1983 evinrude 9.9 2 stroke idle speed setting

badkarma68

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I have a 1983 evinrude 9.9 2 stroke. I also have a 1980 johnson 9.9 2 stroke. I have searched this forum and I have a service manual and I can not find how to set the idle speed. The only way I found is for the later engines with the cable. I do not have a cable. When the tiller handle is moved to the slowest idle position the cam folower does not touch the plastic cam on either of them. They both idle if I use the tiller handle to set the idle. When it is set this way and idling at around 900 rpm the idle knob, on the side of the case, is no where near the throttle shaft even at it max point.
Is there something I'm missing, like and idle speed adjustment screw on the carb? Both of these engines look the same and neither have a way to adjust idle speed that I can see. The only thing that touches the carb is the cam.
Sorry for the long post.
Thanks in advance
 

oldboat1

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The knob on the right side of the pan will set the idle speed (limits throttle speed for trolling.)
 

badkarma68

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The knob on the right side of the pan will set the idle speed (limits throttle speed for trolling.)
Correct, but when engine is idling(I have to use the twist grip to set idle) the idle adjustment on the side does not contact at its fullest extention.
 

badkarma68

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I guess what I am getting at is how to set the base idle. So when I rotate the twist grip to its lowest setting the engine will idle.it does not do this.
 

oldboat1

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Difficult to follow your narrative. Your first post says the engine(s) idle when the tiller handle is set -- and that the cam follower does not contact the cam at that point. This all sounds normal. Your motors should idle at around 650 rpm warmed up and in gear, on the boat or in a suitable test barrel.
 

badkarma68

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Difficult to follow your narrative. Your first post says the engine(s) idle when the tiller handle is set -- and that the cam follower does not contact the cam at that point. This all sounds normal. Your motors should idle at around 650 rpm warmed up and in gear, on the boat or in a suitable test barrel.
It does not do this. When I twist the grip to as far as it goes to idle the engine dies. If I twist the grip until the cam folower touches the cam it will idle. There is no adjustment that I can see on carb to set the idle. The knob on the side does not have enough reach to achieve this and from what I have been reading this is to set the idle for trolling.
All I am looking for is how to set the idle speed or am I looking for something that can't be done. I would think that when I twist the grip all the way to its furthest point to slow that the engine would idle.
 

badkarma68

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Difficult to follow your narrative. Your first post says the engine(s) idle when the tiller handle is set -- and that the cam follower does not contact the cam at that point. This all sounds normal. Your motors should idle at around 650 rpm warmed up and in gear, on the boat or in a suitable test barrel.
Or maybe a better way to say this. It won't idle unless the cam folower is touching the cam.
 

oldboat1

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Sounds like the idle air/fuel mix is a little lean. Set it 1/8 turn counter clockwise. Repeat as necessary.

When you set the idle mix, rpm will increase as you turn clockwise (leaner). If the engine backfires ("lean sneeze") or stall, turn counterclockwise 1/4 turn. This should be close to the proper setting. As the rpm increase with the lean adjustment, btw, the tiller grip is used to lower the idle speed.

couple of additional points: can't properly make these adjustments running on muffs. If you are unable to get the low idle, chance are that the carb needs disassembly and cleaning, including the idle passages under the aluminum cap at the top. Need a carb kit.
 
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badkarma68

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Thank
Sounds like the idle air/fuel mix is a little lean. Set it 1/8 turn counter clockwise. Repeat as necessary.

When you set the idle mix, rpm will increase as you turn clockwise (leaner). If the engine backfires ("lean sneeze") or stall, turn counterclockwise 1/4 turn. This should be close to the proper setting. As the rpm increase with the lean adjustment, btw, the tiller grip is used to lower the idle speed.

couple of additional points: can't properly make these adjustments running on muffs. If you are unable to get the low idle, chance are that the carb needs disassembly and cleaning, including the idle passages under the aluminum cap at the top. Need a carb kit.
 

badkarma68

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I have read that the idle mixture screw shoud be turned out from lightly seated 1.5 turns and also 3 turns. Can you verify which is a starting point for a 1980?
 

racerone

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Well----1-1/2 is the starting point.------A motor in good condition should start and keep running.-------Then you must do the final adjusting a bit more out or more in. ----So is your motor in good condition ??-----Thermostat installed and motor running at proper temperature ?------Compression test values might be posted here as well.
 

flyingscott

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Make sure the snap ring is on tight and the knob is not pushing out. You may need to modify the adjuster I have never seen one that actually worked correctly. leeroysramblings.com has a lot of good info on those.
 

badkarma68

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Got it!! Idles now. Following oldboat1 guidelines. Everything else is good, compression, spark ect. Just did not know how to make it idle.
Thanks again for all the good info.
I'm sure I'll be asking more questions as I have another johnson 9.9 and a nissan 4 stroke 9.9. Got them all in a trade.
 

Crosbyman

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"The knob on the side does not have enough reach to achieve this and from what I have been reading this is to set the idle for trolling."

did you pull out the threaded push part that goes in the knob and verify that the threads are not stripped. this set-up is a cousin of the early 9.5 side idle knob from the 1960's . the side knob pushes out the plastic part and limits the lower IDLE position of the throttle.handle.

If the threads are stripped inside the knob it will not extend enough to control/limit the linkage limiting the lowest idle setting

Your throttle may also have jumped a tooth or two messing up the markings as to what/where idle should be exactly

read up on Leroy's on tooth jumping...
 

badkarma68

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"The knob on the side does not have enough reach to achieve this and from what I have been reading this is to set the idle for trolling."

did you pull out the threaded push part that goes in the knob and verify that the threads are not stripped. this set-up is a cousin of the early 9.5 side idle knob from the 1960's . the side knob pushes out the plastic part and limits the lower IDLE position of the throttle.handle.

If the threads are stripped inside the knob it will not extend enough to control/limit the linkage limiting the lowest idle setting

Your throttle may also have jumped a tooth or two messing up the markings as to what/where idle should be exactly

read up on Leroy's on tooth jumping...
Brand new knob. It idles now that I correctly set idle mixture. Thanks
 

oldboat1

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Glad to hear you are up and running. If the needle wants to wander when running, you might need to replace the red plastic retainer to tighten things up. Additionally, on my '80s 9.9s, I sometimes need to set the needle a little richer for cold starting (1/8 or 1/4 turn c.clockwise), then return it to the leaner position. Good boating to you!
 
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