Oil alarm

[steplift20]

I'm mad, went down to go fishing. And this happened
Started her up,perfect
Drove her around ,no problems
Then after about a hour. I started her and the oil alarm
Went off.
Shut her down started her. Oil alarm went off ,so I took her back on land and and loosened the oil cap on the motor and it was pumping it into the oil resivoure ,so no issue with the pump
I did replace the cap/sending unit about three years ago.
What advice do you have for me? I'm going to go to my boat this week and check the cap/sending unit. After that I'm lost. Thanks for any replys

[spareparts]

Mercury?

[steplift20]

Yes spare, 1988 150 Mercury blackmax.
I know how to check the oil cap using a multimeter ,I'm just a hour away now from my boat and I did replace it about 3 years ago
The oil pump motion sensor. I do have my old one cause I did replace that too a long time ago, can you bench test the motion sensor? From what I see. The oil cap tells you if you have low oil
The motion sensor. Monitors the internal gear. So there are only too things left in case they check out good
The warning module. And the internal gear. But I'm not jumping to conclusions yet. If it's anyone of the last two I mentioned. Than I'm screwed. Just have to convert it to me mixing oil and gas but I don't know how to do that.

[steplift20]

One thing I forgot to mention, when you turn the key on it beeps than stops ( like it's supposed to do) then as soon as you start the engine it. Starts to beep with no delay. Just wanted to mention that.

[spareparts]

most likely the oil gear. You can check for voltage coming from oil pump sensor while the engine is running. If you aren't making any voltage, pull the oil pump, coupler and gear, shine a light in there and see if you see the gear. I've seen a bad sensor, a stripped coupler, and most of the time, stripped gear. Mix up a small tank of premix to run teh engine off of while testing

[steplift20]

Thanks spare,I will do that and let you know the results, but I really hope it's the cap.

[phatdaddy]

I used to verify my pump was working by running the engine on a small tank of premix. Then disconnect the oil line coming from pump and measure how much oil was coming out. Can t remember how much I t is supposed to be, maybe spare knows. Like 2 oz per minute at 1000 rpm

[steplift20]

What I did was loosen the oil cap on the motor and oil was pumping into the top tank. So I know that's working.

[spareparts]

What I did was loosen the oil cap on the motor and oil was pumping into the top tank. So I know that's working.

that tells you the pulse tube to the tank in the boat is working, it fills the reservoir on the engine that gravity feeds the pump on the engine. To test further, with the engine running, take teh hose off the outlet side of eth oil pump and see if its pumping oil, you can pop the oil control linkage off and push teh lever to full and it will pump a fair amount. With the linkage hooked up at idle, its hard to tell if its pumping or its just gravity feeding

[steplift20]

Spare? Is there a way to test the motion sensor? The sensor that monitors the internal oil gear. It's a small plastic fitting that has three wires a ground and two that probably ( I'm not sure) that go to the alarm module, I have replaced it a long time ago and kept the old one, the old one is good I just replaced it cause I was having a issue with loosing power to a switch box and it was setting off the alarm

[spareparts]

the senor is a me coil wrapped in copper, the shaft adaptor has a magnet in it, when a magnet passes a metal coil, it should produce voltage. IIRC, its AC. I've got a DVA adaptor that will give me specific voltage, but seeing as how the module is looking for any voltage, just compare from engine running to engine off

[steplift20]

Spare, I'm going to my boat today,I will let you know how I make out. Do you want to meet me in Atlantic highlands New Jersey today? I wish you were in nj but also I wish I was in SC . Wish me luck.

[steplift20]

I just came from my boat, checked the cap. Checked good
Replaced the oil motion sensor with a old one I kept that was good and alarm still sounded
I'm thinking the oil module? The only thing is it's expensive and I want to be sure,is there a way to check the module? If not then I'm hoping yo have to chance it
The only thing that might give you a clue I that when you turn the key it beeps three times like it should but as soon as it starts it beeps imidiately. No delay at all I hate to spend. All that money if I don't need it but if I need it then I would love to spend it. Thanks for any insight to this problem.

[steplift20]

My last question on the oil alarm.
If I disconnect the leads going to my motion sensor and oil cap float and the alarm keeps beeping does that mean the box monitor is no good?
Or will it do the opposite. .?

[spareparts]

its looking for a signal from the sensor

[steplift20]

Please bare with me, the oil pump/gear sensor has three wires,one is the ground and the other two are for something. What I would like to know is if I disconnect the two wires and hook it to a multimeter ( leaving the ground alone and hooked up) should I get voltage reading from the two wires? If it's working of course as the magnet turns internally.

[spareparts]

yes

[steplift20]

Spare thanks for taking the time to help me,I'm not good with electric but the multimeter question you answered for me is going to be a great help. That is what I'm going to do if I get no reading than its the motion sensor or the internal gear if I do get a reading than I'm going to replace the low oil and temp warning module. I found one on eBay ( new) for $260.00 that's the cheapest I found. Your a great help spare and really appriciate it. Thanks,

[spareparts]

make sure that thing is spinning before ordering the module

[steplift20]

I will spare,thanks.