09 800 dragon blown

TJGDragon

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Has anyone tried putting the 860 big bore kit for the fix. My sled is still running but I have no more warrenty so I figure if I have to replace the motor anyways I will try the big bore kit its a little more money but if it lasts longer its worth it.
 

timbo

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Has anyone tried putting the 860 big bore kit for the fix. My sled is still running but I have no more warrenty so I figure if I have to replace the motor anyways I will try the big bore kit its a little more money but if it lasts longer its worth it.

Carl's cycle kit is expensive and they told me they only tested kit at elevation.One customer of theirs has rode his at 3000 ft but no lower.I ride mine here so I didn' look any further into it. For that kind of money you could boost it and have the same luck.The Fix that I ordered is only $100 more than if you bought Polaris pistons,rings etc.
 

shady877

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ok thanks guys ill try drilling holes or something like that. I think pretty much anything we do cant hurt since they blow up as is haha anything's worth a shot
 

shady877

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Has anyone tried putting the 860 big bore kit for the fix. My sled is still running but I have no more warrenty so I figure if I have to replace the motor anyways I will try the big bore kit its a little more money but if it lasts longer its worth it.

Try asking for the polaris goodwill warranty from your dealer. I have no warranty left but theyre gonna pay for all the parts, just not labor. Its not free but it helps big time. If it happens again, I think im just gonna steal the engine out of my dads lawnmower its never had a problem
 

Caddydaddy

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Got 1 - 07' 700 Dragon (Engine Blown @ 1258mi), 08' 700 RMK Engine Blown @ 952mi, 2nd engine lasted 82 miles, 08 700 RMK Engine toast at 1245 miles. All caused by lean-out condition on the PTO Cylinder. Glad I spent the $27K on new sleds.
 

sirkdev

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You guys work wayyyy to hard to make these run, cut your losses and move on sledding season is too short.
 

BrosBeforeHos

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Got 1 - 07' 700 Dragon (Engine Blown @ 1258mi), 08' 700 RMK Engine Blown @ 952mi, 2nd engine lasted 82 miles, 08 700 RMK Engine toast at 1245 miles. All caused by lean-out condition on the PTO Cylinder. Glad I spent the $27K on new sleds.

My 09 800 Assault just grenaded again, even after the update....for the 3 time. Polaris pays for the parts, I pay the labour. I've heard it all from snow ingestion to injection timing between injectors. There is no way Polaris knows of a fix...they leave that to us:rolleyes::beer::beer:
 

BrosBeforeHos

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I've been reading alot of articles on the subject of these 800's blowing up. I just read another article in SnowTech magazine about the thermostats in these CFI 800's having "a bypass hole which allows a minimal amount of coolant to circulate through the cooling system prior to the thermostat opening. This eliminates hot spots that can arise if the coolant is stagnant in the cylinder and head area. PTO cylinder on the 800 CFI will bypass through the throttle bodies. The coolant in the MAG cylinder on Dragon RMK and Assaults is required to bypass through the small hole in the thermostat plate. We have seen this hole plugged on some sleds. When that happens, the coolant in the MAG cylinder will develop hot spots prior to the thermostat opening. This can result in engine damage if the machine is operated prior to it's warming up to operating temperature. We recommend checking your thermostat to make sure the bypass hole is not plugged." Good advise...unaware of this bypass hole. Just some info for you guys who don't know about it.
 
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big09dragon

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i went to wisconsin this last week and my sled was still not running right. Im trading it in on the 2011 switchback assault.
 

timbo

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I've been reading alot of articles on the subject of these 800's blowing up. I just read another article in SnowTech magazine about the thermostats in these CFI 800's having "a bypass hole which allows a minimal amount of coolant to circulate through the cooling system prior to the thermostat opening. This eliminates hot spots that can arise if the coolant is stagnant in the cylinder and head area. PTO cylinder on the 800 CFI will bypass through the throttle bodies. The coolant in the MAG cylinder on Dragon RMK and Assaults is required to bypass through the small hole in the thermostat plate. We have seen this hole plugged on some sleds. When that happens, the coolant in the MAG cylinder will develop hot spots prior to the thermostat opening. This can result in engine damage if the machine is operated prior to it's warming up to operating temperature. We recommend checking your thermostat to make sure the bypass hole is not plugged." Good advise...unaware of this bypass hole. Just some info for you guys who don't know about it.

Read somewhere Carls Cycle recommends drilling two more holes to let even more water bypass through the thermostat.
 

OnlyPolaris

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I've been reading alot of articles on the subject of these 800's blowing up. I just read another article in SnowTech magazine about the thermostats in these CFI 800's having "a bypass hole which allows a minimal amount of coolant to circulate through the cooling system prior to the thermostat opening. This eliminates hot spots that can arise if the coolant is stagnant in the cylinder and head area. PTO cylinder on the 800 CFI will bypass through the throttle bodies. The coolant in the MAG cylinder on Dragon RMK and Assaults is required to bypass through the small hole in the thermostat plate. We have seen this hole plugged on some sleds. When that happens, the coolant in the MAG cylinder will develop hot spots prior to the thermostat opening. This can result in engine damage if the machine is operated prior to it's warming up to operating temperature. We recommend checking your thermostat to make sure the bypass hole is not plugged." Good advise...unaware of this bypass hole. Just some info for you guys who don't know about it.

the regular rmk models do not have this hole in the thermostat. i would suggest drilling three 1/8" holes in the thermostat to help with circulation. I would also look at the slp bypass kit and put something similar to it on the sled.
 

rmksledder

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here are some pics of the gizmo that i have installed on my 09 d8, easy instalation, have yet to try it just in the process of putting motor back together. thought it was atleast worth a try, sorry about the quality
 

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schtann

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Blew up 09 shift 800 2 days ago and not apart yet but MAG side seems
squeeked. After blow up the Irridium plug white color on MAG and PTO was perfect. Ran another ~10 miles just on PTO side to get back onto trailer- nothing but backfiring but better than at end of ROPE !! Checked and now 0 compression MAG and 85 PSIG on PTO. Not happy this P of S !!! Has SLP pipe and can c/w high flow air box kit and NO PC-V but ordered it a week ago and not here yet- WOW !!! 91 octane always and pre-mix in the tank just like SLP said. Then this happens !! Supposed to already have the 2 ring piston, NEW heads, and latest reflash. Engine warranty just went off it
as I'm the second owner. Maybe I should not be an owner !!! Offers $$$ ?? Run Polaris for ~25+ years and never, never believed this could happen. About 1200 miles on the chassis. very,very disappointed and already put on ~500 miles this season with no sign of this trouble and all of a sudden- KABBOOOMMM !! Anyone know of parts available ASAP and who from ?? Have emailed a few already and await replies. BE AWARE !!!! CFI 800 4 injector motor is a BAD ONE !! But then most of you already know that !!! :rant:
 
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