Johnson 140 v4, 1986...issue? or not?

Rscardina

Chief Petty Officer
Joined
May 3, 2010
Messages
513
I have a 1986 Johnson 140 v4, i did a bunch of work on it last year with the help of a factory manual and a ton of help from all of the members here!

This years issue: I started he boat up last week to get her ready for the season. I charged both of my batteries, cleaned all electrical connections. I changed fuel/water sperator. Once primed she starts up and cough a bit, but once warmed up she seems to idle ok with minimal issue. I started it again this weekend (i try and start once awek if not in use to keep batteries going).. I thought i would let her run for a bit but for some reason after 20 min of idling she died..(this is outside on the trailer with muffs). I primed again (one squeeze and she was tight) and tried to start again.. she would just spin but not fire.. I waited a few minutes and tried again..this time if I advanced the throttle sligtly she would catch..
My question is : Can these motors flood themselves when idling because its not running at high rpms? Meaning that you are not supposed to troll per say with outboards?..

FYI- I rebuilt carbs last year, new power pack, 4 new plugs, 4 new coils..

Any suggestions or tips to these engines?:confused:
 

hidef

Lieutenant
Joined
Aug 22, 2009
Messages
1,465
Re: Johnson 140 v4, 1986...issue? or not?

My old 140 never liked to idle very long. Once she was warmed up so she wanted run. If she idled to long she would foul the spark plugs and I didn't use the surface gaps.
 

emoney

Commander
Joined
Jul 19, 2010
Messages
2,551
Re: Johnson 140 v4, 1986...issue? or not?

^that's a good point. Did you check the plugs? ((sticking my nose in because I've got it's older sister, and although I haven't idled
it long enough to encounter this, since I just picked it up, it's good info to know))
 

hidef

Lieutenant
Joined
Aug 22, 2009
Messages
1,465
Re: Johnson 140 v4, 1986...issue? or not?

The old cross flows 140s were designed to do one thing and one thing only and that was to run fast. Big carbs and a big exhaust and nothing else on the water sounds like a 140 at full throttle.
 

DargelJohn

Petty Officer 1st Class
Joined
Feb 14, 2010
Messages
337
Re: Johnson 140 v4, 1986...issue? or not?

This motor would be a Looper.
 

hidef

Lieutenant
Joined
Aug 22, 2009
Messages
1,465
Re: Johnson 140 v4, 1986...issue? or not?

My Bad forgot they changed to the Looper in 85
 

Rscardina

Chief Petty Officer
Joined
May 3, 2010
Messages
513
Re: Johnson 140 v4, 1986...issue? or not?

So is the feeling here that this engine..looper.. is in fact the same way in that it wants to run and run fast> I'll check plugs this afternoon to be certain they are good and clean.

My assumption was fuel, spark and compression..if all that is there then she should run till she is out of gas.. is this a good asumption? or is this engine have its quirks about idle..?

This motor is strong from what I have heard..well built.

Thanks for the help!
 

DargelJohn

Petty Officer 1st Class
Joined
Feb 14, 2010
Messages
337
Re: Johnson 140 v4, 1986...issue? or not?

They do tend to "load up" when left idling for a while. All 2 cycle engines need to be rev'd to burn excess fuel in the crankcase. Take it out and "run it like you stole it" and see if that makes a difference.
 
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