1994 Force 120 dies when put into gear.

[Kelly62]

I put it in water this weekend and it dies when put into gear. I am assuming it is becauce of the back pressure. Gas tank has been drained and has new gas,new fuel water seperator. compression is 145 psi all 4 cylenders. idles good on muffs with a hose. I don't have a functioning tach so i don't know the persice rpm's. I could slam it into gear and it will run really well. I know I am supposed to forcefully shift into gear as opposed to easing it into gear but i think it should continue to idle/run in gear. Should I loosen up the lock nut and increase the the idling with the screw a little bit? Any help would be apericated.

 

[SkiDad]

since you don't have a tach I would do as you said - i would make 1/16" adjustments at a time in the water. it doesn't take too much to get the rpm up. Turning to right will increase idle. Make sure you tighten the lock nut before you go faster than idle speed - don't ask me how i know it 's a long story.

 

[flyingscott]

Before you adjust anything you might want to determine if your motor is running on all 4 cylinders. Did you do a spark test.

 

[tommarvin]

1. We have a 125hp, and its 750 rpm when just put in gear, 1000rpm out of gear.
2. Could be dirty idle jet(s) Clean/rebuild if RPM is to low.
3. You could increase the idle, but if it's to high it trashes the gears, every time you put it in gear.

 

[foodfisher]

RPMs are needed for many fixes. Tiny tach is an inexpensive solution.

 

[Jiggz]

If it idles fine on muffs try placing it in gear while on muffs (just make sure you stand clear of the prop and do not rev). Does it stay on? If not then try adjusting the screw 1/8 of a turn. Does it stay on? If not, you are most likely not firing on all cylinders.

If it stays on when placed in gear while on muffs, you probably just need to raise the idle speed a bit. However, if it still dies when placed in water, try running it without the upper cowl to see if it is exhaust leak that is making it hard to stay on in gear. If you see smoke exiting from the upper cowl you most likely have exhaust leak. If it stays running in gear without the upper cowl you most likely have an exhaust leak.

 

[jerryjerry05]

Dirty idle jets?? He said it idles good.
Dirty jets and it wouldn't idle.
Foodfisher said it: A Tiny Tach or equilevent .
Get that or a timing light that can read rpm's and set yours at 750-800 in gear in the water and 1100 in the driveway.
The air screws control the low speed idle. Start at 1 and 1/2 turn out.

 

[tommarvin]

Don't the air screws control the air/fuel mixture only, and the idle screw controls the idle speed only, and the air fuel mixture screw controls the mixture for the high speed jet.

 

[jerryjerry05]

Tom, NO.
​Air screw: controls the air/fuel at idle.Should be set in the water and in gear motor warm.
The idle screw: controls the rpm's at idle and if set up right?(link and sinc) the position of the throttle link.
High speed jet: no control or adjustment unless you change the jets.
The only thing that would affect the HS is a float out of adjustment. You'd run out of fuel too quick.

Any body that says "this has to be your problem" without physically working on an engine is giving the wrong advice.
WE give suggestion and possible remedy's to a problem.
I know some?? Some know more? Frank was great on the older Chryslers electrics, I'm not.