I'm trying to diagnose the issue of my '86 K100 overheating. The temperature light turns on after a few minutes of riding. The fan doesn't turn on so I'm starting from there. I read in my Haynes manual (pg. 123) that testing the thermostat is the first issue to rule out. I did as they suggested, suspend the thermostat in a pot of water and heat it up to see if the thermostat opens. I think that's a bit unusual being that opening it up needs a bit of pressure from the other end (as in the picture of me pressing it opened- ouch!). Anyhow, as the thermostat sat in the pot, I brought the water to a boil. Thermostat for dinner, anyone? :laugh Anyway, at this point, should the thermostat have opened? Because it did not. I felt a bit silly doing this in my kitchen, but I needed to know if an improper working thermostat is the cause of my overheating. If the thermostat has malfunctioned, would that prevent the fan from coming on? As it boiled, the thermostat looked the same as in the picture of it standing alone. Any help is appreciated.
