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problem with 75 hp mercury and not sure of age

99_sierra

New member
hey was just trying to find ou

hey was just trying to find out what year my 75 hp mercury was i'm having some issue's with 3 and 4 spark not firing i chased a wire coming from under the flywheel and it was hard like it was heated up and green crosion from the wire so i replaced the bad wire and i can't get any spark on 3 and 4 cylinder i think all my coils are good .........here's the number off the motor 7208790
 
"Jim, posted the year in your

"Jim, posted the year in your other thread - it's a 1980/81 model built by Merc in Canada.

No spark on 3 and 4 is most probably a bad stator or bad switchbox.

Since you already have evidence that the stator has/had an issue, that would be my first suspect."
 
ok it had the bad wire on the

ok it had the bad wire on the trigger will that cause it to drop fire on 3 and 4...the wire's were fine on the stator
 
"Trying to think back to earli

"Trying to think back to earlier 4 cylinder models - not my specialty.

If I have my charts correct you should have 4 trigger leads - purple(violet), white, brown and black feeding the switch box.

Quick test - swap the purple with the brown and the white with the black and see if the problem moves to cylinder 1 and 2 - if it does, replace the trigger."
 
hey graham i changed those 2 w

hey graham i changed those 2 wire's around like u said to try and i still only have spark on 1 and 2 only i thought they spark would've moved to 3 and 4 but it didn't still only have spark on 1 and 2 so i'm gussing the switch box is junk...it was brand new but with that bad wire from the trigger must of shorted out the switch box what do u think....
 
"Yes, since the problem didn&#

"Yes, since the problem didn't move really sounds like the switch box..."
 
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