Fluctuating oil pressure

[killick]

The oil pressure readings on the gauge of the 12 hp westerbeke diesel engine in my boat has,all of a sudden, started fluctuating.When the engine is ideling the oil pressure is normal but as soon as the refs increase the needel starts quivering and drops to zero. The oil is changed on a regular basis and the engine has only done about 500 hours. Advice will be appreciated.

 

[Lakesailor]

Is it an electrical gauge or a mechanical one?

 

[killick]

Is it an electrical gauge or a mechanical one?

It is electrical

 

[30boat]

I'd say faulty gauge or sensor.Connect a machanical gauge to the engine and see if the pressure is good,which at 500 hours it should be.

 

[Sans Bateau]

It might be the gauge but then if the oil presure release valve was broken or weak or there was some internal leak you may get an indication of pressure at idle but as soon as the pressure increases the pressure bypasses and the resulting fall. Or it might just be the gauge.

 

[Lakesailor]

That's why I asked. Try a mechanical gauge first, or at least another sender and gauge.
It is just possible that it is a fault on the pressure relief valve, but unlikely.
It may also be a blocked strainer on the oil pick-up in the sump. But again not too likely.

 

[VicS]

Is there a separate oil pressure warning light. If so and it does not come on when the gauge reading falls to zero (but comes on OK before the engine is started) it suggests a faulty gauge or sensor

 

[rafiki_]

It is most likely the connector. I have had this with one of my engines, and cleaned up the sender unit connector.

 

[Billjratt]

I assume the oil level is correct - ie the proper dipstick is being used and the filter is the correct capacity/spec.
If not, fix that first and see what happens

 

[killick]

Thank you all for the advice. I am sure I will now be able to sort out the problem