1989 Johnson 40hp power loss

[captain klemm]

Have a problem with my 40 hp Johnson , Boat sat for 2 years, cleaned fuel tank, put boat in the water and started right up. It is the oil injected model. boat only has about 15 to 20 percent of it's power. Not sure where to start It starts and idles just fine but when you give it full throttle it doesn't have much power.
Any suggestions?

thanks

 

[Sherman]

Re: 1989 Johnson 40hp power loss

Sounds like the high speed jet in the carb is plugged. Good Idea to pull carb and clean and install a new kit. They are cheap.

 

[kjdunne]

Re: 1989 Johnson 40hp power loss

Ditto on the carbs. Same situation occured with my '89 40 hp. Sat for 2 yrs, started fine but would not run over 2K rpm. Follow the manual for rebuild of carbs, and you'll be back in business.

 

[tashasdaddy]

Re: 1989 Johnson 40hp power loss

sitting 2 years it needs more than carb cleaning. it will need a water pump service. if still using the Vro, it will have to be primed, to make sure you have fuel/oil mix to the carbs, just priming the fuel, only delivers gas, no oil.

http://forums.iboats.com/showthread.php?t=158086

http://forums.iboats.com/showthread.php?t=244013

 

[captain klemm]

Re: 1989 Johnson 40hp power loss

Hey! thanks for the quick diagnosis . I just found this site today and the response to my boat problems has been outstanding. It's great to know there are so many helpful folks out there. We have had this boat for over 12 years with no engine problems until now. Sounds like a easy fix

thanks again!