CAT 3126 Oil Pressure Sender

[BrianB]

My '97 Coach has a 3126 CAT and Allison 3060. After a long drive at freeway speeds when I slow down to city street speeds and then come to a stop at a light, sometimes I get either a Low Oil light or Low Oil Level light along with a warning chime. The light goes off and the warning chime stops after a few seconds. The gauge also reads low.

This has gone on since I have owned the coach. I have had three oil and filter changes so far. Oil testing shows all normal and no evidence of wear. Engine has only 45K miles. I called CAT some time ago and they said that it should not be a problem as the engine will stop if there is no oil pressure.

I think it might be a bad sending unit. I don't see where the sender is located on the passenger side or I just don't recognize it.

I am also going to install a mechanical gauge and see what that reads compared to the dash gauge.

I have never had a CEL come on and never had the engine de-rate or stop running.

Any ideas on what could be the problem and where the sender is located?

[wolfe10]

Good idea to double check with mechanical gauge.

Your chassis maker chose and installed the sender unit for the dash gauges. Check with them for it's location. But, yes, it is generally on the passenger's side of the engine.

And, as the Caterpillar tech told you, if oil pressure is too low, the engine will just quit running, as oil pressure is used to "power" the fuel injection.

[Janvlen]

I too have oil pressure indicater issues. My guage, no matter how cold it gets on start up, only reads to the middle of the dial on start up. As the engine warms up, it quickly falls to the "L" on the guage only coming up slightly if I rev the engine. I changed out the engine sensor, and it made no difference. The engine computer has never flashed an oil pressure or low oil warning. Next is change out the guage?

[wolfe10]

CJ,

First question is whether this is the Caterpillar supplied sender/gauge or the chassis maker supplied sender/gauge. Most coaches have both.