Johnson 120

[AngryChair]

Hello

I just purchased a 1990 Cajun bass boat with a Johnson 120 VRO. This is the first boat I have owned. Model: J120TLASB Serial: G02541626. I have few questions about this motor. Thanks for any information.

What should the rpm's be at wot?
Should I add a fuel treatment in the tank, like stabil or some kind of decarb?
The previous owner disconnected the vro, should the oil be mixed 50:1?
If there is any other information you might have about this motor let me know.

Thanks



Modified by AngryChair at 8:52 PM 3/5/2010

[J E R E M Y]

good solid engines, that engine block and design have been built for many years.

i dont know of your wot rpms, but one of the other gurues will be able yo help with that.

i put the marine stai-bil in every tank of fuel in my boat to help with the ethanol issue. i also add BRP's carbon guard to every tank.

make sure that you mix your fuel/oil at 50:1. thats a pint of oil to every 6 gallons
and you should be good to go.

did you have a compression check done on the engine before you bought it and did the engine check out at a shop. if not i would recommend you to go have it done.

jeremy

[noelm]

very powerful engine in their day, I would get the VRO updated to the later system and fit it back on the motor, make sure max RPM with a "normal" load will be at least 5,500, but a bit more would be nice for that engine, remember just because you can turn 5,800 RPM, does not mean you have to run it there all day (but you could) you just need to make sure it can get there, 50:1 is the correct mix for that motor

[Bassmeister]

Am I the only one catching the model # not being right? Could that be A J120LESB instead of J120LASB?? I'll agree with updating the VRO and runniing that instead of premixing. JMHO

[AngryChair]

That is the model number printed on the motor. (J120TLASB)

Would hooking the VRO back up be something I could do, or should a marine shop do that?

I have not found an oil tank. Their are two fuel tanks. A twenty gallon tank under the seats and a twelve gallon tank in the bilge compartment. Could the small tank be an oil tank converted to a fuel tank?

On the engine controls under the key there is a knob that turns. When turned all the way to the right the engine will not go above 3000 rpms. When turned to the left engine revs fine. I was wondering what this is.

Thanks

[AngryChair]

After some searching, I think the knob is tension for the throttle cable. Is that correct? What is the purpose of it? I am new to boating so any info would be heplful. Thanks.

[ChampioNman]

Run it as it is, you would have to install a new oil tank etc. Yes that is a tension (friction) control knob. It is kind of like cruise control for your motor. Your model number is correct.