1987 Johnson 140 hp problems

[johnsonjunk88]

Looking for help diagnosing a problem. The motor idles fine then revs to about 2,000 rpms and immediately drops back to idle then back to 2,000 rpms about 1/2 second between idle and revs (etc.) Thought it was a VRO problem, but after purchasing and installing a new 4 wire VRO pump, it is still doing the same thing. ran all the pre checks to make sure oil pump side is pumping oil, checked out OK. Noticed once it was running on the new pump it seemed to smoke alot more.

Please help, salmon are waiting.

 

[tashasdaddy]

Re: 1987 Johnson 140 hp problems

check throttle linkage, for play,

 

[kenmyfam]

Re: 1987 Johnson 140 hp problems

Sounds like play somewhere. What made you think it was the VRO ?????
New VRO gives 50:1 mix constantly I think ??? The older version give a varying oil mix depending on the RPM as far as I know. (But I could be wrong)

 

[Solittle]

Re: 1987 Johnson 140 hp problems

Whatever you do troubleshoot first, then buy the parts you need. First determine whether the problem is spark or fuel.

 

[johnsonjunk88]

Re: 1987 Johnson 140 hp problems

Checked for play in throttle linkage there was no play, there is spark when engine is running and idling fine but still smokes alot and smells to be burning very rich. Is it possible that the stator could be shutting down, killing half of the cylinders then correcting itself or when they go bad, do they just go bad? Also, do you think the carburators need to be rejeted to correct the smoking and rich burning problem?

 

[kenmyfam]

Re: 1987 Johnson 140 hp problems

What do your spark plugs look like ???
Did you change the VRO pump because it was smoking a lot ??? only you do not mention that in your first post.

 

[tashasdaddy]

Re: 1987 Johnson 140 hp problems

are you burning old gas?

 

[wilde1j]

Re: 1987 Johnson 140 hp problems

Have you moved the red primer lever? I did that to my J140 years ago, and it smoked to high heaven until I figured out what I'd done.

 

[johnsonjunk88]

Re: 1987 Johnson 140 hp problems

no i changed the VRO pump because i thought it was not getting enough oil or gas, due to the high revs when idling.