1981 Merc Oil Pressure Gauge

[62cruiserinc]

Hi:
I have a 1981 Sea Ray with a Merc 260 and alpha drive.

The oil pressure gauge has been pegged at max for a while (even when shut off), so I need to replace it. It looks like the original gauge from 1981. The oil pressure sending unit is a single wire connection.

I am assuming I need to replace the gauge and the sending unit so they match up properly?

Is there an OEM-type replacement gauge available that works with the current sending unit?

Thanks
Steve

 

[Bt Doctur]

No ,usually just the sender

 

[Scott Danforth]

usually the sender is bad or the wire is pinched / grounded

 

[62cruiserinc]

I checked the voltage with the engine idling and there was about 4 volts at the sender and at the gauge. The gauge is always pegged at 80psi, even with engine and power off.

Steve

 

[GA_Boater]

Check the signal voltage on the gauge with the engine off and keep the meter connected. Start it up and the voltage should change.

No voltage change - Bad sender or wiring.
Voltage changes - Bad gauge.

 

[62cruiserinc]

I will check the voltage with the engine off.

If the gauge is bad, will any single-wire oil pressure gauge work with my existing sending unit?

There are also some "marine oil pressure gauges" available. Does this mean they are weatherproof or are the voltages different than an automotive oil pressure gauge?

Thanks
Steve