Johnson 9.9hp (1989) - Idle

I have a Johnson 9.9 on my 14ft Lund WC-14 and been having a problem with maintaining a good idle speed. What is confusing it the Rich/Lean knob and where to set it. I've been looking for the owner's/operator's manual for it with no luck and can't seem to figure out how to use this knob and maintain a good idle that doesn't sputter out. I found that having it in the more lean side allows it to run smooth in gear but not in idle. Can someone please englighten me on this?

low speed needle adjustment, not real sure about a 9.9 but on my 25 you turn the needle/knob clockwise and just barely snug it. if you tighten it too much you will damage it. from there i turn mine out about one full turn and start the motor. after its started i wait for about 30 seconds so the fuel has time to get into the carb and react to the adjustment, then from there i either turn it out or back in about a 1/4 inch at a time while waiting again before any more adjustment. if your motor will start and idle you wont have to turn it all the way in to start, just give it a bit of rich or lean in small amounts and wait and keep adjusting till you like how it idles. do you have a tach? dont need one but if you want to get it to factory specs you will need it.

you could have a leak somewhere too, id check your fuel line,fuel pump and filter and carb and gas line from your tank first before you mess with the needle.....shoulld have told ya that first.... a pro should be on soon and offer more help...

shawnfish said:

you could have a leak somewhere too, id check your fuel line,fuel pump and filter and carb and gas line from your tank first before you mess with the needle.....shoulld have told ya that first.... a pro should be on soon and offer more help...

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Thanks, I'll try to test that out. Do you think I should do it with earmuffs or actually in the water?

Yes, brand new tank and hose so no worries there. I also have some knob at the end of my throttle handle, right behind the kill switch. I don't know what that does either. I thought that may have something to do with slow speed trolling. I don'nt know which way to turn it and it doesn't seem to do anything.

Sarkan said:

I also have some knob at the end of my throttle handle, right behind the kill switch. I don't know what that does either. I thought that may have something to do with slow speed trolling. I don'nt know which way to turn it and it doesn't seem to do anything.

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I'm not sure if your motor is the same as mine, but mine has a knob at the end of the tiller that adjust the friction on the throttle grip rotation. So turning the knob clockwise applies more friction and the throttle will stay where you leave when you let go of the grip rather than returning to idle.

Sarkan said:

shawnfish said:

you could have a leak somewhere too, id check your fuel line,fuel pump and filter and carb and gas line from your tank first before you mess with the needle.....shoulld have told ya that first.... a pro should be on soon and offer more help...

Click to expand...

Thanks, I'll try to test that out. Do you think I should do it with earmuffs or actually in the water?

Yes, brand new tank and hose so no worries there. I also have some knob at the end of my throttle handle, right behind the kill switch. I don't know what that does either. I thought that may have something to do with slow speed trolling. I don'nt know which way to turn it and it doesn't seem to do anything.

Click to expand...

THAT KNOB IS FRICTION CONTROL FOR YOUR THROTTLE, YOU WILL ALWAYS GET THE BEST RESULTS MAKING IDLE ADJUSTMENTS WHILE ON THE WATER, YOU CAN ADJUST IT WITH THE MUFFS AT HOME BUT YOU WILL WANT TO FINE TUNE IT ON THE LAKE. IVE SET IDLES IN A TANK AND TOOK THEM ON THE WATER AND THEY DID NOT IDLE NEARLY AS GOOD AS THEY DID IN A TANK.

SARKAN, IS THIS A MOTOR THAT YOU HAVE HAD OR ONE THAT YOU JUST BOUGHT? IF YOU JUST BOUGHT IT YOU WANNA PUT A NEW IMPELLER (CHECK THE IMPELLER PLATE TOO) AND SEALS IN IT AND BUY A KIT TO REBUILD THE CARB, AND A THERMOSTAT WOULD BE A GOOD IDEA ALSO AND ALL OF IT WOULD BE AROUND 40 BUCKS AND YOU WOULD HAVE PEICE OF MIND.

shawnfish said:

SARKAN, IS THIS A MOTOR THAT YOU HAVE HAD OR ONE THAT YOU JUST BOUGHT? IF YOU JUST BOUGHT IT YOU WANNA PUT A NEW IMPELLER (CHECK THE IMPELLER PLATE TOO) AND SEALS IN IT AND BUY A KIT TO REBUILD THE CARB, AND A THERMOSTAT WOULD BE A GOOD IDEA ALSO AND ALL OF IT WOULD BE AROUND 40 BUCKS AND YOU WOULD HAVE PEICE OF MIND.

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I TAKE THAT BACK, I CHECKED PARTS AND IT WOULD BE AROUND 80 BUCKS FOR WATER PUMP AY,CARB KIT AND THERMOSTAT.

Okay I tried moving the air/fuel mixture around during idleing and it didn't make a difference. When in idle the motor slows down until is goes out. So I end up pull starting and quickly putting it in gear so I can throttle away. The knob on the end of my throttle body and just behind my kill switch doesn't adjust the friction of the handle. I still don't know how it works. Does anybody have an owner's manual for this motor? I included pics

shawnfish said:

shawnfish said:

SARKAN, IS THIS A MOTOR THAT YOU HAVE HAD OR ONE THAT YOU JUST BOUGHT? IF YOU JUST BOUGHT IT YOU WANNA PUT A NEW IMPELLER (CHECK THE IMPELLER PLATE TOO) AND SEALS IN IT AND BUY A KIT TO REBUILD THE CARB, AND A THERMOSTAT WOULD BE A GOOD IDEA ALSO AND ALL OF IT WOULD BE AROUND 40 BUCKS AND YOU WOULD HAVE PEICE OF MIND.

Click to expand...

I TAKE THAT BACK, I CHECKED PARTS AND IT WOULD BE AROUND 80 BUCKS FOR WATER PUMP AY,CARB KIT AND THERMOSTAT.

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It pisses water just fine. that was the first thing i checked when i bought it.

shawnfish said:

Sarkan said:

shawnfish said:

you could have a leak somewhere too, id check your fuel line,fuel pump and filter and carb and gas line from your tank first before you mess with the needle.....shoulld have told ya that first.... a pro should be on soon and offer more help...

Click to expand...

Thanks, I'll try to test that out. Do you think I should do it with earmuffs or actually in the water?

Yes, brand new tank and hose so no worries there. I also have some knob at the end of my throttle handle, right behind the kill switch. I don't know what that does either. I thought that may have something to do with slow speed trolling. I don'nt know which way to turn it and it doesn't seem to do anything.

Click to expand...

THAT KNOB IS FRICTION CONTROL FOR YOUR THROTTLE, YOU WILL ALWAYS GET THE BEST RESULTS MAKING IDLE ADJUSTMENTS WHILE ON THE WATER, YOU CAN ADJUST IT WITH THE MUFFS AT HOME BUT YOU WILL WANT TO FINE TUNE IT ON THE LAKE. IVE SET IDLES IN A TANK AND TOOK THEM ON THE WATER AND THEY DID NOT IDLE NEARLY AS GOOD AS THEY DID IN A TANK.

Click to expand...

That knob is not a friction control knob. It is an idle speed/RPM adjustment knob.
First off...turn that knob clockwise a couple of turns and see if that takes care of your issue. Looks like it is all the way out or slow from the photo. You will have to "blip" the throttle up and back down to see where the RPMs end up. Once you have the RPMs up to where you can set idle mixture then go ahead and set it with the mixture screw. Be aware that you can take the mixture knob out and pop it back in place on the other side of the stop in case it needs to be leaner. It would be a good idea at this point for you to turn the screw clockwise until it is lightly against its seat then open 1.5 turns and start your tuning process from there. In most cases you will need to go in or lean it for best idle.

Can someone help point out to me where the idle screw is at on these things? Also, how many full turns out on that mixture screw? I counted about 3 and 1/2 full turns from the stopping point after turning it clockwise. I seriously need the owners manual for this thing.

Your idle mixture adjustment screw is the middle one on the front of your engine......between the choke and the pull handle.
Your idle speed adjustment is the knob at the end of your tiller (steering) handle. Read my post above yours for how to make your initial setting on the mixture adjustment.