Engine Temperature Gauge Problem

[travistodd1]

I am working my way through the little things which need attention on my M817. I have never been able to get a reading on the temperature gauge. I have only driven it around the block twice since getting it running. I have also let it sit and idle for 10 to 15 minutes at a time in near 100 degree weather and it is not registering at all. I understand neither I have not run it very much but am trying to prevent it from overheating and having a costly repair. I have replaced the gauge and sending unit with no change.

How long does it take one of these to warm up? Am I just not giving it enough time? I know my old Cummins trucks all have been painfully slow to warm up in the winter, never really paid attention in the summer.

As always, thanks in advance.

 

[simp5782]

Take the wire off at the sending unit and ground it out and see if the gauge twitches or pegs out. If yes then you got a flow problem if both units are known good. You would.verify the temp at the sending unit with an infared temp gun

If the gauge doesn't twitch when you ground it out run a new wire between the two and see what happens

 

[frank8003]

This is an important tool to use. There is hundreds of flavors out there, some very expensive to inexpensive. I always use Raytek because it has worked good for 25 years now. Use the heat gun before and during engine warmup. The metal and hose and tubing temperatures will explain a lot. Even new gauges lie. Useful for many jobs.
It will indicate loose wiring connections in home electric panels and in vehicals too.

 

[M35A2-AZ]

From a cold start you will not see the gauge move at idle. If you drive it 2-3 miles it should start to move up.

 

[travistodd1]

Take the wire off at the sending unit and ground it out and see if the gauge twitches or pegs out. If yes then you got a flow problem if both units are known good. You would.verify the temp at the sending unit with an infared temp gun

If the gauge doesn't twitch when you ground it out run a new wire between the two and see what happens

Sounds good, I will give it a shot.

From a cold start you will not see the gauge move at idle. If you drive it 2-3 miles it should start to move up.

Well, perhaps I need to line a few more things out and take a little drive. I am just worried about a breakdown. I really don't want to flat tow it again behind my Ram, that was one sketchy tow last time...

 

[M35A2-AZ]

If you put a ohm meter on the sending unit you should see it move as it heats up.

 

[travistodd1]

Take the wire off at the sending unit and ground it out and see if the gauge twitches or pegs out. If yes then you got a flow problem if both units are known good. You would.verify the temp at the sending unit with an infared temp gun

If the gauge doesn't twitch when you ground it out run a new wire between the two and see what happens

Sounds good, I will give it a shot.

 

[US6x4]

It takes 30 minutes of idling to get my M813 up to 120°