Won't Start <> 1988 28 Hp SPL Johnson

[sturdavj]

Good spark both top & bottom plugs.

Top cylinder is wet,(maybe to much/not sure?) bottom cylinder is dry air, no fuel mixture.

Before I pull the carb & intake any suggestions as to what may cause this problem

 

[JB]

Re: Won't Start <> 1988 28 Hp SPL Johnson

That engine should start and idle on one cylinder. The fault is not with just one cylinder.

I do not trust wet/dry for diagnosis. Go to the Engine FAQs Forum or the Top Secret File ^^ and do the "Outboard won't start" troubleshooting.

Let us know the results.

Good luck.

 

[sturdavj]

Re: Won't Start <> 1988 28 Hp SPL Johnson

Thanks I went down the list, I planned to check the float seat needle. But I am wondering could I have a problem with the leaf valves ?

While checking the top plug I was able to fire off the mixture as it left the cylinder, tried this with the bottom cylinder spark was strong however did not light off the mixture, nothing

I have what I believe to be a strong spark = 1/8 arc gap, appears more white than blue ?

 

[tashasdaddy]

Re: Won't Start <> 1988 28 Hp SPL Johnson

using adjustable spark tester, you should get a 3/8 to 1/2 inch blue arc. 7/16 if electric start.

 

[sturdavj]

Re: Won't Start <> 1988 28 Hp SPL Johnson

Went down the list, found some crap in the float valve seat.

It starts fine, but coughs/sputter ~ 10>15 Sec apart. I have ordered a spark gap tester, I?ll let you know what I find.

 

[Daviet]

Re: Won't Start <> 1988 28 Hp SPL Johnson

Did you overhaul the carb or just clean the needle and seat? Might still have trash in the rest of the carb circuts.

 

[sturdavj]

Re: Won't Start <> 1988 28 Hp SPL Johnson

I rebuilt the carb and ran it for a short time before I placed motor in storage. Pickled the motor and put it in storage.

The cough is slight, otherwise motor runs fairly smooth. I am not sure is this is normal for this motor?

 

[sturdavj]

Re: Won't Start <> 1988 28 Hp SPL Johnson

Spark tester arrived today,used it and the spark was bright blue and 7/16" long. This is a cool tool, glad I ordered one.

The motor is running better, time to list it for sale.

Thanks for the help

 

[northwoodslivin]

Re: Won't Start <> 1988 28 Hp SPL Johnson

I had the coughing you describe with my motor "mines an 89 20hp" as well. It took me a while to find what was causing it, but it was my old fuel lines, the ethanol in the gas today will eat those old lines. I would suggest replacing all your fuel lines with ethanol friendly lines and make sure when you clean your carb to pull the plugs! I never did this at first, but on the last time I did and found pieces of fuel line in there.

Good luck