A4 Electrical Wiring Schematic

[SimonP]

tip for wire ID/color coding

castinemarine was looking for some wire - yellow with red. A more permanent DIY approach than vinyl tape is to get some heat-shrink (polyolefin) tubing, commonly used in hobby electronics. This stuff is great for insulating solder joins etc, and comes in a range of colors and sizes. often, I use a short length (1/4") at each end of a custom wire to color code it. You can use a heatgun to shrink it, but I usually just wipe to with the shank of my soldering iron. It closes up so tight I'd guess it's as good as airtight.

[Mo]

Don,

Great Post #2 wiring schematic. I have a complete identical gauge cluster from a newer boat than mine. My friend re-powered his '"79 C&C 34 with diesel and I bought the engine and instrument cluster about 2 years ago.

The wires attached to the gauges are all long, coiled, and a brief glance tells me they are the same as on my "76 C&C 30. I was figuring I'd replace the weathered cluster on my boat this spring.

Your diagram will make that job a walk in the park.

[HOTFLASH]

I found #12 yellow/red stripe wire by foot

I have been looking for the wire to rewire the Ignition switch to the starter solenoid. Does anyone out there know where I can procure about 18' of this discontinued product? It's 12 AWG Tinned Copper primary wire, Yellow with a Red Stripe. Someone must have a bit of it around. Thank you all for looking or putting me in touch with a source!

http://www.reddenmarine.com/boat-parts/electrical/wire/primary-wire/12-primary-wire-yellow-and-red-foot.html

Mary

[macgyro]

Fuses in the diagram

Hey guys!
Quick Question. I'm having trouble finding the right fuse (40A) to run between the alternator and battery/ammeter. I've eliminated my ammeter because it was quite corroded, and run a short #8 wire from the alternator output to the BATT (large) terminal on the starter solenoid and then straight to the battery through the wire that was already there. (Bypassing the tiny BATT terminal on the ignition switch.) The only fuses I could find were the large plate style and I couldn't find an inline version.

Is this something where I will have to mount a fuse box on the side of the engine compartment, and install the fuse, or does someone make an inline 40 amp fuse holder? Also, do I want to put a 40 amp fuse on a 55 amp alternator? I may even have the larger alternator, I don't really know.

Thanks,
Dean

[joe_db]

Better version IMHO:

[joe_db]

V2 with shunt to measure battery current

[MLW]

For some reason, this past year has seen a large number of our customers facing exactly your same problem. We have developed a kit over the past several months containing all the correct ABYC-sized and color-coded wires, terminals ends and detailed guidance for replacing the DC power distribution on an Atomic 4.

I've looked at this diagram and I'm having a hard time with the 20 amp fuse on feed to ignition switch (red) and the 20 amp fuse on the wire to coil positive (purple). Is the fuse on the ignition wire redundant? Thoughts?

[ndutton]

I think I can help. The drawing posted in the thread appears to be a modification from an earlier version that had a direct feed ammeter in the gauge panel, connected between the orange alternator output wire (that ran all the way to the panel) and the red battery wire. In the older version both the red and the orange wires were 8 gauge. Even though at first glance it appears to be an MMI drawing, some of the drawing modifications were by a forum member for his personal boat and properly removed any reference to Moyer Marine.

The modification did away with the voltage robbing ammeter in favor of a volt meter, the orange alt output wire was rerouted and the red wire reduced in size along with its fuse. In the previously posted drawing please notice that the 20 amp fuse in the purple ignition wire does not protect the gauge wiring. That protection is provided by the 20 amp fuse in the red battery wire.

However, the drawing is not representative of the MMI engine rewiring kit available in the online catalog. The red battery wire is 8 gauge and fused at 40A to handle multiple loads (ignition, starter solenoid, possible fuel pump, etc.) and the ignition wire is fused at 20A. It also returned the option of a direct wire ammeter and although we on this forum universally advise against it, you still have the option.* The drawing posted previously has been updated/corrected and I've included it here. Sorry for the quality, I took it off a screen shot.

*Note: opinions expressed on the forum are not necessarily endorsed by the host.

[wallis]

file not found

Sounds like you have the older style of wiring, which works but requires long runs of alternator output cabling. When I rewired the boat, I chose instead to run a short properly sized red cable from the alternator's "output" post to the big battery cable post on the starter solenoid, where a big red cable is attached that runs directly to the positive post on the engine start battery. That allowed me to replace the ammeter in the ignition panel with a voltmeter, to simplify the ignition system wiring, and to separate the house from engine circuits. In the old way on C&C's, power for house circuits came from the ignition panel, because that's where the alternator output ended up, so there were much longer wire runs than I have now for the house circuits, and house and engine circuits were not separated.

There are some interesting threads on this forum on wiring - try searching on "schematic". Examples:

http://www.moyermarine.com/forums/showthread.php?t=2727

http://www.moyermarine.com/forums/showthread.php?t=2685

http://www.moyermarine.com/forums/showthread.php?t=1341

http://www.moyermarine.com/forums/showthread.php?t=2580

It is unfortunate that so many of the threads referred to in posts are no longer to be found.

[ndutton]

It is unfortunate that so many of the threads referred to in posts are no longer to be found.

It's a carry over from when the forum changed servers. All you need to do is add 'forum' after 'moyermarine' in the address bar of the link (using the first link in your post as an example) thusly:

https://moyermarineforum.com/forums/showthread.php?t=2727

[wallis]

finding old links

I believe it would be very helpful to new users to include this information in the "new member" faq. There has been many occasions when "not found" has popped up on me when using the links in messages. Too much great information has been accidentally hidden by the change. Many thanks to you for informing me about this.