78 Mercury 50hp wiring harness DISINTEGRATED!

[LibraLabSoldier]

The title pretty much says it all. I am not a boat guy, I am a car guy. I got this boat in a trade, and it is constantly giving me issues. I was trying to sort out why it would turn over but not start, began tracing the wiring and the wiring harness was so corroded and old that it just crumbled in my hand.

Talked to a guy at one of the local boat repair places and he says that they may be able to find a replacement, but it looks like I will have to completely redo the wiring in this motor.

 

[tim1986]

Re: 78 Mercury 50hp wiring harness DISINTEGRATED!

Hey i just ran into the same problem as you did the other day. i just ended up rebuilding the wiring harness with new wire and what not. but i would say check out maxrules.com they are based out of florida and seem to have the harness for about 160+. im assuming it is the internal harness. what is the serial # and how many cyl does it have??? electric start or manual??

 

[LibraLabSoldier]

Re: 78 Mercury 50hp wiring harness DISINTEGRATED!

I found this, for 140 shipped. http://www.**********/parts/search/Merc/Mercury/1978/1050208/ELECTRIC COMPONENTS/parts.html

 

[chum1]

Re: 78 Mercury 50hp wiring harness DISINTEGRATED!

if thats a floats.net with a b address it will be a dead link?

 

[LibraLabSoldier]

Re: 78 Mercury 50hp wiring harness DISINTEGRATED!

I am looking at it, unless there is some beef between the two sites?

 

[cmayhle]

Re: 78 Mercury 50hp wiring harness DISINTEGRATED!

...began tracing the wiring and the wiring harness was so corroded and old that it just crumbled in my hand.

I am seeing the same thing with my 1976 500, 50. iBoats.com sells CDI aftermarket internal engine harnesses for your (And my) engine:

Mercury Marine 414-3369 Internal Engine Harnesses - CDI Electronics

Look this up on iBoats, it is $150.

It replaces the original part Mercury 84-73447, which is also available for a similar price from outlets with OEM parts

 

[1nebel0]

Re: 78 Mercury 50hp wiring harness DISINTEGRATED!

All of the older Merc's will do this unlike Johnson's...I still like Mercury! Look on Ebay as people are always parting out motor's and these can be had cheap if you are willing to wait for one to come up..CDI makes a good one and any marine shop can order...

 

[LibraLabSoldier]

Re: 78 Mercury 50hp wiring harness DISINTEGRATED!

I still have the boat listed for sale on CL, but if I do not get it sold I will get the harness and fix it myself when I get back from my vacation. If anyone wants it, it is going cheap, considering the shape it is in and all.

 

[TGC357]

Re: 78 Mercury 50hp wiring harness DISINTEGRATED!

Sounds like you are referring to just the Internal Engine Wiring Harness.

Sadly, the External Wiring Harness (Sierra 18-5511 / Merc 84-822253A20) usually turns to crap at about the same time and you'll find that all the wires in the control box look like what you've described.

Good Luck, Tom