Pay attention to the color codes

[Texasmark]

Don't know where this goes here or in OB discussions but this is a Merc Repair point:

Was in my service manual yesterday and looking at my engine and stumbled across something easy to overlook (I did......but I don't repair engines for a living and don't look in there that often).

In the wiring diagram they use color coding like "blk/yel" and also use "yel/blk".

When you are fiddling around in the engine and looking at wires, pay attention to which color is listed first in the wiring diagram. First is the wire basic color and the second is a stripe on it. Very easy to be looking for black and yellow colors and wind up on the wrong wire.

Like yel/blk is one wire and goes to the fuel enrichment valve.
Blk/yellow is 6 wires and go to the ignition modules.

HTH someone.
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So, Willy or Silver or other mech, what does the black/yellow wire from the ignition switch to each module do? I assume it kills the module when you turn the key off, but what does it do inside the module?
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Thanks,

Mark

 

[DHPMARINE]

Re: Pay attention to the color codes

good point on the coloring.It's easy to get confused unless you do work on them alot.

black/yellow grounds the module to stop the spark.

DHP

 

[Texasmark]

Re: Pay attention to the color codes

Confession time.

I didn't think my fuel enrichment valve was working and being hard of hearing I thought I'd get back at the engine and exercise it. I got mesmerized with the little button on the top for manual operation; thought that was supposed to suck down when you hit the choke button. Didn't realize that it was not connected to the solenoid and was spring loaded in the up position. Know now.

What chapps me about the whole thing is that I knew darn well that the enrichment valve was working when I started the engine the last time......eat up with the dumb-ass, tunnel vision, all of the above. d

So, I got a 4' piece of wire and plugged it into the test socket for the ignition kill wire by mistake (for the reason mentioned) and held the other end of the wire on the battery + terminal.

I had it on there for a couple of seconds and the wire (that I was holding) got real hot. Immediately removed it. Obviously the enrichment valve did nothing as I was in the ignition circuit.

So, I got out the manual and the only thing it said to do to check out that circuit (ignition kill) was to probe that test connection with the ignition on and insure that no ground was present. I did and it was open ckt in the RUN position as stated. Had about 22 ohms in the Ignition Off position.

I started the engine several times and stopped it and it immediately responded to the KILL.

Just wondering if I messed something up.

Thanks for your reply,

Mark