merc switchbox question

[reynold460]

hi guys are all mercury switchboxes the same for 3 and 6 cylinder engines ex: if i have switchboxes with numbers 7778a-1 can i use 7778a-12 from what i can find all replacement boxes are 7778a-12

 

[Gomer50]

Re: merc switchbox question

Yes sir that will work the a?? are supersessions.Just updated versions.

 

[CharlieB]

Re: merc switchbox question

I regularly tell V6 owners that replace a switchbox with a bad Bias to mark/paint 'Bad Bias' on the box and hang onto them as they will work fine on a three cyl motor.

 

[Faztbullet]

Re: merc switchbox question

In my book a pack with a bad bias circuit is a bad pack and gets the "hammer" test across the center pack terminals.