Lehman/American Diesel 136 Pressure/Temp Sensor Wiring

[DBG8492]

So I'm trying to figure out the sensor wiring for the oil pressure - see pic below.

There are four wires hanging there disconnected.

One Solid black 12 ga - goes to starter ground
One Black w/green tracer 14 ga - goes into wiring bundle
Two Tan w/red tracer - goes into wiring bundle

NOTE: Pay no attention to those connectors - I added them trying to figure it out. When I found them, the connectors were all broken.

You can see the two sensors there. I'm assuming that the one with two poles is the sending unit for the pressure, and the single pole is the alarm circuit.

I checked the back of the oil pressure gauge and the wires are black w/green tracer.

The second pic is from a VDO diagram on their website, I am assuming that my sensor is probably Illus. 2 - which would mean the floating ground to the starter goes to one pole and the black w/green tracer goes to the other.

However, I'm at a loss for the other two wires and what runs the alarm circuit. The alarm doesn't work by the way - when I turn on the key, there is no tone.

Does what I'm saying make sense? Anyone else lucky enough to have this setup with this color combination and can shed some light?

Thanks in advance.

 

[Comodave]

Contact American Diesel. Brian can probably tell you immediately.

 

[DBG8492]

Well, I figured it out by replacing the original senders with ones I ordered from Brian at American Diesel...

The new pressure gauge sensor is a single pole dual station that grounds to the engine block, so oil pressure is now available again at both stations.

With the ignition on, I tested both of the tan wires on the sensor and one of them caused the buzzer to go off.

So now I have oil pressure at the gauges and an alarm for low pressure.

Test run of the engine shows a little over 40 PSI at idle.

However, I got a "low voltage" alert while she was running. Gauge says the alternator is only putting out 12.5 volts. Not sure what happened...

I replaced the belts with new and tightened them up, but still 12.5.

I have a spare alternator from the previous owner - tag says it was rebuilt and bench tested in Nov of 2010...:lol:

Gonna make the swap and see what happens.

Someone needs to turn the damned thermostat down out here. For Christ's sake...

 

[DBG8492]

Spare alternator fixed the issue. We're back over 14v and no more alarms. ProIsiCharge is charging all banks.

Still no temp gauge so I will be using the laser thermometer I suppose...

 

[OBXSkipper]

Good to hear, now if You could start workin on the heatwave here in NC, it would be greatly appreciated. Engine rooms in this heat are unbearable . Good Luck

 

[DBG8492]

Good to hear, now if You could start workin on the heatwave here in NC, it would be greatly appreciated. Engine rooms in this heat are unbearable . Good Luck

It's insane. Seriously.

I haven't sweat this much since I was deployed.

We have two 8K BTU room AC units going non stop and they barely put a dent in it. And they don't even reach the engine room...

I am going to be happy to be underway hanging out in the pilothouse tomorrow.