Volvo Penta AQA 41A Oil Pressure Alarm

[Dill et Bound]

I was lucky enough to be able to use the boat last night, for a quick beer in Herm. I have been having a small problem with the Oil Alarm, that last night became really annoying.
I have noticed that after a short time running, going back on to tickover, the alarm would just beep a couple of times, Oil pressure good on gauge. Last couple of times out its got worse, soon as you go on tickover alarm goes off. Turn off ignition wait 2 seconds, restart engine alarm goes off, and stays off, till you go back on tickover after another run, comes back on. Loads of Oil, recent Oil Change, No Smoke, Well Ok a bit when you start up, but its a AQA41,No dirty transom though. And most important, good oil pressure on the gauge.
Anybody give me tips, Dash fault, or sender unit,
As the weather will be keeping me in port for a couple of days, and its too wet to mow the lawn, I could look at fixing it. Thanks..

 

[mm1]

It could be either but IMHO the gauges are the more reliable.
Regards mm1.so I would start with sender,however it could be a poor connection somewhere ,sorry to be vague but have had all three.

 

[superheat6k]

I had a duff oil alarm on one engine last year, and due to the sender location I couldn't get to it. Instead I found a spare tapping at the oil filter where I fitted a conventional gauge to confirm pressure was present.

Then I fitted one of these from RS components 398-6985 which has dedicated terminals for both sides of the switch, unlike he vast majority of automobile engine oil switches. This switch is also adjustable and I set it for 1.4 bar, but to do this you have to simulate the required pressure to check the setting.

 

[volvopaul]

You may find its a sticking relief valve that lowers the oil pressure to the cut in level for the switch to work.

This often happens when the revs drop to idle after a hard run when the oil is thin.

 

[Dill et Bound]

Thanks for the info chaps.. I am looking at the sticking relief valve, as I have checked wire connections, dash, and the sender must be working, It as ok last night on my return to my berth, but did play up earlier in the evening, when putting down the hook, Off to Poole on Sunday so will pop in to Trickett Marine pick up some parts on Monday morning.
Thanks again and lets hope this Azores high stays with us for a good while..

 

[volvopaul]

Thanks for the info chaps.. I am looking at the sticking relief valve, as I have checked wire connections, dash, and the sender must be working, It as ok last night on my return to my berth, but did play up earlier in the evening, when putting down the hook, Off to Poole on Sunday so will pop in to Trickett Marine pick up some parts on Monday morning.
Thanks again and lets hope this Azores high stays with us for a good while..

I doubt trickett will have the valves and springs, you will need a lot more than that to change the valves as its oil cooler and filter assembly off, depending on access you will also need the heat exchanger off to get at it.

 

[Dill et Bound]

I have good access, but it does look a little tight, I will check with them tomorrow, I am on the Ferry on Sunday anyway so if they hav nt got them, I will get the bits from somewhere else. Hope to catch up with Piratemark to have a look at his project as well whilst in UK, so will be driving all round South of England.. Thanks Paul