1979 80hp merc CDI harness

[artilarygoboom]

So as I keep going through this motor i keep finding more things that need to be done. After doing some research i noticed alot of peoples cdi harnesses are rotted or cracked so i decided to take a closer look at mine and it as well is cracked and some wires have corroded to green. Now I am in the process of doing the carbs couple other things and figured while I am in there i should prolly replace this harness to. My question is how hard is it to do? would i have to pull the power head off? or can i do it while its all together. I am having problems when i go more the 1/2 throttle the motor stalls and dies out and people seem to have this problem with a bad harness i noticed. so i am just trying to eliminate from taking the motor apart again really lol.

[artilarygoboom]

2012-07-27_18-42-51_520.jpg

also looks like someone already replaced 1 of the wires

[myboatisbroke]

to be technical, thats a switchbox, not a cdi, but they perform the same task...I had to do the same thing with mine, I replaced all of the switchbox wires and the other questionable wires while I was in there. replace one wire at a time, so you dont end up crossing one. peel the cover back to where the insulation is not rotted and cut and splice from there. Get rid of that butt connector, its a non-weatherproof type, and you WILL have problems with that connection down the road. If you are good with solder, that is the best, and heat shrink the solder joint. They also make heat shrink butt connectors which work great as well. you dont have to spend a fortune on wire either. most local scrapyards will let you buy scrap wire by the pound... The only thing you may have to pull is the flywheel, and there is a special puller to remove it. If you are lucky the wires aren't rotted much past the cable insulation/conduit.

[artilarygoboom]

well im replacing the flywheel anyways since my timing marks have worn off the flywheel. so ill get a closer look at the wires up top.

[myboatisbroke]

Cool, good luck with it. Cant beat an old merc thats for sure, I am really happy with mine

[artilarygoboom]

does anyone have a label for each of the wires and what there for?

[artilarygoboom]

anyone?

[oldman570]

A manual for your motor will have wireing diagrams and colors of the wires. Manuals are one of the cheapest parts needed to work on a motor and comes in handy down the road. Soldering & heatshrink is the only sure way of getting a good splice of the wires and no trouble later when doing wire repair on outboards as they are in the most detremetal conditios of exposure to electricy. JMO
Oldman570