my water temp light is on dimly at engine start up and then brightens as engine warms. The actual engine temp is perfectly fine , as i have checked it with an infrared gun as it warms and in several area on the engine. are there to temp sending units? I just installed a complete brand new engine but used all of my old sensors/sending units.
water temp light is on but engine is not hot
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There is a sending unit for the gauge and a separate switch for the light. I think the sender is top of the waterpump housing (near the thermostat) and the switch below the alternator bracketry. Cheers!
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Mine did this once when I first got the truck after I went up a really steep hill. I check the fluid and temp and it was fine. Went off a few days later. Air bubble in the system maybe?
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Air Bound?
still can not find the switch
makes sense what he said about the "light" switch. Went to napa and got new switch, but don't see where it goes. I see the "one wire" sending unit on top of the water pump right beside the thermostat, but do not see the other sensor for the light. And why , if it is a switch, would the light be dim at start up and grow brighter as the engine warms. It has been constant since engine installation, and has never fluctuated. ALWAYS dim when engine is cold and brightens as it warms up. The gauge does not seem to ever move, but it was that way before installing the new engine. And also, NAPA could only find the "two wire" sensor, and did not show any other coolant temp sensor. By the way just found this site. Appreciate the help. Tremendously!!!!
makes sense what he said about the "light" switch. Went to napa and got new switch, but don't see where it goes. I see the "one wire" sending unit on top of the water pump right beside the thermostat, but do not see the other sensor for the light. And why , if it is a switch, would the light be dim at start up and grow brighter as the engine warms. It has been constant since engine installation, and has never fluctuated. ALWAYS dim when engine is cold and brightens as it warms up. The gauge does not seem to ever move, but it was that way before installing the new engine. And also, NAPA could only find the "two wire" sensor, and did not show any other coolant temp sensor. By the way just found this site. Appreciate the help. Tremendously!!!!
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The switch in near the alt bracket. Kinda tucked in if I remeber right. Ya I had trouble finding the correct sensor for my truck too. My gauge has never worked but goes all the way to hot when you ground the lead. I dont know whats wrong with it. Probally the gauge itself cause ive tried a few diffrent senders. LMC truck has the correct one. Ford has it too if you bring in your old one to match. Ive given up, the gauge has never worked so Im not used to watching it anyway. Im just gonna put in an aftermarket that more accurate anyway.
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Follow the wiring harness up from the cam position sensor as the wiring for the switch is in the same harness. Cheers!
temp light fixed but alot of cranking to start after sitting
sensor and sending unit were turned around on the temp gauge and light. On my truck, for some reason, both of them have the single wire and the same connection style. I have put about 100 miles on the engine now, but after sitting over night it takes ALOT of cranking before it fires. Glow plugs are all new and are working ok, and it makes no difference if it is left outside (25degrees) of if left inside (65degrees)
sensor and sending unit were turned around on the temp gauge and light. On my truck, for some reason, both of them have the single wire and the same connection style. I have put about 100 miles on the engine now, but after sitting over night it takes ALOT of cranking before it fires. Glow plugs are all new and are working ok, and it makes no difference if it is left outside (25degrees) of if left inside (65degrees)
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