Yamaha 115hp saltwater series oil alarm

[paulaus123]

Hello I have a 2011 115hp 2 stroke saltwater series outboard and my oil alarm keeps going off and lowering the engine RPM too 2000RPM,I think this is limp mode.

The alarm is sounding even though both oil reservoir's are full, when the alarm sounds I get all 3 bars flashing on my gauge (digital type) indicating that engine oil tank is empty but its full.

I have re terminated my battery leads and gone straight to the battery bypassing my battery switch.

The alarm will sometimes go off at different engine RPM's and other times it will operate fine. When the alarm does go off I return to neutral position and the alarm resets and I can power again.

I have measured the upper and lower resistance of the sensor in the engine oil tank and it is switching and when I empty the engine oil tank it will fill automatically from the remote tank and stop filling at the upper limit.

The supply to the sensor (red wire) was found to be around 10.2 VDC, is this normal?

Any advice would be much appreciated. Thanks

[Jason2tpa]

Check that your cranking battery is fully charged, terminals are clean. If it is, volt drop test at the starter. The 3 flashing indicators with alarm, limp mode (and full oil tanks)....this is most likely a power issue, not an oil issue.

[paulaus123]

Hi

I have re terminated all battery connections and cleaned battery terminals, have bypassed the battery isolator so cables are straight to battery.

Starting voltage is ok not dropping bellow 10.5VDC while engine is cranking.

I have also tried a new oil level sensor at the engine oil reservoir and this didn't fix the problem. The motor will run fine for a bit then start giving oil level alarms at varying engine rpm.

I have noticed that I can disconnect the oil level sensor at the engine oil reservoir and the motor will still run without any alarms, is this normal?

Is there any way of bypassing the oil alarm limp mode and just making sure that I keep the oil reservoir in the motor full?

Thanks

[99yam40]

if you can disconnect that float switch and it stops the alarm I would think that the switch has a problem or the wiring has a problem. watch the motor mounted tank to see where the level is when the alarm come in to see if it is not filling as it should when it alarms

[boscoe99]

There are connection points on the motor that can cause the low voltage alarm to appear. Poor connections at terminals and in the fuse holders for instance.

If you are willing to risk damaging/destroying the motor then certainly the alarm system can be over ridden.

[pstephens46]

There are connection points on the motor that can cause the low voltage alarm to appear. Poor connections at terminals and in the fuse holders for instance.

If you are willing to risk damaging/destroying the motor then certainly the alarm system can be over ridden.

You would think this is the case. According to OP, he tried a new oil level sensor with no change. He disconnected the wires to the same and oil alarm ceased. So an electrical issue other than sensor? Time to start tracing and testing connections and wires I would think. Is there a ground where there should not be.....

[boscoe99]

From Yamaha:

"The loosen battery warning activates when the CDI does not sense the presence of a battery in the circuit. This may be caused by a loose battery terminal on the battery or engine or a loose fuse causing a momentary break in the power supply. If this happens, the warning buzzer will sound and engine speed will reduce to about 2000 rpm. All three oil lights will flash."

I would inspect the fuse holders and also disconnect and reconnect every electrical connector several times to see if a problematic connector can be stumbled upon and made to work properly. To include the connectors to the switch up at the dash.