Burnt Wire in harness from Control Panel to A4

[doogymon]

Hi

Can't seem to the Wiring harness kit part # on MM site.

Smoke from Engine Room. Shut her down. 80% Insulation burnt off one of the small gauge wires in the bundle leading from the harness plug on top of the engine (front)...back to the control panel (10 ft) . Haven't traced the termination point..yet..Typical wiring hack jobs that i haven't had a chance to clean up.

On the Black plug the insulation appears burnt off on the same wire on the engine side .

I will be jumping into the threads here to see how to properly wire (& fuse) the A4 (late model). Maybe I don't need a kit, just wire it up like the super schematic i saw here.

Oh yes..finding the fault first is paramount.

Doog

[doogymon]

Found the Kit

SKU: OVEL_01_394.

$230.00

Cheers

Doog

[JOHN COOKSON]

Hi

Can't seem to the Wiring harness kit part # on MM site.

Smoke from Engine Room. Shut her down. 80% Insulation burnt off one of the small gauge wires in the bundle leading from the harness plug on top of the engine (front)...back to the control panel (10 ft) . Haven't traced the termination point..yet..Typical wiring hack jobs that i haven't had a chance to clean up.

On the Black plug the insulation appears burnt off on the same wire on the engine side .

I will be jumping into the threads here to see how to properly wire (& fuse) the A4 (late model). Maybe I don't need a kit, just wire it up like the super schematic i saw here.

Oh yes..finding the fault first is paramount.

Doog

I like the idea of wiring with no plugs between A and B. The plugs will get corrosion on the contacts where the two parts join. This an be prevented by wrapping the join with electrician's tape to keep moisture out. Here's a wiring diagram.

ex TRUE GRIT

[doogymon]

Hi

JC thanks for the great schematic (nice format).

Found the suspect burnt wire with ring solderless terminal near the distributor, able to touch ground via the A4 block.

The wire was connected to the 13.8v multiplier terminal block at the remote control panel on one of the lugs.

The bare end was on the loose at the engine end and took the system to ground.

Process of elimination to see what the wire was used for ended up with no clue except:

Appears a few bells and whistle add on kits were installed then disconnected.

Not sure if any required 13.8v from the I terminal on the starter switch.

I strongly dislike rogue wires and especially un-terminated ones that have voltage on them.

Lots of other scary wiring discovered..!

Going to build a new harness (some of the wires in the bundle took large heat). May delete ammeter and replace with voltmeter. May go with push button start and separate Ign switch located in a place that will force me to do a visual and check the dang oil (not that there is a problem. Going to use terminal strips vice connectors.

So far has been a great kick in the a$$ to get boned up on all things igniton/elec for the A4.

Hoping no internals damaged.

TY

: )

I like the idea of wiring with no plugs between A and B. The plugs will get corrosion on the contacts where the two parts join. This an be prevented by wrapping the join with electrician's tape to keep moisture out. Here's a wiring diagram.

ex TRUE GRIT

[JOHN COOKSON]

Hi

JC thanks for the great schematic (nice format).
So far has been a great kick in the a$$ to get boned up on all things igniton/elec for the A4.
Hoping no internals damaged.
TY
: )

Just got the record that schematic is from my original A4 owner's manual.

When I rewired all end connectors were crimped, soldered, and heat shrunk. Also a single wire with no plugs A -> B The wiring was bullet proof. It paid off. When ever I had problem I knew it was not due to the wiring.

ex TRUE GRIT

[ndutton]

Do you notice anything missing in the wiring diagram? It's why your wire, once there was a problem, was destroyed.

Unfused engine wiring.

Compare this Moyer Marine wiring diagram:

[doogymon]

Hi NDutton

Yes yes....missing fuse holders (and fuses).

Which schematic should i use :

The one you posted

or

this one with 12 ga wire and an 8 ga orange wire b/w Alt O/p and + post on Solenoid?

I kind of like the smaller gauge wire. But can it source blower, guages, lamps etc?

TY

[ndutton]

You are approaching this the right way with an eye on the total system and asking the right questions. The answers may seem daunting however. Here are a few considerations as you decide what is best for you and your installation:

1. Within reason, larger wire gauge is ALWAYS better.
2. Does/will your remote instrument panel have a direct wire ammeter or a voltage gauge? The answer has a major effect on wire gauges and fuse size.
3. Brush up on conductor properties regarding voltage drop, a significant factor in circuit design. Per the ABYC, NEC and good electrical practice, design to a maximum allowable 3% voltage drop. If voltage drop is new to you or overly challenging, we can help.
4. You will never go wrong following the Moyer recommendations. Remember, the Universal design included trailer plug harness connections (shown right on their drawing) that have proven themselves over time to be one of the worst designs known to man.

More reading:

http://www.moyermarineforum.com/forums/showthread.php?t=10582

[doogymon]

Hi Neil

Thanks comments.

Blue Sea calculators says 12 Ga is correct (Famps 15 ft @ 3%).

I'm going with a voltmeter at the control panel vice Ammeter.

Will install a shunt ammeter at a later date near the battery compartment

Also shooting for a push button starter so will need a separate Ignition Energizer switch.

So i am leaning towards the schematic with the 12 Ga wire.

Great having this forum.

Doog

[/LIST]
More reading:
http://www.moyermarineforum.com/foru...ad.php?t=10582[/QUOTE]

[ndutton]

Sounds like you’ve got it although I’m lost at what you mean by Famps. With no panel direct wire ammeter the orange and red 8 gauge wires are overkill.

[doogymon]

Neil

Blueseas funky calculation using Famps concept.

http://assets.bluesea.com/files/resources/instructions/6959.pdf

Cheers Thanks

Doog

[roadnsky]

Too funny!
I'm installing a new Blue Sea DC Panel this weekend and I had the same response as Neil when I saw FAMPS on their documentation.

I guess common words/terms we use had to originate somewhere!

[ndutton]

I think Blue Seas might be making up their own terminology to sound important. I've dealt with voltage drop calculations on electrical plans for over 40 years, plans that are checked by governing authorities and never have the terms foot-amps or Famps made an appearance.

[doogymon]

My new harness works great.

Been sailing last few weeks.

I have a nice new volt meter in place of the ammeter.

Also have a Push Button Ign switch along with the switch that energizes the coil.

There maybe a hidden switch as well...; )

I used nice terminal boxes to replace the original concept of having connectors.

Thanks to the skippers above and beyond for guidance and the forum.

When sailing is done I hope to get back to tending to my baby A4...: )

Doog