was causing detonation it can easily kick out that pin. Polaris might know about that issue.

 

[BeartoothBaron]

Locating pin failures seem to be more common on Polaris engines going quite a way back, I think even to the Dragon 800s. It seems to have been less of a problem on the 850, but still happens. One theory as to the cause is ongoing detonation issues - sometimes just below the threshold of triggering the knock sensor and throwing a code. That might have caused the same failure on my sled a couple years back - I recently installed a permanent fuel pressure gauge and found it wasn't consistent. Could have been going lean and rattled the pin loose. Newer sleds like yours are more sophisticated, including being able to detect low fuel pressure, but that doesn't guarantee it's going to fully compensate for bad fuel or every riding condition - especially considering how much they've improved the mapping over the years.

Anyway, good to hear Polaris is taking care of it. Hard to say for sure if the dealer is hooking you up somehow, but it's hard to imagine Polaris would be covering it if they hadn't checked the right boxes for you.

 

[sledder51]

Locating pin failures seem to be more common on Polaris engines going quite a way back, I think even to the Dragon 800s. It seems to have been less of a problem on the 850, but still happens. One theory as to the cause is ongoing detonation issues - sometimes just below the threshold of triggering the knock sensor and throwing a code. That might have caused the same failure on my sled a couple years back - I recently installed a permanent fuel pressure gauge and found it wasn't consistent. Could have been going lean and rattled the pin loose. Newer sleds like yours are more sophisticated, including being able to detect low fuel pressure, but that doesn't guarantee it's going to fully compensate for bad fuel or every riding condition - especially considering how much they've improved the mapping over the years.

Anyway, good to hear Polaris is taking care of it. Hard to say for sure if the dealer is hooking you up somehow, but it's hard to imagine Polaris would be covering it if they hadn't checked the right boxes for you.

Locating pin failures seem to be more common on Polaris engines going quite a way back, I think even to the Dragon 800s. It seems to have been less of a problem on the 850, but still happens. One theory as to the cause is ongoing detonation issues - sometimes just below the threshold of triggering the knock sensor and throwing a code. That might have caused the same failure on my sled a couple years back - I recently installed a permanent fuel pressure gauge and found it wasn't consistent. Could have been going lean and rattled the pin loose. Newer sleds like yours are more sophisticated, including being able to detect low fuel pressure, but that doesn't guarantee it's going to fully compensate for bad fuel or every riding condition - especially considering how much they've improved the mapping over the years.

Anyway, good to hear Polaris is taking care of it. Hard to say for sure if the dealer is hooking you up somehow, but it's hard to imagine Polaris would be covering it if they hadn't checked the right boxes for you.

I wasn't aware of pin failures dating way back. My sled does have the 2023 flash done and I religiously use 91 non-eth with a couple gallons of VP110 every tank. I haven't experienced any detonation issues running that combo. Thanks for the response.

 

[BeartoothBaron]

Sounds like you're doing the right things with regard to fuel. There are, of course, other potential sources of locating pin failures. The added octane is a good idea, and I'd say probably eliminates detonation as a cause. That said, no det codes doesn't guarantee anything: what can happen with just a little too much timing or too little fuel is combustion characteristics half-way between ideal and detonation. There's a narrow window with over-advanced timing where power will drop off but detonation will be minimal or undetectable. It may never hurt anything (especially on a four-stroke), but peak cylinder pressures jump quickly in that zone, which the piston "sees" like being smacked instead of shoved. The dominant theory with locating pin issues (mostly on CFI and HO 800s) was that it didn't take much - bad gas, drop in fuel pressure - to push them into that zone, and the electronics weren't sensitive and sophisticated enough to catch and compensate for it.

Bit of a long explanation, but hopefully it helps. The one ongoing piece of advice on any engine failure is don't assume it just ate itself for the fun of it. It's kind of tricky when it's the dealer doing that work, but generally you'd want to check over the injectors, reeds, intake track, wiring, etc. Should be kind of silly on such a new sled, but digging through the laundry list of issues with Boosts says it's not.

 

[diamonddave]

This is good news. For as much as I have bagged on them (sarcastic fun), it’s good to hear they are taking care of a 2nd owner out of warranty.

One of the more common piston failures I am aware of is the separating of the piston, the crown above the ring groove. Oddly enough, I haven't seen it yet on this forum. I have some speculation as to why this is happening with the boost in production applications. Need more data.

 

[Chadly]

This is the new American way. Let's help poor people because rich people are bad.

 

[sledder51]

This is the new American way. Let's help poor people because rich people are bad.

WTF does that mean? I’m guessing maybe based on the time of your post, you mistakenly responded to my thread instead of your thread on Reddit “I hate Donald Trump” after a long night of drinking and hallucinogens.

 

[NHRoadking]

This is the new American way. Let's help poor people because rich people are bad.

Not all of them are bad. Just the ones who design/build crappy stuff that we ride on.

 

[AdrenalineAddict]

The ring retaining pin failure has been an issue for decades. I have personally seen failure after failure. The pin falling out is almost like clock work, I’ve found that 2,000 miles or 102 hours is the failure point.