Oil Pressure Gauge and Alarm

[mcbridek]

Copied from Four WInns Forum:
I recently purchased 2000 Four Winns Horizon 180, 5.0 GL. 120 hours, runs great - At startup and running speed oil pressure guage reads in the middle of the guage (no numbers on the display). But when the boat is warmed up, and you stop bringing the engine RPM's to an idle, the pressure drops to just above the low pressure warning (red zone on gauge) and sometimes drops into the red and the alarm goes off. Anyone know the problem or fix ? I have heard it is a common problem with the sensor / gauge ???

 

[burp]

Re: Oil Pressure Gauge and Alarm

I'd have it looked at as it is 2 separate sensors. The oil pressure gauge gets it's input from the oil pressure sending unit. The audible alarm gets it's input from a separate oil pressure switch.

On the Volvo 5.7L engine they are mounted on the top, rear, port side of the engine near the distributor but are "T"ed off the same place. Maybe the configuration is the same for the 5.0L engine.

 

[Don S]

Re: Oil Pressure Gauge and Alarm

I would put a mechanical gauge on it and see what the actual pressure is when it's hot.
Here are the MINIMUM pressures you should see.

6 PSI at 1,000 RPM
18 PSI at 2,000 RPM
24 PSI at 4,000 RPM