I have a 1991 150 XR-4. It has the warning horn going off. It is a solid tone and the manual says that it is the oil injection system. I have checked all the manual recommendations and no joy.

I have replaced several lines from the oil pump, engine oil tank, and various others that looked bad. I have bled the oil pump and checked it for proper alignment with the alignment marks. I have also taken off the oil pump and inspected the drive shaft, bushing, and grommet. All look good with no signs of damage or wear.

The only time the warning is not sounding is when it is cold. However, that does not last long. All gauges read normal. Water pressure is good. Head temp never gets over half. I have disconnected the wires coming from the warning module and that cuts it off obviously.

Should I spend the money on a new oil pump and rotation sensor? Or is there something that I am missing?

Thanks in advance!

A solid tone is overheat,rapid beeps is oil. Check your tan wires from cylinder heads as you may have a defective sender or module...

How bout it chunky? Got the same motor doin the same thing. Wonderin what you found out.

My apologies on the tone. It does have the rapid beeps. I checked it again this weekend and verified it was the rapid and not the solid tone.

It had been a long time since I ran the motor in fear that it is not getting the right amount of oil. I certainly don't want to rebuild the PH. Far more expensive than getting this warning figured out.

So my original question is the same just that I have the rapid beeps vice solid tone.

Thanks!

I did however check the temp warning system and every thing checks out good. The motor is old so I did change the thermostats (pretty cheap to do) and read out the wiring. All within specs.

Rapid beeps is oil problem ie: module defective,oil gear on crank,pump not turning do to rotational sensor siezed in block(ethanol)