Operating Temp Issue....

[pcblakeley]

I I just went out and started my truck and checked the lights and new alternator and I think I may have a little issue with the temperature.

I was intending on warming up the truck to operating them to check all the gauges and fluids.....so i let it warm up for about 8 minutes and hopped in the cab to look at the temp and it was all the way at the left (Cold) I tapped on it a few times and it hopped all the way to 220, I secured the power to the gauge and then repowered it and the needed indicated 220 again.

I turned the truck off and popped the hood to look and feel around and the entire block, radiator hoses, water pump, coolant and associated underhood components were barely warm.

The fluid was lukewarm in the radiator and it had built up a small amount of pressure.

The top and lower radiator hoses were the same temperature as the water pump.

Above and below the thermostat was the same temp.

I did notice that the radiator cap was a little loose when I went to remove it.

I am thinking that the gauge is faulty but I am not too sure.....What do you guys think

 

[sandcobra164]

Pretty sure it's a gauge or wiring issue. After 8 minutes of idling, the one's I've been around aren't registering anything yet.

 

[pcblakeley]

I started it cold and tapped on the gauge....sure enough it went straight to 220.....

I guess I will be tracking down a new gauge.

Thanks SandCobra!

 

[jwaller]

my 809 takes about 30 min of idling to even move the gauge.

 

[LanceRobson]

Unless you run it at 1,300 or 1,400 RPM with the radiator covered the thermostat is unlikely to ever fully open. If it's an M809 series truck the temp with it fully warmed up should be 175-195F.

Without digging into the -20 manual I don't know if an over range gauge is caused by a gauge or a wiring issue but you might want to check which causes it before buying any parts. It could be a simple as a bad wire or ground.

Lance