INOP Oil Gauge

[slantflat]

Hey everyone.

1973 AMGeneral M35A2C, White muli-fuel engine. When the power switch is off, the oil gauge reads 0. When I turn the power switch on, the needle jumps to 60. That's before cranking. With the engine running it stays at 60. Actually pegged past 60.

What's a good place to start looking for trouble? I've read about the sender being for a 60lb gauge and having a 120lb gauge and vice versa. I'm not sure that applies here, since the erroneous reading is the same whether the engine is running or not. Is this a common problem amongst Deuces?

This brings up sub-questions. Is it better to have a 60- or 120lb gauge, or does it matter? What would it have had originally? Where is the sending unit located on the engine?

If this is all in a TM could you point me to it? The big TM I have doesn't cover oil gauges. Hm. Thanks everyone.

 

[SCSG-G4]

If the TM you have does not cover it, you don't have enough TM's. There is the -209 series (-10 through -34P), then the -361 series for the new format. Probably about 15 manuals in all. However, since the gauge pegs out I would suggest a short which could either be a bad sending unit, or a bad wire somewhere picking up full voltage, since the engine is not actually building pressure yet.

 

[Jeepsinker]

It's the sending unit.

 

[jbayer]

Mine did the same thing, found the sending unit connector was not completly on, circuit was open.

I only noticed it running, and thought I had great oil pressure, until I saw the same pressure with it off.

M35A2

 

[steelandcanvas]

Is it better to have a 60- or 120lb gauge, or does it matter? What would it have had originally? Where is the sending unit located on the engine?

The 0-60 PSI sending unit/gauge would be a little more precise over the 0-120 set up. Sending unit is on the passenger side, back of the block, above the starter. I agree with the others, sounds like a short somewhere. Be sure and download those TMs to become more familiar with your truck.