Running rich, why??

madolive3

Petty Officer 2nd Class
Joined
Sep 2, 2011
Messages
120
1978 Jonny 115 . I have cleaned and rebuilt the carbs, linked and synced, adjusted the timing and floats. It runs ok but I have the following symptoms. getting a large amount of fuel from the carbs when I choke. No fuel leaking when it's running though.
also getting fuel pouring from the lower carb after I shut the motor down.

Plugs are wet after running in the tank at various rpm below 2000.

Seems to load up and miss when idling.

I have the floats adjusted way past level as shown in the service manual so it should be running lean if anything.
Spark is blue and jumps a mile.
Could this be related to the Reed valves?
Thank you in advance....Bill
 

BonairII

Commander
Joined
Jun 7, 2011
Messages
2,727
Re: Running rich, why??

Probably not a great idea to run your floats toward the 'lean' side. Better rich than lean.

Have you replaced the needles/seats in your carbs? Excess fuel running out the carbs indicates that the needle/seat aren't stopping the flow of fuel when the bowl(s) are full.

Has the motor ever run correctly while you've owned it?

You absolutely sure that your running the correct(hot enough) spark plugs? I made that mistake earlier this year.
 

danoutbard

Petty Officer 3rd Class
Joined
Nov 18, 2011
Messages
87
Re: Running rich, why??

Probably not a great idea to run your floats toward the 'lean' side. Better rich than lean.

Have you replaced the needles/seats in your carbs? Excess fuel running out the carbs indicates that the needle/seat aren't stopping the flow of fuel when the bowl(s) are full.

Has the motor ever run correctly while you've owned it?

You absolutely sure that your running the correct(hot enough) spark plugs? I made that mistake earlier this year.

Totally agree on the needle/seat not stopping fuel when bowl are full...
 

madolive3

Petty Officer 2nd Class
Joined
Sep 2, 2011
Messages
120
Re: Running rich, why??

Yes, I did replace the needles and seats, complete rebuild. When I flip the carbs upside down I test the needles by blowing into the float bowls and the needles are seating. I brought this motor back to life after it sat for ten years. It actualy started before I rebuilt the carbs but had the same problem with the fuel pouring out of the carbs. Adjusting the floats helped.
I'm at wits end. Motor runs well, a little rough at idle in the tank, but out on the water it's been running pretty well.
I will check the plugs. No I have never been able to completely fix this problem.
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: Running rich, why??

How far of a gap will the spark actually jump ??
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,589
Re: Running rich, why??

Did you float test the floats? The floats may have pinholes and get heavy changing the adjustment height. That why I only install OEM kits as for about $4 more you get the everything including the float...
 

emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Re: Running rich, why??

Are you running the engine with the original floats? Are the floats in your carbs made from cork, or are they white plastic?
 

madolive3

Petty Officer 2nd Class
Joined
Sep 2, 2011
Messages
120
Re: Running rich, why??

The floats are black plastic and part of a rebuild kit. The spark jumps a good 3/4 of an inch.
I think I am going to take it to somebody who works on Johnson outboards for a living. I had it out yesterday and it wouldn't rev past 3200 Rs...Frustrated.
 
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