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1975 9.9 evinrude idle adjustment

D

dtoole

Regular Contributor
im working on a 75 9.9 envinrude. it has idle mixture knob on inboard side of motor. where should i set the idle mixture screw before putting knob on ? also...does this motor have a pee port or does all cooling water exit through the exhaust.
 
Also, this is just the starting position. Once it is running you need to fine tune it. To do so, warm up the motor and then bring it to a very slow idle. Turn the knob clockwise 1/8 of a turn and wait 5 seconds for the motor to respond. If the idle increases, slow it down again. Do another 1/8 of a turn, etc. Keep doing this until the motor sneezes and wants to stall or does stall. Turn the knob back 1/4 turn counter-clockwise and leave it there. As will says, take the knob off and reposition it so that the pointer points straight down so you can adjust it in either direction and more importantly you know if someone else adjusted it.
 
optsyeagle, I'm interested in your comment about changing the position of the mixture knob. I have a 66 9.5 Seahorse that currently has the mixture know set at the 8-oclock position in idle. I have not had the motor on the lake yet (this weekend!) but I was wondering how I can adjust the mixture knob assembly, once set, to be in the 12-oclock position.

OP - don't mean to hijack your thread but my question seems related.

Thanks,
CMOS



optsyeagle said:
Also, this is just the starting position. Once it is running you need to fine tune it. To do so, warm up the motor and then bring it to a very slow idle. Turn the knob clockwise 1/8 of a turn and wait 5 seconds for the motor to respond. If the idle increases, slow it down again. Do another 1/8 of a turn, etc. Keep doing this until the motor sneezes and wants to stall or does stall. Turn the knob back 1/4 turn counter-clockwise and leave it there. As will says, take the knob off and reposition it so that the pointer points straight down so you can adjust it in either direction and more importantly you know if someone else adjusted it.
Click to expand...
 
You remove the knob from the mixture screw.------Then set the idle.------Then put the knob on so you can go both lean or rich a little.-------That knob was put there so an owner can adjust for fuel quality and local atmosheric conditions without using tools !
 
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