Johnson 120 What year?

[pistol8]

I bought a 1988 Ranger 390v with what is supposed to be a 1994 Johnson 120. I can't seem to find any numbers on this motor. I have also been told by a marina that it is a 140 that someone replaced the engine cover with a 120 cover because the cover was damaged. This motor looks almost new. It runs great and pushs this Ranger at 60mph by my garmin gps. Also theres no vro pump on this motor. My problem is sometimes it idles fine other times it dies at idle by it restarts very easy and will idle or sometimes not. I have had many boats and motors(mostly Suzuki's)but I'm real happy with this Johnson its good on fuel and I feel like I can trust it. I've been out to Naples reefs offshore and its great.(P.S. it's paid for)so I would like to know for sure what year it is and get some manuals and fix the idle issue. Any help would be great. Thanks Mike

 

[Gary H NC]

Re: Johnson 120 What year?

Try finding the model number on the port side of the engine bracket.
There should also be a round aluminum plug on top of the head that has numbers stamped on it.
Post what you find and you should get some replies.

BY THE WAY,WELCOME TO IBOATS!

 

[HighTrim]

Re: Johnson 120 What year?

Welcome to iboats

Im assuming you looked on the stern bracket for the id tag, that should contain the model number. Short of that, look for the welch plug, it is about the size of a quarter, and should be on the top rear of the motor.

Set the idle to 650-750 RPM under load in gear. That will be around 1100RPM while on muffs in the driveway.

argh, Gary ya beat me to it, sorry

 

[pistol8]

Re: Johnson 120 What year?

Well it's 10:30 and my son and I just looked and there is neither a plug on this motor or tag you got me maybe some visible way of telling? The module says loopercd4? Mike

 

[kenmyfam]

Re: Johnson 120 What year?

Well it's 10:30 and my son and I just looked and there is neither a plug on this motor or tag you got me maybe some visible way of telling? The module says loopercd4? Mike

The welch plug must be there. It is a silver plug and as stated above about quarter size. Once you spot it you will wonder how you ever missed it.

 

[pistol8]

Re: Johnson 120 What year?

Sorry I didn't get back sooner but ended up in the hospital for two days. Is it possible the welch plug could be under the power pac between the cylinders? Mike

 

[Dhadley]

Re: Johnson 120 What year?

Yes, the 1994 V4 loopers did not come with a VRO. They came with an OMS pump so you should still have the oil injection feature. The welch plug on that motor will not be on top but rather on a recess in the rear of the block over the exhaust cavity. That recess will be closer to the top of the back rather than closer to the bottom. The plug may have only the serieal number, it may say something like "RPH" and then 6 numbers. It may not be there at all.

An intermittent idle can be caused by several things. If there's any question at all about the carbs it'll be better to clean them. Could be an ignition related thing. Also look at what spark plugs are in it. Does it just die like you shut the key off or does it "spit and then die?