Temp Gauge Inop?

[VFMerc]

While idling my Farmall H after replacing the radiator, the engine temperature gauge began rising normally then stabilized in the normal operating range for a few minutes. Just prior to shutdown, after confirming no leaks, I observed the needle fall back to the cold peg. I ran the engine for about five minutes today. The engine idled normally and although the manifold warmed up the engine temp gauge never came off the cold peg. A look inside the radiator seemed to indicate normal coolant circulation.

Would appreciate a recommendation on the best sequence of steps to trouble shoot the system. Thanks in advance.

 

[Jim.ME]

As I posted in your original thread about this.

Your H should have a mechanical temp gauge I believe. Five minutes is a bit short of a time to make a judgement on during engine warm up. You should watch it longer and under load, not just idling.

If you have a temp gun, check the temp where the probe goes into the engine and see if it matches the gauge reading. The other option is to remove the probe from the engine and suspend it in a pan of water and with another thermometer it the water heat it up watching to see if the two thermometers hold about the same reading as the water is heated.

If it is a mechanical gauge, you run a 50/50 chance of damaging the tube removing the probe from the block (at least that has been my luck). I would by a new gauge and install it as the probe, capillary tube, and gauge are sealed together, it is not an electric gauge with a separate sender, unless it was changed from original.

 

[560Dennis]

Suggest ,I take the cap off ( carefully don’t get burnt) and put thermometer in the radiator coolent to see what temperature is there . If the thermo stat is missing or stuck open I’d replace it with new . The engine needs to come up to operate temperature to run efficiently and not build oil sludge in crankcase.
Check belts tension is correct,just part of t he service.