My 2018 Cforce 500 HO continues to overheat. Last time the top of the piston had carbon and the cylinder walls had dark staining midway down. Cleaned it up and turned down the fuel controller. Replaced the thermal switch in the radiator. Did a radiator relocation kit to keep it clean, put the top end back together with a new head gasket. It was staying at 2 bars, the radiator was getting hot, the fan was coming on. It was keeping it at 2 bars temp. 5 minutes later it got hot and blew the head gasket for the 3rd time. I guess tear it down check to make sure the surfaces are straight, check thermostat, water pump, temperature sensor. Anything else you can recommend?

[2015 Z Force 800 53/Trail EPS]

What's this fuel controller you talk about...something aftermarket? Overheating from fuel usually stems from a lean condition not rich.  Overheating also means it went to the top of the scale and the hot warning light came on but you didn't mention that. Only that it gets over 2 bars then gets hot and blows the head gasket...and has done so three times. That sounds like a surface warp-age of some type or maybe a crack somewhere. Three bars is the norm with these for operating temp. Could it be there is an issue with the temp sensor? Also radiator relocates are sometimes tricky on some of these as air pockets and hard to get out and if one is at the temp sensor...it won't work

Fischer Brothers Attitude Box Fuel Controller was put in a long time ago. I will remove it just to eliminate that as the cause. The coolant lines run horizontal then vertical, no dips to trap air. I installed it because the radiator would get packed with mud. Yes the carbon inside and the high temperature lean doesn't make sense. I thought since the display gauge would cycle between 2 to 3 bars and then go to 5 bars after 5 minutes the temperature sensor is working. It does sound like there may be a leak, I will check compression this time. Thanks for your questions and advice.

wrap the pipes .... bro....


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