Bad wire connection causing high temp reading?

[dlundblad]

Somewhat of a back story. I bought a G5200 last December from a guy who had it for about 30 years. Used it to mow and blow snow, but it never had a temp gauge.

I have since installed a temp gauge and sensor (plug and play), flushed the radiator, added new coolant, tightened the fan belt and made certain the radiator and screen is clean. The thing looks to be running hot on the gauge, but physically it doesn’t feel abnormally hot. The whistler isn’t going off either. I was messing with the wiring yesterday while mowing and it seems to be reading a more ideal temp now. I should also add that it doesn’t appear to be using coolant so hopefully it’s not the head gasket.

Would dirty connections cause a high reading? If not for me adding a temp gauge, I wouldn’t think there was an issue.

 

[Palmettokat]

Yes a bad connection can affect the transmission of electricity. Are you sure the unit you have is made for that machine and it is not defective. Use a infrared thermometer to check the system.

 

[dlundblad]

All the parts are from similar vintage G tractors.

 

[GeoHorn]

A bad connection (such as loose, corroded, etc) would likely give a LOW indication. Perhaps your initial reading was good...but now you’ve got a bad connection making it read LOW.

Stick a thermometer (BBQ, etc) into the fluid at the radiator cap to see what the actual temp is.

 

[SidecarFlip]

A bad connection (such as loose, corroded, etc) would likely give a LOW indication. Perhaps your initial reading was good...but now you’ve got a bad connection making it read LOW.

Stick a thermometer (BBQ, etc) into the fluid at the radiator cap to see what the actual temp is.

Better yet, use an IR digital thermometer on various points of the engine to get some readings.

 

[kubotasam]

When I bought my B7500 a few years back I noticed it would read hot all of a sudden while running. I first suspected a head gasket or cracked head. Turns out it was caused by a bad ground going into the instrument cluster.

 

[dlundblad]

When I bought my B7500 a few years back I noticed it would read hot all of a sudden while running. I first suspected a head gasket or cracked head. Turns out it was caused by a bad ground going into the instrument cluster.

Very interesting. The cluster came off a G that was sitting in the back of my dealer for years. Perhaps something is corroded.

 

[dlundblad]

Somewhat of an interesting update. It reads hot, but once again isn’t hot to the touch.

It is reading about 186*F at the t stat housing with an infrared gun. Likewise, I mowed with dads G1800 diesel (essentially same engine; I assume it’s fair to say they should run at about the same temp) and it was reading about 216*F at the t stay housing. The gauge was reading halfway between hot and cold so nowhere close to overheating, but it was running hotter than normal because the radiator was full of grass. I am convinced it’s electrical and not mechanical.

Looking back, would checking the head where the temp sensor is located be better?