new gauges

disra · Post by **disra** » Sat Jul 14, 2007 2:30 pm

im stumped i took out the factory gauges in my 69 d100 and everything worked. now im trying to put in the new aftermarket ones and i have no juice my headlights or blinkers wont even work. any suggestions?????

disra

Jeffc · Post by **Jeffc** » Sat Jul 14, 2007 4:23 pm

the 2 red wires that were on the back of the alt gauge
need to be connected to each other
(take a small bolt and nut and clamp them), or to a gauge that will pass voltage/amps to the starter relay/battery.
One of those red wires will be hot from the battery
though the starter relay.
The other red wire runs though the fire wall to
the alt (will be black on the engine side of the
fire wall) and has a splice that powers the key
and every thing else unber the dash.

If the above is not done the battery and alt will
not supply power to anything under the dash.

The aftermarket voltage gauge can then be hooked up
as per instructions.

disra · Post by **disra** » Sat Jul 14, 2007 5:58 pm

thanks jeff it worked like a charm im in debt to you. thanks again

Jeffc · Post by **Jeffc** » Sat Jul 14, 2007 6:38 pm

just glade it's working

reallylongnickname · Post by **reallylongnickname** » Tue Aug 14, 2007 7:57 pm

I am wondering about my factory fuel and volt gauges. volt has 2 nuted posts. Then there is some kinda bridge connecting the 2 gauges. Doesn't seem to be a ground. Wonder what it is. Would not be a positive. B post is positive bus. S is send. What is A?

Jeffc · Post by **Jeffc** » Tue Aug 14, 2007 11:47 pm

reallylongnickname wrote:I am wondering about my factory fuel and volt gauges. volt has 2 nuted posts. Then there is some kinda bridge connecting the 2 gauges. Doesn't seem to be a ground. Wonder what it is. Would not be a positive. B post is positive bus. S is send. What is A?

The power feed (red wire) to your fuel gauge from the switch
is plugged into the bar (buss bar) that crosses the back of the alt guage. All the plugs on that bar can be used
to feed a switched 12v supply to what every you want to
add to your truck (within what the feed wire can supply
without cooking).

S (sender)is from fuel tank sender
A (accessory)is power to the temp guage (reduced voltage from the voltage limiter built into your fuel
gauge)
http://imageevent.com/jeffc/techstuff2e ... =4&s=0&z=2

reallylongnickname · Post by **reallylongnickname** » Wed Aug 15, 2007 3:18 pm

Thx Jeff. Geez that's a good detailed answer. Remind me to leave a tip in the tip-jar on my way out.

reallylongnickname · Post by **reallylongnickname** » Wed Aug 15, 2007 3:33 pm

When u say "alt gauge" did u mean volt gauge. Im guessing alt gauge might be for a generator.
The two posts on the volt meter, if one is a reduced pos feed from the fuel gauge, and the gauges are grounded when screwed into the gauge cluster, what then is the 2nd post on the volt gauge?

Jeffc · Post by **Jeffc** » Wed Aug 15, 2007 4:52 pm

Unless the gauge has been replaced it is a ALT gauge.
The alt gauge is a ammeter and reads amps not voltage.

The last year that Chysler used a genarator was
back in 59, if I recall, from the factory; one of
the frist to change over in the US: 1960 from
on- all alternators (unless special order. special use).

A alt gauge needs the two posts because power passes though the gauge from the altenator to the battery.
Power from the battery or alt is always passing one
way or the other though the guage.
All mopars, cars and trucks, use a alt gauge, not
a voltage gauge, from the factory in the 60s and early
70s.

Power from the alt to battery will show as +
if system use is low enough to charge the
battery.
Power from battery to system shows as -
if system use is higher than what the alt
can make.

If your gauge face says volt gauge then it is wired
differant than a Alt gauge. A voltage gauge will
not have the full power of the alt running though it.

Amps and voltage are related, but not the same.
You can have a 12 volt system that is able to make
a max of 35amps (stock to many of the 60s trucks)
or a 12 volt system that has a 100+ amp system
(most newer cars/trucks have 100amp or higher output
alts, since the amp draw is much higher with all the
garbage they use (i.e. computers, power widow, power seats, pumps, fans, ect.)).

What any one system will make depends on what a alt will make in amps and what the wires will handle without cooking because the amps are too high, not
the voltage.

reallylongnickname · Post by **reallylongnickname** » Wed Aug 15, 2007 8:05 pm

Dam, Im a fool. It is ALT gauge.

Jeffc · Post by **Jeffc** » Thu Aug 16, 2007 12:59 am

Not a fool, just didn't read your gauge right....

reallylongnickname · Post by **reallylongnickname** » Fri Aug 17, 2007 9:10 am

My alternator is not stock. It is a 65 amp. I dont know how the previous owner had the alt gauge hooked up, but it was all a big messy nest of wired. 120v breaker boxes and every thing. So I put in a new wiring kit.

Anyway it sounds like I cannot hook up the alt gauge because the amps are too high. Or would be a head ache hooking it up. Its pretty much already set up to hook to a volt gauge. Is this true about being a lot of trouble trying to make this alt gauge function just to have the "tradition" of it.

Jeffc · Post by **Jeffc** » Fri Aug 17, 2007 5:18 pm

If you wish to wire the gauge in with the 65 amp
alt it should be just fine with just about any year
of our trucks (even the ones that came with the 35amp
alt). It's when your going over 70+ amps that the
old 35amp wiring starts to become a worry.

However:

If you choose not to use the alt gauge-- then bypass
it and go directly to the starter relay and then
wire a voltage gauge into the system.
The only trick you really need to be aware of doing
this is- the alt wire, that comes to the alt gauge,
supplies the hole system by a splice that goes
to the key and headlights, so it needs to have a
12v supply conected to it back from the battery.
Otherwise nothing will work......

Two ways to do this bypass of alt guage (still need to
add a voltage gauge)
One way to do this---
bolt the two wires that attach to the alt guage
together,
other way----
do the above, but also run a wire strait from the
alt to the battery (this is the best way if your
going to use a alt that has over 70amps).

Ether way you will still have 12v power supply
if you leave the stock wires bolted and the
rest of the old stock system in place.