I am working on a 150XR4 Black Max with oil injection. The initial complaint was that the warning beeper was going off on the customer in succession (continual beep beep beeping), indicating an oil injection issue. The initial key "on" beeps were heard (one long, two short), then nothing as it was running. I had started and ran this thing three separate times and thought the guy was nuts at first. He thought the oil injection pump or drive was out of it, as he explained that it didn't appear to be smoking like it used to. Then on the fourth start, the warning horn started beeping.
I pulled the drive coupler, and it was fine. Reoriented the magnet with the north pole side going in first. The next set of checks was the green wire to the warning module, which passed, the white wire to the sensor, which passed, then the blue/white wire, which has me puzzled. The Merc bible on this thing states that the blue/white should PEAK at around 5 volts, then drop off to around 1 volt after two revolutions of the crankshaft. My test showed that it stays at 4.96 volts and doesn't drop off at all. The book states that it should drop off, which makes sense to me. The only thing the book tells me is that if there is NO VOLTAGE, to change the sensor. It doesn't say anything about if the voltage doesn't drop back to 1 volt. So is that sensor bad, or should I be looking at the module? Also, after two revolutions, the buzzer started beeping again and the voltage was still at 4.96 volts. I want to be sure, cuz this sensor is almost 80 bucks and the warning module almost 200. I don't want to make an $80 mistake, or a $200 mistake whichever way you look at it. Also, when I removed the oil line that goes to the fuel line, the pump was working at idle (very small drop of oil every second or so), so I think the pump is safe. I also had a 50:1 tank feeding this thing when I initially started because I wanted to be certain it was getting a mix if the pump was bad, and it seemed to smoke almost excessively when the mix tank was hooked up.
Ripper
I pulled the drive coupler, and it was fine. Reoriented the magnet with the north pole side going in first. The next set of checks was the green wire to the warning module, which passed, the white wire to the sensor, which passed, then the blue/white wire, which has me puzzled. The Merc bible on this thing states that the blue/white should PEAK at around 5 volts, then drop off to around 1 volt after two revolutions of the crankshaft. My test showed that it stays at 4.96 volts and doesn't drop off at all. The book states that it should drop off, which makes sense to me. The only thing the book tells me is that if there is NO VOLTAGE, to change the sensor. It doesn't say anything about if the voltage doesn't drop back to 1 volt. So is that sensor bad, or should I be looking at the module? Also, after two revolutions, the buzzer started beeping again and the voltage was still at 4.96 volts. I want to be sure, cuz this sensor is almost 80 bucks and the warning module almost 200. I don't want to make an $80 mistake, or a $200 mistake whichever way you look at it. Also, when I removed the oil line that goes to the fuel line, the pump was working at idle (very small drop of oil every second or so), so I think the pump is safe. I also had a 50:1 tank feeding this thing when I initially started because I wanted to be certain it was getting a mix if the pump was bad, and it seemed to smoke almost excessively when the mix tank was hooked up.
Ripper
