Been trying to help my buddy sort out is xpt. It runs fine at low rpm, but once you hammer down it takes off, then has a hiccup like you let off the gas then takes off again. After driving at high rpm for maybe a minute or less it begins overheating drastically and then shuts down or is too hot to drive. Little bit of back story. He was riding the dunes and the coolant hose blew off at the thermostat hosing. Its hose clamped on now. He changed to engine ice (can you run that in the rzr?) Car ran fine for a full day. Now it does this every attempt out. We’ve done the bleed process multiple times. All air is out car runs fine at low rpm and no air comes back. Put the car underload and it gets air back in the system. We tried changing the tstat as well. Compression is lower its reading 120 in both cylinders. He has evo stage 4r and all required parts. He also has upgraded head studs. Talked to a few places and they just want it brang in. Someone told us possibly the head gasket, but wouldn’t there be oil in the water if that was the case? Anybody with any ideas let me know. Really don’t want to take it to the dealer, but its getting close to that. Thanks!
Utah RZR Rentals

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