Verify wire connections at motor please...

[cct]

Hi all,
I was working on a project and needed to disconnect the wires coming from the motor on the port side midship. I thought I marked them correctly but I lost my tach and other engine instruments so something is screwed up.... The bundle comes from the starter, temp/oil sensors, alt, etc., join at the port side of the motor, then enter electrical conduit as it is attached to the vertical floor support post in front of the port side fuel tank. From there, it runs up to both instrument clusters. Can someone PLEASE describe to me the wire color combo and where each and every one of the wires are attached at the motor? Thanks in advance.

[jleonard]

Which motor?

[cct]

Ah, sorry. FL 120. Some of the gauges weren't working at the helm so that's why I just can't go to there and work backwards. Thanks for the help.

[mike66]

Do you have a seperate voltage regulator? I'll be at the boat later today, I'll take a look and hopefully some photos.

[jleonard]

See attached.

[cct]

Mike: no. Voltage regulator is mounted on back of alternator.
J: Thanks for the wiring diagram. I'll have to look at it closer - I thought I followed it exactly but the Tach is reading ZERO regardless of RPM setting, so I set cruise RPM by sound till I can open it up again.

Ah..., 1 step forward, 2 steps back.

[mike66]

On my boat, the stator output ( the connection to the tach ) is a white wire. I would consult an owner's manual to find out which terminal on your alternator to connect the tach to. Mine is a Balmer, theirs are all available on their website.
http://www.balmar.net/

[jleonard]

Tach terminal is the "R" terminal if labelled. And it is a white wire.
I have an original alternator at home. I'll look tonight and take a pic if I remember.

[mike66]

viewtopic.php?f=63&t=2337

There's an illustration on page 26 that might help.

[rebuckley]

For what it is worth - the original wire on my Tac from the sender on the alt - is yellow with red stripe. I do have a white wire entering the helm (have not traced it back) but it runs to the amp meter gauge.

[mike66]

ABYC code for yellow w/ red is engine starter circuit to solenoid. Here is a copy of their color codes. They list tach circuit wire as gray.
http://www.clrmarine.com/538.html
More head scratching and sleuthing in your future, it seems. Half the stuff in my upper helm panel has clipped wires... luckily the temp and tach work. Another project for another day.

[rebuckley]

I am not sure how ABYC compliant the Taiwanese builders were back in the 80's. I tend to think that with every DC project I take on in this boat.

[mike66]

Whatever wire was lying around no doubt......well, it worked once, it will work again. Good luck with it.

[brookesmith]

One other thing. Our 1979 36 ad a engine harness meltdown. The starting circuit was NOT fused. Looking at Bob Smiths wiring diagram it shows NO fuse either. As far as I can tell the push start button was drawing too much current but was engaging the starter solenoid without fail. At the helm the push start button wires melted together as the return wire was pinched between the starter motor and engine block and the insulation was gone. Anyhow I started the engine and started out on a NIGHT cruise of our creek and we started smelling the insulation melting down as the start circuit had become stuck engaged. I'm sure the starter motor was not running continuous as the pinched area was basically a short circuit with no fuse in the path. The lower helm started smoking. I turned the battery switch off and then things started cooling down. No fire, only lots of stink. The entire wiring harness was melted and all wires needed replacing. I went to West Marine and bought several colors of wire, but they did not have the ABYC yellow/red stripe. I also FUSED this circuit so if this ever happens again the fuse should let go. As far as ABYC and fuses, the only circuit that is not fused is the + battery cable to the starter motor. But ABYC DOES want a battery switch that could be turned off in case of a locked rotor overheat of the starter motor. My boat's starting battery was wired directly to the starter motor when I bought it. Electrically that is the best for conduction. I consider the battery switch as a single point of failure for high starting amperage and two more connections to corrode as well as the switch contacts having some resistance. But, I installed a battery switch per ABYC. Now if I just realize when I have a locked rotor condition on the starter motor I can turn the switch off (that is if the contacts don't weld before i get to the switch.)