1988 25 Horsepower Johnson

[CDEAN1469]

Motor Wont Run At Full Throttle Idles Just Fine Starts Fine I Have Rebuilt The Carb Replaced All The Fuel Lines Replaced The Tank Still Wont Run The Only Way It Will Run Full Throttle Is To Put Your Hand In Front Of Carb What Could Possibly Be The Problem Too Little Fuel If Thats The Case How Do I Fix It

 

[jonesg]

Re: 1988 25 Horsepower Johnson

Motor Wont Run At Full Throttle Idles Just Fine Starts Fine I Have Rebuilt The Carb Replaced All The Fuel Lines Replaced The Tank Still Wont Run The Only Way It Will Run Full Throttle Is To Put Your Hand In Front Of Carb What Could Possibly Be The Problem Too Little Fuel If Thats The Case How Do I Fix It

rebuild the carb properly, something was missed,
maybe the float is upside down.
Maybe the jets got swapped around, low speed and hi speed .
Its easy to make a mistake.

 

[F_R]

Re: 1988 25 Horsepower Johnson

rebuild the carb properly, something was missed,
maybe the float is upside down.
Maybe the jets got swapped around, low speed and hi speed .
Its easy to make a mistake.

Betcha the high speed jet (orifice plug) is dirty or gummed up. Did you check it? It is a precision orifice and has to be absolutely clean with not a trace of any varnish in it. And don't be reaming it out....too big is just as bad as too small.

 

[tashasdaddy]

Re: 1988 25 Horsepower Johnson

read the TOP SECRET FILE, top of this forum.

 

[CDEAN1469]

Re: 1988 25 Horsepower Johnson

top secret file

 

[CDEAN1469]

Re: 1988 25 Horsepower Johnson

I took my time with the carburetor im almost 100 percent that it was done right what gets me is that when you restrict the carb with some thing it runs like a champ

 

[CDEAN1469]

Re: 1988 25 Horsepower Johnson

I took my time with the carburetor im almost 100 percent that it was done right what gets me is that when you restrict the carb with some thing it runs like a champ

 

[CDEAN1469]

Re: 1988 25 Horsepower Johnson

top secret file ?cant find that

 

[quackaddict1]

Re: 1988 25 Horsepower Johnson

I had trouble like this on a 95 28SPL, the cause was a leaking intake gasket, making the fuel air mixture to lean to run at WOT. You can test by taking carb cleaner and spraying around the gasket while at idle. Try to prevent any of the spray getting into the intake though. If you hit a spot and the motor dies while you spray there, you have found your leak. The carb cleaner will be sucked in through the leak and will make the mixture so rich it will die.

Any leak in a two stroke will make the motor not run right. Crank seals, intake seals, exhaust seals all could be problematic. Good news is if its just an intake seal they are fairly easy to replace by yourself and cheap for the parts. Just go slow and don't mess up the reed valves.

 

[CDEAN1469]

Re: 1988 25 Horsepower Johnson

I had trouble like this on a 95 28SPL, the cause was a leaking intake gasket, making the fuel air mixture to lean to run at WOT. You can test by taking carb cleaner and spraying around the gasket while at idle. Try to prevent any of the spray getting into the intake though. If you hit a spot and the motor dies while you spray there, you have found your leak. The carb cleaner will be sucked in through the leak and will make the mixture so rich it will die.

Any leak in a two stroke will make the motor not run right. Crank seals, intake seals, exhaust seals all could be problematic. Good news is if its just an intake seal they are fairly easy to replace by yourself and cheap for the parts. Just go slow and don't mess up the reed valves.

Thanks i will try that