[Ken Corkey]

Anybody?! What are the settings for the needle valves on a 2000 40hp Yamaha? How many turns from the closed position?

[bgbass.1]

if i remember right go 2 turns and then adjust from there

[rodbolt]

depends on year model and number of cylinders and 2 or four stroke.
seems yamaha actually made more than one 40 horsepower model. imagine that.

[rodbolt]

my bad
00-05 carbed 4 strokes have EPA carbs . that means your supposed to count the turns in and record it.
however if you will start about 1 3/4 it will get you close.
if its a 2 stroke model set the pilot screws at 1 1/2 from seated.

[Ken Corkey]

Thanks

[capf]

2002 yamaha 4 stroke, 3 cyl, 3 carbs, cleaned carbs engine starts and runs well at idle, will not go over 2000 rpm, stalls at about 2000. everything looks ok inside carbs, plugs are new. Looking for suggestions. Tried boring out low speed jets little bit and that seemed to help starting and low speed, then tried boring out main jets and that was a mistake. waiting for new, stock jets. Fuel has some ethanol mix, owner has added something supposed to compensate for the ethanol.

[cprince07]

i have a 2000 Yamaha 40 hp (f40esry) with the same problem. It sat for 1 year. i replaced the fuel tank, both fuel filters,removed the carbs and cleaned them and replaced the plugs. It idles fine but when i i give it the gas to go on and take off it dies, when it does die it will started right back up and idle perfect. It acts like to me it is starving for fuel under a load,fuel pump maybe?? Any help would please?