1995 40 hp force not RPM`ing under a load 8 MPH max

[gjess]

I just picked this boat up, engine starts up very good idles smooth, sound good. tach is non-op so cant give any RMP value . engine rev`s up running in a bucket good. I did not take to max RPM I know better . on the lake under a load I get 8 MPH and guessing @ 2000-2500 RPM max. compression both cylinder is 120 & and; 121 . fuel bulb is firm always, throttle opens fully. checking the stator red- red/white wires resistance is 8300 ohm`s spec in my manual is 6700-7600 , blue & blue/white 97. the trigger is 830 . I was expecting to find the hi speed shorted question is will the low speed spec cause this complaint ? engine serial # 0E124333. any ides ?

 

[ondarvr]

The primer bulb should not be firm when the motor is running, it will be soft.

​Have you checked for spark with a tester when it's in the water and under a load.

​Have you cleaned the carbs

 

[gm280]

gjess, when you are riving it up under load, have you checked to make sure both cylinders are firing? In the water when you riv up the throttle, pull each spark plug wire off one at a time and see if the engine changes RPMs. If it does that cylinder is firing and okay. If it doesn't change RPMs you have a dead cylinder and that is your problem. Let us know what you find out. JMHO

 

[gjess]

thanks for the ideas I`ll pull the carb ( single carb) to clean & check the float adjustment . just feels more like a ignition related prob, never hurts to know the fuel system is good. I live about a 1/2 hour away from the closest lake to check with a spark tester, may be able to get there Saturday.

 

[pnwboat]

Disconnect the yellow wires that come from the stator to the voltage regulator, tape the bare end off and see if that has any affect.

 

[jerryjerry05]

Sounds like a fuel delivery problem???

​Once the ball pumps up it's job is done and after starting it shouldn't really stay hard.
​It's possible the ball is bad, there is a 1 way valve in the ball, the inline connectors are bad and sucking air?
The fuel line could be bad, soft mushy, the inside delaminating?
​Water in the fuel? Unhook the fuel line at the pump and using the squeezie, pull off some fuel(make sure the nose of the boat is up)
Could be the pickup in the tank is clogged?
​The vent line from the tank could be clogged with wasp nests?

​Clean the carb, a tiny,TINY piece of dirt can cause that.
Make sure the float's set right.
When its off, check the reeds for broken missing parts.

 

[gjess]

i put a kit in the fuel pump . i did find the 2 rubbers deformed, new kit uses plastic , took the carb apart to clean, put a new stator due to the resistance value out of spec . took to the lake today 31 MPH with just me and no gear or front or rear seats. hole shot felt good as well. thanks for all the help. i do have another question . when i had the carb apart i noticed the idle tube sticking out the bottom of the main nozzle , is the right. my Clymer manual says install the tube to the depth and orientate per the picture . it`s not sticking out in the picture. i did not remove the tube out as i did not have a new plug to install. should i tap the tube so it not sticking out the main nozzle . Mack T