"No Oil" Alarm Problems

[Saxe Point]

This problem is incredibly annoying and I'm hoping that some of you have suggestions for solutions. My 1996 90hp 2 stroke Johnson runs great. It is oil injected with the system known as VRO. However, sometimes the "no oil" horn goes off and the "no oil" light on the tach goes on. So I stop the motor and start it up. This never happens at idle, just when I am running at 2500 RPM or higher. But here's the strange thing, it doesn't happen all the time. I can run for hours and it won't happen. Then I'll go through a spell where it happens a lot, which is really annoying. It comes and goes. Oil is being consumed so it doesn't seem like the motor is being starved for oil. I checked the filter on the intake in the oil tank and it's pristine. Checked the oil hose for kinks and there aren't any. If it's a sensor, can I troubleshoot it? Where are the sensors? Any other ideas?

 

[trendsetter]

This problem is incredibly annoying and I'm hoping that some of you have suggestions for solutions. My 1996 90hp 2 stroke Johnson runs great. It is oil injected with the system known as VRO. However, sometimes the "no oil" horn goes off and the "no oil" light on the tach goes on. So I stop the motor and start it up. This never happens at idle, just when I am running at 2500 RPM or higher. But here's the strange thing, it doesn't happen all the time. I can run for hours and it won't happen. Then I'll go through a spell where it happens a lot, which is really annoying. It comes and goes. Oil is being consumed so it doesn't seem like the motor is being starved for oil. I checked the filter on the intake in the oil tank and it's pristine. Checked the oil hose for kinks and there aren't any. If it's a sensor, can I troubleshoot it? Where are the sensors? Any other ideas?

There are two sensors; one in the oil tank which measures the oil level and sounds the "low-oil" alarm and one on the back of the fuel pump which triggers the "no oil" alarm.

How low is the oil tank? Mine gives the low oil alarm at about 1/8th full. It's also possible that the oil pump diaphragm is getting worn and is not pumping enough giving the "no-oil" alarm. Or the sensor(s) could be faulty. These pumps are not cheap so the best option is usually to disable the oil injection and go to premix which is a very easy process. The drawback is then you have to premix the gas.

 

[Battle Bay]

Get rid of that VRO. Mix your fuel, way safer

 

[sly_karma]

By 1996 VRO had been around for more than a decade and was well sorted. If you disable it, you're back to 50:1 fuel at all times but the carbs are expecting the VRO to deliver 100:1 fuel at idle, so plug fouling and rough idle is likely. Get hold of a factory manual and go through the troubleshooting steps. False alarms are annoying but it would be best to try to make the system work as designed.

 

[trendsetter]

By 1996 VRO had been around for more than a decade and was well sorted. If you disable it, you're back to 50:1 fuel at all times but the carbs are expecting the VRO to deliver 100:1 fuel at idle, so plug fouling and rough idle is likely. Get hold of a factory manual and go through the troubleshooting steps. False alarms are annoying but it would be best to try to make the system work as designed.

I've disabled the oil injection on half a dozen of these outboards over the years. It does not cause plugs to foul nor a rough idle. The engine will run exactly as it did with the injection enabled. It will just burn a small amount more oil.

 

[profisher]

I would check the sending unit in the oil tank to see if it is working as it should. If it was a Yami I could give you more detailed advice .

 

[sudsy]

Probly a defective controller, had a 92 merc with similar symptoms. I used a multimeter to test the sensors, take a resistance check of the two cables on your float switch, it should change from open ( high restance) to closed, ( no resistance) dependsnt if the switch is active ( full oil tank) or empty. Not sure how you test the other sensor your talking about, but they should connect to the controller which sends the warning alarm to trigger on....most are simple resistance checks for these type of sensors....if the sensors check out, then the controller is your problem....good luck!