force 150 wont go above 3000 rpm feels like a 50 horse

[maverick360d]

Hi i have a 20 ft bayliner with a 1990 force 150 outboard i took it out had a little prob starting but it ran and we went out , but even at full throttle it did maybe 20 mph and barely got on plane the prop is a little tore up but not as bad as to make it run like this i had a vent problem on the tank but i have fixed it and cleaned 2 of the 3 carbs so far a little excess oil in them but not bad and i mixed my gas 40 to 1 but im not thinking cleaning the other carb will fix my proplem any ideas guys thanks for all your help

 

[pnwboat]

Re: force 150 wont go above 3000 rpm feels like a 50 horse

Do compression check and verify that you have spark on all 5 cylinders.

 

[bentle]

Re: force 150 wont go above 3000 rpm feels like a 50 horse

Mix should be 50:1 with an 87 octane. What size prop are you running? You may need to sink all carbs. Also try running with the cowl cover off at wot and see if that makes any difference, an exhaust leak will choke out the motor. Let us know what you find.

 

[maverick360d]

Re: force 150 wont go above 3000 rpm feels like a 50 horse

yeah thanks i saw that i should check spark and compression on a differant thread compression was 175 all the way around its supposedly a fresh top end just sat for 2 years ill verify the spark and maybe get new plugs any other ideas let me know thanks guys

 

[maverick360d]

Re: force 150 wont go above 3000 rpm feels like a 50 horse

13 3/4 i think with a 15 cup thats all i could find out on it , sinking the carbs was my next idea as well i have a motorcycle carb sinker can i use that to sink the vacuum ? and i did run the motor with the cover off no differance only that my father worked the throttle from back there and i wasnt getting wot from the controls but very very close when he did open it all the way it would try to bog down then just continue to run at the same rpm or at least sounded like it no differance in speed . thanks for all the ideas guys keep them coming, oh and i did mix it at 50:1 ratio my dad reminded me thanks agian guys

 

[maverick360d]

Re: force 150 wont go above 3000 rpm feels like a 50 horse

hey guys i cleaned the carbs and whoooooooo what a differance i had my doubts but the bottom carb was totally gummed up and that fixed it but what do i set the idle screws at they were set a 1.5 turns out and i have them set at 2.5 now but still at a high idle do i need to sync the carbs or turn the idle screws out more thanks guys preciate all the help

 

[pnwboat]

Re: force 150 wont go above 3000 rpm feels like a 50 horse

Typically the idle "air/fuel mixture" screws on the carbs themselves should be 1 to 1 1/2 turns out from lightly seated. Idle "speed" is set by adjusting the screw on the towershaft (see red arrow). It has a lock nut to prevent it from loosening up.

 

[jerryjerry05]

Re: force 150 wont go above 3000 rpm feels like a 50 horse

Air screws start at 1 turn out.Idle at 750-800 in gear and motor warm.
After the motor warms.Turn in each air screw till it makes the motor buck/kick/stutter or stall.Then back out 1/2 turn,.
First post in the Force foum is a link by FrankA Called a link and sinc.Do that.Then reset the air and idle again.J

 

[maverick360d]

Re: force 150 wont go above 3000 rpm feels like a 50 horse

okay i see now and thanks for all your help guys last question so if thats the idle screw what does the linkage between the 3 carbs do ? the center carb is static and cant move and the top and botom have an adjustment screw ? is that to sync the carbs? thanks for all your time awesome forums

 

[maverick360d]

Re: force 150 wont go above 3000 rpm feels like a 50 horse

Does anyone know what a exhaust standtube is and if its important ? inside the leg there is a small round tube with a clip and i seem to have found it floating around in the exhaust part of the leg ? any ideas thanks

 

[pnwboat]

Re: force 150 wont go above 3000 rpm feels like a 50 horse

That happens on occasion. There are two holes in the lower leg cavity where the exhaust and water exit the motor. The tubes are supposed to be inserted into those two holes so the water level in the cavity rises to a certain point before it drains out. I think it's to cool the lower leg housing, not sure though. To put them back into place, you have to remove the power head. Seen many motors run without them. Doesn't seem to hurt anything.