Temp. gauge reading Hot need help

[sebas54]

Hi I have a merc. v6 4,3l alpha 1. I have been trying to figure out why I was running hot. Today I installed a new temp sending unit and let it run on the muffs for about 20 mins. The gauge read around 180 - 200. Once I truned the engine off and put the key into aux the gauge read 140. Once I turned it back on it went all the way to 200 again. I felt the engine and it was cool. (Thermostat is a 160)


I want to replace the gauge but I am not sure if this will solve it.

Thanks for all your help.

 

[joncrisler]

Re: Temp. gauge reading Hot need help

buy a cheap infrared remote thermometer and check the top of the thermostat housing while the engine is running. Outside temp will probably be 5-10 degrees less than internal temp. This will help determine if it really is running hot, or the gauge or sending unit or wiring is faulty.