1971 Mercury 800 - New Engine/Boat Harness/Switch - No Spark - Stumped

[NDMERC]

Hello,

I recently picked up a 1959 Larson All-American with 1971 Merc 800 and have begun the process of bringing her back to life. The wiring was shot, so I installed a new engine harness, boat harness, battery, and MP4100 key switch. The only thing I didn't touch was the stator wiring. It looked like crap, so I wrapped it as best I could.

1971 Merc 800 SN/3144369 - battery ignition -

Engine Harness - CDI - 4142770
Boat Harness - CDI - 4749550
Switch - Sierra - MP41000

Turns over like a champ, but no spark. I've been through the harness, switch, box connections a hundred times and am stumped. No spark from the coil.

My questions:

-At the switchbox, I have 12v on the white wire(ignition) in RUN and START. What should the RED have? 12v as well? I'm not getting 12v.

-I've jumpered the red from the rectifier to the box as shown in the wiring diagram.

Am I missing something at the key switch? The new switch is a 6 terminal and the original was 5. The 6th terminal was for a magneto circuit, but I left it alone(no connection).

Any other ideas?

Thanks,

Nick

 

[NDMERC]

I just wanted to let everyone know I figured this out! The red lead on the switchbox needs 12v to produce spark. I jumpered the white to the red to supply 12v and boom, fired right up.

 

[Watermann]

Good to hear you got it going but just know it's not a good idea to not replace the stator if the wiring on it is bad, sooner or later best case you'll be getting towed in or it could catch on fire worst case. As I'm sure you've seen the old wire itself on these motors gets that nasty hazy corroded look to it which causes resistance.