Yamaha Exciter II overheat

stormbringer

New member
1992 Exciter II 570...broke the cock valve that controls the coolant flow to the carbs, so I removed it completely and plugged those hoses. Lost some coolant while doing this...but rode all day without any problems. Brought it home and put it away for the summer, and just now getting it out this year to find an overheating problem. Looking at various parts diagrams I don't see where it has a thermostat, so does the coolant flow through the heat exchangers all the time unrestricted? The heat exchangers and lower coolant hoses remain cool to the touch, and its the upper coolant hose that gets hot (of course, thats where the sensor is for illuminating the hot coolant indicator light). What is likelihood that the water pump went bad sitting over the summer? Or maybe coolant air lock?
 

jimfsr

New member
thermostat is in the top of the head, where the hose comes out. The water pump is belt driven, check the belt.
 
Take the seat off, and under there there's bleeder fittings in the pipe that crosses over between heat excangers. you probably still have air in the system and check the belt also like jimfsr said
 
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