Fuel and Temp Gauges went wonky

[csheath]

My fuel gauge quit a while back. It started back working while testing. Today I was showing my wife how to start the generator and manage loads during one of the 4 outages we had. She didn't hold it in start long enough and it shut down. When she restarted it the fuel gauge was dancing back and forth and the temp gauge was pegged. I shut it back down and restarted and both worked as they should. During the next outage all looked okay when I started it but when I went to turn it off the temp gauge was pegged again.

Printing a screen shot of that section of the wiring diagram so I can troubleshoot it tomorrow. I am assuming a loose or corroded connection somewhere. If anyone else has seen and corrected this I would appreciate knowing what you found.

 

[Guyfang]

Are you sure the temp gage is not telling you the truth? Dont assume anything. Test. Get one of the IR test guns, shoot the engine block when the gage is too high.

Basicly, the wire runs from the sender, to a TB, and then to the relay, then to the gage. Check it, wire number for wire number. , But test to see if the engine temp is normal or too high.

 

[csheath]

Yeah the first time it went pegged with a cold engine. Second time there was no indication of over heating other than gauge reading.

 

[jamawieb]

Check the connections on the gauges, I've had a couple that came loose and would do the same thing. Mostly grounds.

 

[DieselAddict]

Check the connections on the gauges, I've had a couple that came loose and would do the same thing. Mostly grounds.

What he said.. My money is on a bad connection in your ground path.

 

[csheath]

Looks like the gauge is bad. Base nuts on connections were a little loose but that didn't fix it. Cold resistance on sensor wire was 440 ohms. Running voltage to power connection with negative lead connected to gauge ground is 26 volts. Engine warmed up and reading 180 at thermostat housing via IR, sensor resistance 45 ohms.

This unit had both the fuel and temp gauges replaced at it's last military service.

 

[Guyfang]

What do you call a military service?

How do you know that things got changed?

 

[csheath]

What do you call a military service?

How do you know that things got changed?

You tell me?



It has a decal that reads RESET but no plate or indication that included a new engine or anything that drastic.



It had documentation that says the fuel and temperature gauges, among other things, were replaced at 2616 hrs.





The fuel and temperature gauges look newer than the others.

 

[boatman69]

Take the sensor wire off the gauge and Power It Up. If the gauge is still pegged hot the gauge is bad. If the gauge goes cold the sense wire is shorted to ground somewhere. Put it all back together and unhook the wire from the sending unit. If the gauge now goes down the sending unit is shot.

 

[csheath]

Take the sensor wire off the gauge and Power It Up. If the gauge is still pegged hot the gauge is bad. If the gauge goes cold the sense wire is shorted to ground somewhere. Put it all back together and unhook the wire from the sending unit. If the gauge now goes down the sending unit is shot.

Done did all that.

 

[Guyfang]

You tell me?

A service is directed by the LO 9-6115-642-12.

RESET is in directed by TB 11-6115-741-24



It has a decal that reads RESET but no plate or indication that included a new engine or anything that drastic.

View attachment 697283

It had documentation that says the fuel and temperature gauges, among other things, were replaced at 2616 hrs.

THis appears to be a WORK ORDER confirming that the following things were done or changed. The Owning Unit is RESET GROUP 2. I am not sure this means Tier 2 RESET. Because the TB clearly states that when Tier 1 or Tier 2 is performed on the equipment, a tag stating so, WILL be riveted to the generator set. But who really knows. Take a look at the TB, and compare the changed parts, with what the TB call mandatory replacement parts. That should give you an idea if the set was given Tier 2.

View attachment 697284

View attachment 697285

The fuel and temperature gauges look newer than the others.

View attachment 697286

.

 

[Bmxenbrett]

If your grounding the sensor wires on the back of the gauge and have 24v at the gauge and you get mo movement you have bad gauges.
My fuel gauge went dead from my trailer to its resting place. Towed it 300mi home and went dead in 50ft. Stewart werner makes a good replacement gauge for the fuel.

 

[csheath]

I found my existing gauge has a connection problem inside on the ground. Cleaned all the connections and that didn't fix it but can twist the post the ground wires are on and it will start working.

 

[Guyfang]

Typical. This often happens when some one at some time tightened the not on the post too far, and the post turned instead.