Johnson 115 idle problem

[cheyanne]

Hello to all.
I have just taken on a nice boat project of a mako 19 (nearly finished)
It has a johnson 115.

We had starting issues and finally got it started, but the idle is really bad, basically it does not idle well at all.
Compression is good, as is the spark in all cylinders, but the left side runs cold, you can touch the head and feel nothing at all, the right side is very hot to the touch, this seems normal.
The plugs don't appear to be fouling up with oil they are wet and the fuel is getting there, but it just will not idle.

It has new carbs.

I would welcome any suggestions.

 

[emdsapmgr]

Re: Johnson 115 idle problem

You don't mention what year/model this engine is. Bombardier makes both a crossflow (out of production) and a loop-charged 115. Some are carbed engines, some direct injected. Would be helpful to know just what engine year you are dealing with.

 

[cheyanne]

Re: Johnson 115 idle problem

The serial number noted on the clamp is 190275 30ASI
This is the only number I can find.
This may be a 2001?
It is carb engine. The 2 carbs are brand new. Plugs are new, wet but not oily.
There is a red (what I believe to be the enrichment switch? This is manually operated). When I put this anti-clockwise the engine needs a lot of throttle just to run, when I turn it clockwise the engine idles a little better, but the left side cylinders stay cold, only the right side gets hot.

 

[bob johnson]

Re: Johnson 115 idle problem

normal is the head it hot but you can hold your hand on it for 2 seconds with out getting burned....you could check to see if there is a thermostat in the cool head.... it might have been taken out. other wise id say you have a mixture problem...the motor should have four carbs...

you could start by screwing the idle adjustment all the way in then backing out to th specs in the manual. then if you still have issues, you might need to rebuild the carbs..

bob

 

[metriccrescentwrench]

Re: Johnson 115 idle problem

The serial number noted on the clamp is 190275 30ASI
There is a red (what I believe to be the enrichment switch? This is manually operated). When I put this anti-clockwise the engine needs a lot of throttle just to run, when I turn it clockwise the engine idles a little better

The lever on your primer solenoid should be aligned with the solenoid body for normal operation. If you run the engine with it in the wrong position it'll be overly rich because raw fuel will be getting injected into the intakes, and it'll be the worst at idle (so I'm guessing it's in the proper position when you say it's clockwise).

but the left side cylinders stay cold, only the right side gets hot.

That could possibly be your entire problem.

The serial number noted on the clamp is 190275 30ASI

What's the model number? Look for something like J115SLESE .

 

[cheyanne]

Re: Johnson 115 idle problem

Thank you for the information and tips.
It turned out to be exactly what was thought in the thread replies. The idle screw was all the way to the left(anti-clockwise).
It is now in the correct position and runs nicely.
All I have to do now is replace the ignition switch as it would not switch off. What a game!
But all in all job done.

Thank you