TOPIC: External wireing harness for 1968 50 HP Merc

My neighbor is having problems finding a external wire harness for his 68 50 hp Merc 500. He does not have internet. His mechanic claims the part is not available and I am wondering why? I am waiting for my neighbor to give me the motor serial number.

Is there somewhere I might find this part in reasonable condition?
Why is finding the part (68) more difficult than other year models?

Thanks

I'm pretty confident that most any external harness with a 'cobra-head' type plug-in that goes to the round receiver on the starboard side of the lower pan & has (7) female receivers (holes) from about '67 thru '79ish off any 4 or 6 cylinder Merc will work.
The complication related is that through those years various different combinations of the pins were used & some of the ignition switches throughout those years either interrupted a 12vdc(+) to kill the engine, or completed a connection to engine ground (-) to kill the engine.
So-o-o,...Having said all that, you guys will need to find the appropriate ignition switch and a decent external harness to work with.
THEN,...Since Mercury used a variety of color codes in different years of this specific era, you will need to identify which color code you find the wires to be, and connect them correctly to the ignition switch.
Unless there is something catostrophically wrong with your existing harness & ignition switch, you can always cut off the ignition switch end of the harness a foot or so to find good wire, and then solder these directly to the ignition switch - paying attention to how long of a lead you need to leave in each case so everything will tuck back into the control box safely.
Then,..I cut off the large red (+) battery lead about 3" out from the cobra-head, clean the wire the best you can, and then solder on a new length of 6 GA red battery cable using a butt connector at this splice & then solder on a 6 GA to 5/16" or 3/8" brass eye at the battery end. Shrink wrap all the connection with (2) layers of shrink wrap.
Do this same process to the large black (-) battery cable, but stagger the slice position at the cobra-head endso there is less likelyhood of the two butt connectors every rubbing through and contacting each other.
HTH,
Doc F.

Ebay 280 842 038 847. new about $200.00 made by CDI

I have used their products and very hap pie with them both internal and external used both on my 650 had broke sockets in the cobra plug on two

Charles

Another possible source is Ferguson-Poole. Joe Poole has a number of external harnesses for old Mercs. I spoke with him a while back and he had one to fit my 1964 650. I don't recall if it was NOS, used, or aftermarket. Joe has helped me with some hard to locate parts for my 650. Click on his ad in the upper right of this screen.

My harness was all corroded an I just re wired it now the engine runs fine. Do it just like Dr. Frankenmerc says and it will save you $$.