Hazardous Wiring

[jim wagner]

I have installed one of Scott's air pumps on our GMC and decided to wire
it directly to the battery using a circuit breaker and relay. On our GMC
the front battery is connected to a lug that is on the firewall. I ran a
two inch long piece of wire from this lug to the circuit breaker then to
the relay.
What I found attached to this lug were four extra wires that the P.O.
had added. One wire went to the CB, one to a switch for a set of fog
lights, one was cut and taped and the last one was cut and lefl inside
of the dash.
I have removed these wires from the lug and will rewire the CB to a
fused connection.
My point in bringing this up is that none of these wires were protected
with a fuse or circuit breaker. Since most of our GMCs had P.O. I would
suggest that you take a look at your wiring to make sure this hazardous
wiring has not been done to your GMC.
The other Jim 76GB500Cad

 

[jim bounds1]

The other Jim,

You are very right, I run into stuff you would not believe.

The absolute rule is to fuse protect every circuit added as close to the
source as possible. I would also try to not gang up on draws. I try to
have a dedicated (home run) circuit & breaker or fuse on each.

I saw where someone had bypassed the 120 amp circuit breaker protecting the
2 ga. wire headed to the generator- talk about scarey.

Great point, please take great care when wiring 12 volt circuits.

Jim Bounds
- --------------------------

>I have installed one of Scott's air pumps on our GMC and decided to wire
>it directly to the battery using a circuit breaker and relay. On our GMC
>the front battery is connected to a lug that is on the firewall. I ran a
>two inch long piece of wire from this lug to the circuit breaker then to
>the relay.
> What I found attached to this lug were four extra wires that the P.O.
>had added. One wire went to the CB, one to a switch for a set of fog
>lights, one was cut and taped and the last one was cut and lefl inside
>of the dash.
>I have removed these wires from the lug and will rewire the CB to a
>fused connection.
>My point in bringing this up is that none of these wires were protected
>with a fuse or circuit breaker. Since most of our GMCs had P.O. I would
>suggest that you take a look at your wiring to make sure this hazardous
>wiring has not been done to your GMC.
>The other Jim 76GB500Cad
>
>
>

 

[blank]

>
> My point in bringing this up is that none of these wires were
> protected with a fuse or circuit breaker.

Somewhere along the line, a PO added a 4ga jumper from the house battery to
the genset battery on my coach. A 30ft length of cable without a breaker or
fuse on either end. I promptly disconnected it when I found it and will be
installing fuses on both ends.

Patrick

 

[emerystora]

>>
>> My point in bringing this up is that none of these wires were
>> protected with a fuse or circuit breaker.
>
>Somewhere along the line, a PO added a 4ga jumper from the house battery to
>the genset battery on my coach. A 30ft length of cable without a breaker or
>fuse on either end. I promptly disconnected it when I found it and will be
>installing fuses on both ends.
>
>Patrick

Patrick - when GMC used a wire between the batteries they used a 1
gauge wire and it connected to the boost solenoid in the front and
then to the battery isolater. The 4 gauge is not really heavy enough
if you are going to use it to start the engine. The 4 gauge should
be ok for normal charging with the addition of a circuit breaker. In
the rear it is connected to a circuit breaker (I believe 50 or 60
amp) so that the charging current through the battery isolator had a
protected circuit. The rear also had a solenoid that bypassed the
circuit breaker when the boost switch was pushed as the starting
current might exceed the 60 amp breaker's capacity.

This is shown on the wiring diagrams of the newer models.

Emery Stora
77 Kingsley
Santa Fe, NM

 

[blank]

Emery,

I've got a 73, which has 3 batteries. Coach and House in the front and
Genset in the rear. The configuration you refer to was when they eliminated
the Genset battery and moved the House battery to the rear. I'm not sure
why the 4ga wire was used, but I plan to keep it for charging(and jumping)
the Genset battery off the Coach battery - never the other way around. If
the Coach battery needs a boost, it'll get it from the House battery.

Thanks,
Patrick

> >
> >Somewhere along the line, a PO added a 4ga jumper from the
> >house battery to the genset battery on my coach. A 30ft
> >length of cable without a breaker or fuse on either end.
> >I promptly disconnected it when I found it and will be
> >installing fuses on both ends.
> >
> >Patrick
>
> Patrick - when GMC used a wire between the batteries they used a 1
> gauge wire and it connected to the boost solenoid in the front and
> then to the battery isolater. The 4 gauge is not really heavy enough
> if you are going to use it to start the engine. The 4 gauge should
> be ok for normal charging with the addition of a circuit breaker. In
> the rear it is connected to a circuit breaker (I believe 50 or 60
> amp) so that the charging current through the battery isolator had a
> protected circuit. The rear also had a solenoid that bypassed the
> circuit breaker when the boost switch was pushed as the starting
> current might exceed the 60 amp breaker's capacity.
>
> This is shown on the wiring diagrams of the newer models.
>
> Emery Stora
> 77 Kingsley
> Santa Fe, NM
>

 

[emerystora]

>Emery,
>
>I've got a 73, which has 3 batteries. Coach and House in the front and
>Genset in the rear. The configuration you refer to was when they eliminated
>the Genset battery and moved the House battery to the rear. I'm not sure
>why the 4ga wire was used, but I plan to keep it for charging(and jumping)
>the Genset battery off the Coach battery - never the other way around. If
>the Coach battery needs a boost, it'll get it from the House battery.
>
>Thanks,
>Patrick
>

Hi Patrick - and I am the one who just recently posted a reminder
that new readers have to be aware that there are differences from
model year to model year and what applies to one doesn't necessarily
apply to another model year!

Guess I should remember my own advise!

Emery Stora
77 Kingsley
Santa Fe, NM

 

[chuck sankey]

One of the first surprises I had was with the house wiring. As soon as we
got the "Pickle" the front dinette came up and I found badly frayed wiring
for the wall 110V outlet. The area that was worse was the area were the wire
transverse across the front at the first step. If at any time you have the
forward dinette seat up check it out . There must be flexing at that corner.

Chuck Sankey
Palm Beach '76
Central Ohio
csankey1