45 hp merc classic 50

Hey guys, i'm about to throw in the towel i think. I have a 45 horse mercury from the 80's. I've done nothing but work to this thing. I normally fish 5 days a week, but I have only been out 5 times in the past 4 months now because of this motor.

I have no spark on cylinder 2. This is a 4 cylinder engine with 2 carbs. I've replaced the plugs, coils, and swapped plug wires and that's not it. still no spark.

I've heard it cannot be the trigger or stator because I would lose fire to more than one cylinder.

Is it the switchbox? Are there any more parts it could be? My mechanic wants 200 bucks for a diagnosis, and I can't see dumping that much money plus parts and labor into a motor that is 30ish years old.

coreyprashaw said:

I've heard it cannot be the trigger or stator because I would lose fire to more than one cylinder.

Is it the switchbox? Are there any more parts it could be? My mechanic wants 200 bucks for a diagnosis, and I can't see dumping that much money plus parts and labor into a motor that is 30ish years old.

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You said you only have fire on 2 cylinders, doesn't that satisfy the part about losing fire on more than one cylinder? What do you estimate the value of the motor to be if it was running right and how much would it cost to replace the switchbox new or used?

I said that cylinder 2 is not firing, like the second cylinder from the top. Not 2 cylinders.

coreyprashaw said:

I said that cylinder 2 is not firing, like the second cylinder from the top. Not 2 cylinders.

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My bad, maybe I'm dyslexic. LoL How about the value?

I think it'd be worth the fix if I knew the problem and could just tell the mechanic to replace that part. Rather than him using up his time figuring it out and charging me out the butt

See link, a Merc 35hp, had no spark on the bottom cylinder 0 switch box replacement fixed it:

https://www.marineengine.com/boat-f...2512-No-spark-bottom-cylinder-an-35hp-Mercury