1988 yamaha pro50LG oil consumption

[Collinsje308]

Hey Guys,

So i have a 1988 yamaha pro50LG oil injected two stroke carbonated outboard. And I can seem to find the answer to this question any where on the internet. How much 2 stroke oil should my motor be using? As it doesn't seem to be using hardly any at all. Now this motor just has the oil tank under the cowl.

Thanks for any and all help!

[99yam40]

depends on how you run it.
high RPM should use around 50:1 ratio (gas to oil)
low RPM is a lot less

[boscoe99]

As noted, up to 50:1 at wide open throttle at 5500 RPM. Down to 200:1 at idle.

Oil consumption is a function of throttle opening and RPM.

[Collinsje308]

Thanks for the replies guys!!

I've ran about 4-6 gallons of gas through it mostly at low speed. Except for 4 2 mile runs at wide open and the oil level in my tank hasn't moved at all. I think there is a problem with the oiling system.

Is it a problem to just run mixed gas in the gas tank? Or do I have to do something to take to oiling system out. Or do you guys have any other ideas.

Thanks again.

[99yam40]

service manual should have a procedure for testing out put

[boscoe99]

My idea is that you don't have a problem. Based on your runs I doubt that enough oil has been used such that it can be seen in the tank.

If you are a nervous nellie, connect a three gallon tank of premix gasoline to the motor. Disconnect the oil hoses from the oil pump. Start and run the motor. You should see some oil slowly oozing from the oil lines. That will tell you that the pump is working. Oil is gravity fed to the oil pump. Gravity is usually pretty reliable.

People confuse the Yamaha oiling system with the Evinrude/Johnson oiling systems.

[Collinsje308]

Thanks for the help guys!!!! I think i am going to try boscoe99's suggestion. just to make sure. As i dont completly trust this motor, with all the other issues i have had to fix and money i have spent on this motor since i bought it.

Thanks agian.

[99yam40]

also you can mark the tank level so you can tell if it is dropping some while running on a premix.
there should be a test procedure in manual that tells how much you should get out of a line while running at some RPM, but measuring that could be hard to do

[Collinsje308]

Hey guys,

I ended up running a separate pre mix gas can. i ran about 12-14 gallons though it and the oil level in the tank went down quite a bit. So my worries are put to bed. Thanks for all your help.

Thanks,