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Johnson 99 running one cylinder only

C

clint

New member
"I have a 1976 Johnson 9.9 rop

"I have a 1976 Johnson 9.9 rope start outboard, model # 10R76R. It is currently running on only one cylinder. It has new coils, and when I switch the lead to the opposite coil, that cylinder runs fine. There is something not sending power to both coils simultaneously. Is this a bad power pack? Does this model even have a power pack? All the information I have found about this model insists that from 1974 to 1976 all Johnson 9.9 motors had a straight magneto setup with points and condensers. On the other hand, there is a Mag Flash CD decal on the front of the cowling that indicates the motor has an electronic capacitor discharge ignition.

Any help you could offer me would be appreciated."
 
"Wrong hood maybe ????, newer

"Wrong hood maybe ????, newer power head installed maybe ??? Have you checked for a broken reed valve???Have you checked the actual strenth of the spark 7/16" gap?"
 
"the model number u have poste

"the model number u have posted....has brkr points,condensors.Look on side of block,..do u see a 4 inch black or blue plastic module or 'box'...that ,would be a pwr pack."
 
"No, I don't see a power p

"No, I don't see a power pack. It must of had it's cowling replaced at one time. A friend just gave me this old motor. He said he recently had it tuned up, both coils replaced, and new points and a new condenser installed. After all this, he ran it for about 3 trips before it started acting up.

Both coils and cylinders fire, just not at the same time. If there is no power pack on this model, could it be the magneto?

Thanks"
 
when you say you "switch t

when you say you "switch the lead" what do you mean? you can see this model on evinrudes website--
 
"what do u mean..not at same t

"what do u mean..not at same time?....i may be mis-understanding your statement,..but,they are not supposed to fire at the same time."
 
"The # 2 cylinder is not firin

"The # 2 cylinder is not firing when hooked up correctly.

When I plug the lead going from the magneto to the # 1 coil into the # 2 coil, it fires. When I plug the lead going from the magneto to the number 2 coil into the # 1 coil, it does not fire."
 
Pull the flywheel and check op

Pull the flywheel and check operation of points.Maybe something ( a screw ) came loose and allowed point gap to change.
 
"prob dirty/bad/mis-gapped poi

"prob dirty/bad/mis-gapped points.they need to be VERY clean...use alcohol if avail...gap at .020..i would suggest,a full tune up w/new ones,if u are going in there anyway...fix her up!!"
 
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