1979 merc 70 switchbox

[dcmtfam]

Bought a project boat with a 1979 70 hp merc (cdi ignition with 3 coils). there was no spark when I tried to fire it up. I found a short in my wiring harness and 12v power went to the kill wire to my switch box when I push the choke. I have fixed this short and still have no spark. Would thi fry the switch box? Would it damage he stator or trigger. How would I tell?

 

[j_martin]

Re: 1979 merc 70 switchbox

Bought a project boat with a 1979 70 hp merc (cdi ignition with 3 coils). there was no spark when I tried to fire it up. I found a short in my wiring harness and 12v power went to the kill wire to my switch box when I push the choke. I have fixed this short and still have no spark. Would thi fry the switch box? Would it damage he stator or trigger. How would I tell?

Try disconnecting the kill wire(s) from the switchbox and see if it has spark. Still no spark measure the voltage from the stator with a DVA. That will determine if it's switchbox or stator. Likely the switchbox is fried, but both parts are expensive enough to make it worthwhile to acquire a DVA to determine which one it is. Besides, then you have the DVA which you will probably need in the future on this one.

hope it helps
John

 

[dcmtfam]

Re: 1979 merc 70 switchbox

Tried it already with the kill wire removed there was no spark. What is a DVA? I have a good digital multimeter. How much should a DVA cost?