Oil mix with an injected motor.

[N1265]

Hi guys,

I have a new to me 1989 40 hp Yamaha motor. It was suggested to me to pre mix my first tank of gas 50:1 until I was sure the oil injection system was working ( by seeing if the level in the tank dropped)

My question is :

Is this good advice ? would I have problems with running a 50:1 oil premix AND the injection unit ?

 

[99yam40]

Re: Oil mix with an injected motor.

It is very good advice.
No, over oiling will not hurt the motor, but it will smoke more than usual

The manual even calls for doing that while bleeding air out of system after sevicing and during testing the oil system

 

[axolotl]

Re: Oil mix with an injected motor.

Correct.
The manual even specifies that oil premixing should also be done when the engine is left unused for a few months.
However the manufacturer assumes that oil-premixing and oil-injection will be done for a limited amount of time.

 

[jeffersondodson561]

Re: Oil mix with an injected motor.

It is not a bad idea and will not hurt anything, only thing I have heard was using 50:1 during break in. As far as I am concerned Merc and Yamaha oil injections system are damn near bullet proof. It is the VRO (OMC) that has given all other oil injection systems a bad name. It states in their service manual that you should mark the tank any time the VRO is serviced or replaced. Merc and Yamaha oil injection systems are driven off a worm gear on the crankshaft (whenever the motor is turning oil pump is turning) where as the VRO oil injection is operated off of crank case pulses.

 

[N1265]

Re: Oil mix with an injected motor.

Many Thanks....

 

[Outsider]

Re: Oil mix with an injected motor.

Who suggested a pre-mix? If it was the previous owner ... :facepalm:

 

[Silvertip]

Re: Oil mix with an injected motor.

It is not a bad idea and will not hurt anything, only thing I have heard was using 50:1 during break in. As far as I am concerned Merc and Yamaha oil injections system are damn near bullet proof. It is the VRO (OMC) that has given all other oil injection systems a bad name. It states in their service manual that you should mark the tank any time the VRO is serviced or replaced. Merc and Yamaha oil injection systems are driven off a worm gear on the crankshaft (whenever the motor is turning oil pump is turning) where as the VRO oil injection is operated off of crank case pulses.

Mercury's "plastic" injection pump drive gear never goes bye-bye huh?? So much for bullet proof.

 

[jeffersondodson561]

Re: Oil mix with an injected motor.

Agree to disagree.