Wiring on 1973 Merc 850

[egclassic]

A boat I just purchased has a '73 Merc 850 with Thunderbolt ign. and it looks as though I am going to have to do some re-wiring on it. Most of the wiring has cracked insulation and it seems very brittle. I thought I read somewhere that older motors may have used aluminum wiring, anyone know if this particular motor has it? I have not brought the boat home yet to check it myself.

 

[emckelvy]

Re: Wiring on 1973 Merc 850

No motors I know of use aluminum wiring. All of them have stranded, marine-grade copper wires.

If the harness isn't completely deteriorated you can cut back to good wire and splice in a new hunk of wiring.

Use uninsulated crimp-type splice connectors and solder afterwards for a better electrical connection. Insulate the joint with a one-layer wrap of electrical tape and use a length of shrink tubing overlapping the splice for a clean, sealed joint. She should be good as new.

If the wiring harness is completely gone, you can get new ones though not inexpensive. Also check on eBay as clean useable harnesses do come up from time to time.

Another good resource for used parts is your local Craigslist free classifieds.

www.craigslist.org

You may find a complete parts motor for less than the cost of a new harness.

HTH & G'luck with the repairs...............ed

p.s. if you need to look up Merc parts, try this site:

http://www.mercruiserparts.com/SelectModelType3.asp?class_id=2