1996 130hp Johnson - Stalls at Normal Operating Temp

[Rassdog]

Hello,

I bought this outboard last year and it runs great except for the intermitted stalling at normal operating temperature at idle. I do not want to mess around with the timing (and all 9 or 10 steps in adjusting it!) to increase the idle speed set by the factory. I figure that there is no reason for this to be out of adjustment and when you start adjusting these things it may cause more problems. Hopefully I can avoid this as I'm just a backyard type of mechanic. I was thinking that it might be the ingnition system, maybe the wires or coils? I always run fresh plugs. This might also reduce the smoke a bit. I grew up around outboards and the Mercs my family has owned never seemed to smoke as much as this Johnson. Maybe it's running rich? Does anyone have any experience with this problem, or could suggest a solution? I want to do a little research before diving into ignition system replacement parts because they are probably very pricey. Thanks for your time!

 

[tashasdaddy]

Re: 1996 130hp Johnson - Stalls at Normal Operating Temp

do you have a tach? whats your idle rpm in gear. do you run seafoam of other cleaner/stabilizer, in you gas?

 

[Rassdog]

Re: 1996 130hp Johnson - Stalls at Normal Operating Temp

i have a tach and at N.O.T. the rpm's are about 600 - 700. I only run stabilizer when I winterize the boat and I decarbonize it once a year.

 

[Walker]

Re: 1996 130hp Johnson - Stalls at Normal Operating Temp

What do the plugs look like after idleing for a while??

 

[ezeke]

Re: 1996 130hp Johnson - Stalls at Normal Operating Temp

You may find that checking/replacing the recirculation check valves will help with both the smoking and the idle problem.

Using a synthetic oil will often help as well.

 

[Rassdog]

Re: 1996 130hp Johnson - Stalls at Normal Operating Temp

When I pulled the plugs they looked normal. Recirculation valves... I don't know about them; I'll have to research it. Are they difficult / expensive to service? Sounds like they are part of the exhaust system; Do I have to take the engine apart or are they just a bolt-on part? Regardless, thanks for the suggestions everyone.

 

[ezeke]

Re: 1996 130hp Johnson - Stalls at Normal Operating Temp

There are cylinder drains on the low points of each of your cylinders' lower bearing cavities leading to check valves. The check valves, when functioning, allow the flow of excess fuel and oil mixture in only one direction. The fuel/oil mixture is then added to the fresh fuel oil mix as it is drawn from the carburetor.

If they are blocked or stuck open they need to be cleaned and in some cases, replaced. I believe that new ones are around $15. each.

If the valves malfunction, the engine will idle roughly and will not reach maximum RPM. The unburned oil which should have been reduced will build up and cause excessive smoke at startup.

 

[Rassdog]

Re: 1996 130hp Johnson - Stalls at Normal Operating Temp

Thanks ezeke! That sounds logical and better yet, something I can do myself.