87 150 xr2 Mercury Oil Injection

[llyons]

I have an 87 Mercury 150 which recently started beeping while the engine was running. This started at the same time that a switch pack went out causing cylinders 2,4 and 6 to not fire properly.

I changed both switch packs and the motor is now firing on all 6 but the oil alarm is still beeping.

I checked the voltage on the oil module's white wire and it was 11.3 (low). The Battery voltage to the oil module is 12.5.. Both of these measurements using the same engine ground.

I tested the oil pump sensor with wires connected and spark plugs out, checking the voltage from the blue-white wire to ground. The voltage was 4.5vdc.

I rotated the engine several full revolutions and I never noticed the voltage drop to approx. 1vdc every 2 revolutions. The voltage stayed 4.5vdc the entire time.

I do know the​

pump is pumping oil since I can see it in the clear tube going down to the oil gas mixing block.

Does this sound like a bad oil pump sensor or oil alarm?​

Thanks in advance.

 

[llyons]

Hi,

We have a measurement on the oil pump sensor that says.. measure the blue white wire to ground and you should have 5vdc +- 1vdc. Also every 2 rotations of the motor, this voltage should drop to less than 1vdc.

in my instance, I have 4.75 vdc constant. There is NO DROP every 2 revolutions. The white wire to sensor has 11.7vdc

Is this indicative of a oil pump sensor problem?

thanks in advance

 

[llyons]

oil pump sensor check mercury oil injection

Hi,

We have a measurement on the oil pump sensor that says.. measure the blue white wire to ground and you should have 5vdc +- 1vdc. Also every 2 rotations of the motor, this voltage should drop to less than 1vdc.

in my instance, I have 4.75 vdc constant. There is NO DROP every 2 revolutions. The white wire to sensor has 11.7vdc

Is this indicative of a oil pump sensor problem?

thanks in advance

 

[racerone]

Have you checked to see if the oil pump is turning ?