1974, 1150 Merc - Wire Harness Rebuild

[LFR]

Hello all, my project is going well so far. Have carbs & fuel pump rebuilt. Water pump and lower unit complete.
Now I need to replace some cracked wires from the wire harness (most of them)
My plan at the moment is to splice new ends on the wires close to the coupling as possible.
I have the wire & just waiting for the ring connectors to come in. (check out "realdealz & wholesale marine)
I peeled back the e-tape and cant help but wonder, how are the wires fastened to the receptacle to begin with?
If I can, I would prefer to replace the complete strand rather than splice.
Can new wires be soldered onto the back of the receptacle?
How hard is it to get that out of the cowl?
All comments are welcome
Please Advise
Thanks

 

[Texasmark]

Re: 1974, 1150 Merc - Wire Harness Rebuild

Electrical connectors similar to what Merc uses normally either have fixed pins requiring you to solder each wire into the rear of the connector and is a real chore, especially with large multi-pin connectors, or removable pins.

Easy way to tell, is to grasp a pin on the mating side and see if it has any movement. Any movement indicates removable and if you can find out who made the connector, you can obtain a tool which slides down over the pin/socket from the mating side and when fully inserted, it compresses the locking springs allowing you to remove the pin from the rear. That same company can sell you new pins and suitable crimper.

Amp and Amphenol are two large, mature, companies that have a huge international connector business. Good place to start.

On getting it out of the cowl it may be as simple as a clip that slides vertically over the inner side of the connector with the connector being flanged on the outside to lock it in, or it may be threaded whereas a locking nut is backed off to remove, or it may be self locking whereby as you push the connector into the cowl of the engine, the rubber pops out when the connector is fully engaged and removal is just tuck the "ears" in as you work the connector out from the outside.

Got to think about two things here: moisture intrusion into the engine or connector and ability to manufacture a wiring harness as a sub-assembly then mounting the interconnect connector in the cowling with the harness already connected to the block and other associated "engine" parts...don't know when, in the mfg. process the harness is installed. Seems to say that it will have the locking device on the outside and removal will be from the outside and push it in to get it out.

You didn't mention it as an option, but have you looked for either OEM or aftermarket harnesses? They may be pricey whereas pins and a plastic removal/insertion tool are cheap. You may already have a suitable crimper in your tool box or can get one at Radio Shack.

HTH

Mark

 

[LFR]

Re: 1974, 1150 Merc - Wire Harness Rebuild

Thanks Mark, Good Stuff
The receptical was held in from the inside with a split clamp and 2 bolts, came out easily.
The receptical is made up of 2 parts, what i will call the "pin puck" (with pins and wires attached),
and a rubber cover/boot that fits into the cowl. It looks like the rubber boot was filled
with a liquid rubber compound during assembly. Looks completely water tight with no way
to separate the two without hacking and slashing. Looks like butt splices will be it unless the wires
show corrosion from the inside out like a trailer harness.
Pins are firmly in place and do not move however being filled with rubber, may never know how the wires
are attached to the "pin puck"
If you have any tips on separate teh two components, please let me know.
Thanks for the help

 

[Faztbullet]

Re: 1974, 1150 Merc - Wire Harness Rebuild

They are crimped and molded as you have found. It will be cheaper and safer in replace it in the long run. You do not want to loose voltage to switchbox when engine is running as this will usually crap a trigger($300). Look over on the CDI electronics site as they sell them..

 

[Ballymac]

Re: 1974, 1150 Merc - Wire Harness Rebuild

I'd stick with Merc - for the extra bucks, it worth sticking with an OEM product. I know, I know, but had problems with CDI product.