Yamaha Pro V 150 Newby w Questions

[Joe06351]

Hello everyone, I am happy to have found this forum. It looks to be active and have good information. I just bought a 1989 Checkmate with a Pro V 150 HP 2-stroke motor. The seller is married to the niece of a friend and I trust him, but he isn't mechanically knowledgeable. He told me it was a good running motor (and it is) but it had two problems.

He said it overheated at slow speeds and it tended to foul plugs. I got a Yamaha shop manual online and synchronized the oil injection pump with the throttle, finding it was giving too much oil, which could explain fouling plugs.

Took it out on the maiden voyage yesterday, and he motor pulled hard with a 22 pitch prop, which is good for water skiing, and ran well at speed for half an hour, which is when I decided to tempt fate and run slower (1500 rpm or so) back to the dock. After five minutes or so, I noticed a vibration, and this red light was on.

gage light.jpg

So two questions: 1. What does that red light mean, looks like low oil level, but both tanks are full. Is the green arrow what I should be looking at or the red square light?

2. I found an old thread that talked to the overheating problem and identified two parts that are often lost when rebuilding a water pump. I need to know part numbers for them and also what is a good pump rebuild kit.

Thanks in advance, I am looking forward to enjoying my new boat and this forum
Joe

ps here is my motor plate, I'm guessing it's original to the boat, 1989?

IMG_4525.JPG

[99yam40]

All I found was a PROV150LF,
so if that is the correct part diagram, here is a link to find the water pump kit
Yamaha Outboard 150HP OEM Parts Diagram for Repair Kit 2 | Boats.net

might check on the pressure control valve to see if it is stuck open dumping too much water at low RPM
#47
Yamaha Outboard 150HP OEM Parts Diagram for Crankcase - Cylinder | Boats.net


If those lights are warning of low oil level on motor, but full remote tank, you might need to see if the oil pump and inline filter at the remote tank are good, along with the float in motor tank is functioning properly

[brian3006]

Those are some darn fine motors. My dad has a 1990 model that is still running strong. ours too tends to be a little heavy on oil at idle, but better than too light. Just open it up regularly and it will be fine.

As for the impeller, go with Yamaha parts. it is a pretty simple job. Plenty of videos on youtube showing the process. Might be different motors, but the process is similar...


https://www.boats.net/catalog/yamaha.../lower-drive-1
https://www.boats.net/catalog/yamaha...prov150lf-1989.

I am not near his boat to look, but if memory serves me correctly, that red square is always there and/or it lights up when the oil level in the tank gets low. the arrow is over the green in your picwhich indicates oil level is fine. There are 2 oil tanks. one large one in the boat, and a smaller one on the port side of the motor. There is a filter inline under the tank mounted in the boat that sometimes gets clogged. When you first turn the key on, you should be able to hear the pump running as it pumps oil into the motor tank (if needed)

does your audible alarm work?
you should be able to test by pulling the sensor out of the motor-mounted oil tank. the arrows on the gauge should drop and the alarm should sound.