wiring ammeter question.

[chincha805]

i am at the point of installing my wire harness and stuck at the ammeter gauge,
i have a 1949 AD PU , using 12v stock D C gauge with a one wire alternator using a EZ Wire harness. my question is , do i run the 10g starter wire from the fuse panel to the ammeter gauge positive or negative ? then from the ammeter to the starter? i dont quite get the ez wiring instructions.

[Wrenchbender Ret]

You run the 10 gauge wire from the bat cable at the starter to the pos. term. on the meter. The neg. goes to the various feeds. It is a good idea to put a fuseable link at the starter connection. It you have it backwards on the amp. meter the guige will work backwards. Reverse the connections.

[_Ogre]

imo... the 1-wire alt is 100 amp or larger; the oem amp gauge is 30 amp
i'd bypass it totally by running the 1-wire alt direct to the battery or main starter lug
and feed the ez wire harness straight off the battery bypassing the ammeter
the risk is letting the smoke out of a brand new wiring harness if the oem ammeter has a meltdown

you maybe able to convert the ammeter to a voltmeter, similar to what i did on my 58
read how i did it in my build, it was ez enough to do

red insulator

[franken]

Could cook the Ammeter not the wiring. It would act as a fuse... Zot.
Might be able to replace the shunt on the ammeter and give it greater capacity. Most use a Voltmeter. I don't know what the gauges look like on those.

[spectral]

I agree with above .. I'd try and convert it into a voltmeter if possible. Ammeter is not that useful and I hate having heavy gauge wiring into the dash...bzzt.

[chincha805]

is it possible to use the stock ammeter, and use a volt meter in a different location, my goal is to keep stock look?

[chincha805]

after ready other info on ammeter issues fires etc, , i think i will decide to leave the ammeter in place stock location dead, and install a voltmeter gauge

[chincha805]

just a thought, i have a one wire alternator that is 60 amp, i also have a stewart warner ammeter that is 60-0-60. couldn't i change out the internals from my stock ammeter with the new 60-0-60 ammeter internals, the screw holes line up almost perfect.
what do you think.?

[Daze57]

chincha805

if i am not mistaken ogre in his build thread did a ampmeter to volt meter conversion fo his 58 truck -- you may want to check it out --- it may be just the thing for ya
i think its starts on # 38 in his thread
hope this helps

[_Ogre]

that's what i did. the swing needs to be the same (ie 70*, 90* or 120*)
i left my face plate alone and cut the stock needle off and glued it to the new gauge
off the needle is at D, at 12v+ the needle is centered and 14v+ the needle is to the right of the center

off (needle to the left)



running down the road (needle just to the right of center)

[chincha805]

thank ya'll for the input. i ended up changing out the internals of the stock ammeter and put in the internals from a volt gauge in the stock guage cluster like Ogre did.

[_Ogre]

document the process and post up some pics
when i posted what did my tf ammeter it generated a lot of interest
i'm sure the ad crowd will be equally interested

[OrrieG]

Now you guys have be worried. I have a 65A 3 wire alt, before had the stock generator. I just wired thru the ammeter, so far it has worked ok on the short running time, max 5 minutes or so most at idle. Is that going to be an issue or is there enough risk to dive back into the wiring and change it. Not concerned about the gauge function, the old one (replaced the cluster) did not work. From the posts above it sounds like I can just disconnect the wires from the ammeter, connect them together, shrink wrap to prevent arcing and be good?

[Second Series]

I have the original ammeter in my '47 panel with a one wire alternator and it works fine even with some original cloth covered wire! It's been like that for a couple decades now.

[Russell Ashley]

Orrie, I don't think you have anything to worry about. Look at the rear of the amp gauge. The current from the alternator goes through that brass plate and it is more than sufficient to handle the load. Nothing actually passes through the windings of the gauge, it is moved by the field that is created around the brass plate. There are extra tabs on the gauge. I put a jumper across the two bottom ones to divide the current and lessen the field to keep the gauge from pegging. It has worked fine for about four years now.

[OrrieG]

Thanks Russ, from ogre post it sounded like circuit with thru the gauge itself. I will leave it be and know were to look when the lights go out...

[_Ogre]

i've run 1 wire alternators thru the amp gauge for years
then one time a flash caught my eye going down the road
i was looking at the gauges the next time it sparked near the corner of my ammeter
next thing i knew the cab was full of smoke, i had let the smoke out of the wires
it cost me some serious burns on my hand as i reached under the dash and pulled the smoking wire out

yes it may work for years, or it may let the smoke out of the wires tomorrow
if your doing a complete rewire... bypass the ammeter

[Russell Ashley]

"yes it may work for years, or it may let the smoke out of the wires tomorrow
if your doing a complete rewire... bypass the ammeter"

I disagree that you need to eliminate the amp gauge if you have new wiring and add the jumper. Needless to say, the slip on connectors must be tight on the tabs, but this is just common sense and applies to every connection. IMO If you saw a spark there had to have been a loose connection, or something touched something that it wasn't supposed to touch.