Mid-late 80's 120hp Johnson VRO

[saxrulez]

I just bought my first boat and it has a Johnson 120, although the PO didn't know the year of the motor. I'm in the process of restoring....well just about everything, but the engine ran great(test drove it for a bout 45 minutes). Is there anything in particular I should watch for on this engine?

It has been converted over to pre-mix.

 

[spingley]

Re: Mid-late 80's 120hp Johnson VRO

If you do not know the last time the water pump impeller was replaced, I would go ahead and replace it. I read somewhere that they should be replaced every 3 years because the rubber deteriorates, and you do not want to overheat the motor while on open water.

 

[jonesg]

Re: Mid-late 80's 120hp Johnson VRO

Water pump,
thermostats
gear oil ,(new seals on drain screws,)
check compression
plugs,
decarb cyl's with seafoam
read the faq Top Secret files at the top of the Johnson forum.

Unless you know the service history?

 

[kenmyfam]

Re: Mid-late 80's 120hp Johnson VRO

I just bought my first boat and it has a Johnson 120, although the PO didn't know the year of the motor. I'm in the process of restoring....well just about everything, but the engine ran great(test drove it for a bout 45 minutes). Is there anything in particular I should watch for on this engine?

It has been converted over to pre-mix.

Post your model number (port side of transom bracket) and let's see exactly what you have.
They are a great motor and you have been given great advice already. The top secret files will give you a wealth of knowledge.
Enjoy your motor.