graphicideas1

I have a 440, it was not getting gas. I took apart fuel pump cleaned & reassembled. Now I see it is getting fuel. It will only start if I put my hand over the carb. And will die if i do not "feather" my hand over the carb.

Moonracer324

What happened with your primer? I had the same problem with my 550 and needed to adjust the mixture screws more open to allow more fuel. If it starts and dies out fuel sounds like main problem.
Recommended screw adjustments for a JS440:
YEAR.......low speed(turns-out).......highspeed (turns out)
1977-1979........5/8...........3/4
1980................5/8............1
1981-1989..........1............5/8
1990-on............7/8...........3/4
These are only starting points for the mixture screws and the proper adjustment could be more or less from what the starting point is.
Good luck

graphicideas1

Which screw is which?

Moonracer324

The low speed mixtue screw is located on the same side as where the throttle connects to. The high speed is on the opposite side of the carb.

jonesy54

if you get to looking real hard, some carbs will have a "H" or "L" stamped/embossed on them near the screws. but some dont...

__________________
-1990 X-2 - the weird one
-1987 JS550 - bone stock and staying that way for now
-1984 JS550 - restored, 440 pump, Skat Trak, primer, thumb throttle

graphicideas1

My carb has 3 screws - what is the extra setting? Where should that be? I have a aftermarket intake & pipe,

jonesy54

I hope this is what your carb looks like.



#17 is the Low Speed Mixture Screw
#21 is the Pilot (Idle) Mixture Screw
#24 is the High Speed Mixture Screw
#14 is the Throttle Stop (Idle Speed) Screw

Carb tuning. JS440. - PWCToday

__________________
-1990 X-2 - the weird one
-1987 JS550 - bone stock and staying that way for now
-1984 JS550 - restored, 440 pump, Skat Trak, primer, thumb throttle

graphicideas1

That is it. My motor is a 550 not a 440. Does anyone know where i should start my settings at with aftermarket pipe & intake? Also I read a little about needing a fuel restrictor since my rev limiter has been removed. Do i need to add this? I have a drilled out aluminum bar ready to install if needed.

jonesy54

i dont know about the rev limiter issue but i'd start with the stock 550 needle settings and tweak from there.

here are the stock settings

__________________
-1990 X-2 - the weird one
-1987 JS550 - bone stock and staying that way for now
-1984 JS550 - restored, 440 pump, Skat Trak, primer, thumb throttle

jonesy54

I leave mine on the trailer but in the water on the boat ramp to fiddle with the mixture settings. that way i can work the throttle and play with he mixture but not go anywhere or have to balance.

__________________
-1990 X-2 - the weird one
-1987 JS550 - bone stock and staying that way for now
-1984 JS550 - restored, 440 pump, Skat Trak, primer, thumb throttle