1989 Mercury V200 Power Packs
 

I have been having problems with the power packs (switch boxes) and although I’ve heard that you should replace both if one goes, I have only replaced the one that goes bad (they are about $170 ea.). But it’s happened over three times in less than a year. Is there any truth reasoning that they both need to be replaced if only one goes? Should I be looking at other ignition components that may be causing the early failure of the power packs? As always, your help is appreciated.
:beer:

the bias circut connects the two switch boxes, irregularvoltage can cuase the good one to damage the bad one. Allways replace them in pairs. I allways check the stator while I'm at it

i'd replace the motor, at $170 each any 3 in a yr at $510 you are close to a good used Johnson/Evinrude

Hey builder see if this helps. http://www.outboardignition.com/ I wonder if ometing is causing the one to go bad like a bad coil on that side. This website had a pretty easy way to troubleshoot. Hope it helps.

Spare is probably right, but I've also seen a bad coil cause the switchboxes to go bad.

I have a box of 50+ used v6 switchboxes. $25/each and I'll send you as many as you like. Which cylinder (s) are you losing spark on? Follow it back and replace the coil also check the wires from the coil to the switch box.

BS, check you PM's.

PD - Just responded.