Johnson 25 Stalling

[johnlark]

I could use some help. Recently bought a Carolina Skiff with a Johnson 25, 1986 vintage. First problemn was probably my fault, filled gas tank which had about a gallon of gas without dumping year old fuel.
Motor started right up, idled, but after about 10 minutes lost power and died. Couldn't get it restarted.
Suspected fuel, so dumped the tank, refilled, cleaned carb out, flushed it with good gas, changed the spark plugs, checked line bulb, definately getting fuel to carb, and checked and cleaned the fuel filter.
Engine now starts everytime... but even letting it run to warm for 20-30 minutes have to keep priming (push in key) to keep it running or it dies after a couple minutes.
Starts everytime, and can run the motor, but only with regular prime or it will loose power and die.
Fuel pump seems to work ok, but is that the problem or ???
Appreciate any help you can offer.

[F_R]

Remove the plug in the bottom/front of the carburetor and look for any evidence of gum or varnish in there. The main jet orfice is down deep in that hole and since that is the very bottom of the carb it is where the last dregs of fuel lay and turn to gum. If you see any evidence of gum at all, the carb needs to come apart and cleaned and a kit installed. It needs to be absolutely squeeky, shiney clean in there. Anything less and it will starve out and require constant priming to keep it running.

It takes a special screwdriver to get the main jet out, but it isn't actually necessary to remove it if you soak the whole bowl in carb cleaner and blow it out.

[mikesea]

yep,your problem is in the carb.The passages in the carb including the jets are likely to be gummed up.remove the carb and pull it apart. Its not a complicated item,springs arent going to jump out at ya or anything like that.Its best to let it sit in a carb cleaner.But I have used OMC carbon guard,thoroughly soaking the carb ,it breaks the varnish and crud down,after letting it sit for a couple hours a soapy warm water bath and hit it with a garden hose to rinse.Buy a spray can of carb cleaner at NAPA or any auto store and blow through all the passages using the little straw that comes with the can ,be sure the float needle is clean and goes up and down ok before putting the bowl back on.make sure all the old gas has been flushed from the rest of the lines and filter.

[ezeke]

When you have been doing this work, where is the fuel tank in relationship to the engine? If it is sitting on the ground, try raising it.

The fuel pump basically just gets the fuel to the float bowl and keeps it full, and gravity can do that if the tank is higher than the carburetor.

[johnlark]

Thanks for the help, I thought flushing the carb and being sure it was getting gas was sufficient, but definately didn't remove it to jet. Will remove as suggested and soak...
The tank is on the skiff floor, after cleaning if still any problem, to see if problem at the pump, I'll try raising it and see if that works.
Thanks again for the help.
John