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Requesting an experienced second opinion on 1976 9.8 before ordering parts

FXS

New member
1976 Merc 9.8 110 Canadian
Serial No. 7074559

I decided to go fishing for a few hours and found that I only could get 1/2 throttle and believed I was only running on 1 cylinder.
Sure enough no spark to bottom piston.
I checked out both coils with meter and they checked out. Wires and plugs checked. I moved to the switch box and found the wires for the bottom piston dried out and cracked and crumbly. I did my best to solder in 2 new copper wires close to the box and ran the new wire up to the coil.
Still no spark on bottom. Only top...
This motor has been in the family since new so I have no problem spending s few bucks to keep it going for another 10 years or so.
I believe a new CDI Box will do the trick.
Am I on the right track? Thanks to all in advance...
 
Switch the coils and see if the spark moves to the bottom plug, if so the lower coil is no good - if the spark stays on the top the trigger could be expired. Check the coils and cowlings for good ground wires.
 
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Thank You All....
I swapped the coils, right to left and still to spark on the bottom. Looking from behind the motor the left coil worked on the right side..Spark...With the right coil on the left still no spark on the bottom..
Thanks again...
 
I become think that, could it be possible that spark plug is just dead, even if it looks usable?
What kind of spark plugs you have, conventional or Mercury special type surface gap plugs?
 
Sorry for the confusion. I have the no gap flat spark plugs and both are new and working. I thought the left coil might be bad so I moved it to the right, connected the wires from for the top piston and and got good spark. When I return the coil back to the left and connect the its proper wires from the bottom piston, no spark. So I am left with good coils, wires and plugs. As I mentioned before the wires from the switch box are in very poor condition so I suspect a new one will be my move..
Thanks again to everyone who helped me out...
 
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