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Topic: Ammeter conversion to Voltmeter R&R guts (Read 3810 times) previous topic - next topic

Ammeter conversion to Voltmeter R&R guts

I just took out the guts of the amp meter and replaced with aftermarket insides.
works well so far, we bonded to the ign sw black light green for the time being by soldering to the terminal itself until we get the ign switch relay mod done.

works and looks just like oem.
depending on which aftermarket volt meter you get depends on how you go about it, just remember to "NOT" alow the ivr to feed the guage anymore but keep the mounting studs.  You can see how insulated the ammeter hold down nuts from the flex print so its not in the game.
We have a dedicated power and ground for the meter at this time.
Our plan long term is to have a 12 position rotary switch that can be set to pos1 to read alternator power, pos 2 to read battery, pos 3 to read 5v ivr and the remaining positions would be downstream of the fuse links.  This way if every there is an electrical issue and the volt meter is working, its already bonded to stratigic test points to help eleminate circuits.

i found it to be easy to vise grip to and heat up a razor blade in order to remove the ammeter cover from the housing itself..
The hardest part is to install the new insides such that it sits at the correct height so when the needle is installed, it does not rub the face.

one thing that i struggled with was were to place the needle representing "off" or zero volts, in the end we decided to allow the full needle swing to happen so that the needle is just below "C" with the car running.  The needles goes well below "D" so i think i could measure and "see" 5vdc on the guage when the rotary switch is installed later.

Ammeter conversion to Voltmeter R&R guts

Reply #1 –
here are a few more pics

Ammeter conversion to Voltmeter R&R guts

Reply #2 –
a few more pics to see

Ammeter conversion to Voltmeter R&R guts

Reply #3 –
got asked about "how to"

-purchase aftermarket volt meter (i got mine from tractor supply)
-remove cluster, cover and face
-remove two nuts on rear of amp meter
-remove and save ammeter needle
-place razor blade in vise grips, heat blade and cut along area where amp meter top cover is attached to bottom
-lift out ammeter coil winding and snip off the two wires flush as possible down at mounting studs down inside your housing

New volt meter
-take it apart and get the coil assembly out of the housing, discard all other parts.
-coil assembly should have a + and - terminal studs and a third stud you can ignore.
-place coil assembly inside your old ammeter housing keeping in mind proper orientation
-you can use a drill bit and spin it by had to make the holes so your new coil can now drop into your old ammeter housing.
-test fit cover with needle and determine your shim requiremets on the volt meter coil so its high enough
-add your aftermarket nuts to the back of the ammeter housing along with any thin washers you may need.
-trim excess off your volt meter + and - studs
-Test fit everything again to insure needle clears ammeter face cover then when ready, super glue ammeter cover to housing.
-round file the "top edge of the ammeter housing to make room for 1) ea red and black conductors
-solder a 6'' red to positive volt meter coil post where all the other stuff is soldered to.
-solder a 6'' black to the negative volt meter coil post where all the other stuff is soldered to.
-snip off the flat white section of your old ammeter needle and super glue it to the top of your after market volt meter needle....some tpuppies required.
-test your meter on your car battery and reposition your needle as you desire to insure it acts the same when in the car.
install....
-place "voltmeter" back in instrument cluster
-make an insulation washer x 2 to install snug over volt meter mounting studs ( a single insulation span will also work)
-You do not want the ivr 5v to feed the volt meter anymore so this is why you need to insulate as my picture shows.
- round file the top right edge of instrument cluster to allow your 6'' wires to dress out.
-add a male and female bullet crimp connector to the ends of your wires.  (this way it cant be hooked up backwards in the future)
-install instrument cluster in a temporary manner
-unhook ign switch connector (if this is the area you plan to get power from)
-remove ign sw connector
-extract the black / green wire from ign switch connector
-add enough red wire to reach the black/ green wire at ign switch, extract this wire and solder directly to the black/green terminal along the crimp.
-add enough black wire to reach a good chassis ground near / at your steering column heavy steel area.
-plug in your new wires to the new volt meter
-re-snap in the black/green wire into ign sw connector and plug back in the ign sw connector to ign switch.

Test
turn key to accy or run and volt meter should swing to the level that represents your battery voltage.

Ammeter conversion to Voltmeter R&R guts

Reply #5 –
oh yeah,, duh

well, what ever the situation, the studs would need isolated from the flex print connection.

not sure what i was thinkin there.

Voltmeter replaces Ammeter

Reply #6 –
Beautiful job, jcassity. I have cursed that useless ammeter since I bought the car in '88. It never tells you anything you don't already know by the flames coming out of the alternator. Your post inspired me to do something similar. I had the cluster out to calibrate the fuel gauge, and I saw that the post spacing on the ammeter was nearly identical to the dimension on a used voltmeter I had saved from a job years ago. A quick cut with a hacksaw removed the other half that contained the fuel gauge, and a bit of grinding had the light pipe resting securely against the inside of the cluster housing. I soldered brass nuts to the pin posts of the new gauge and soldered them to the circuit board. That and a bit of foam weatherstrip behind the bezel hold the new unit securely. Then I cut the wires from the ammeter terminals at the harness, leaving 6" pigtails. I soldered the negative meter lead to the common ground and the positive to the IVR 12V power (It had a black pigtail hanging there waiting for me!). I already have a 3-G alternator so the shunt wires were not being used. Illumination is excellent, very compatible with the other gauges. Only quirk is, the numbers and the word "NORMAL" are sideways and the acid will leak out of the battery icon. I can take that better than risking removing and reattaching the needle, which I considered to preserve the stock look like you did. I don't remember what Ford vehicle was the gauge donor, but it would have been better if it had threaded posts. The pictures show the details. Well, they would except I can only upload three of the five I wanted to show.
NOTE: After I got the car back to running condition, I discovered that the IVR 12V terminal black pigtail is no good. With engine running it gives a fluctuating voltmeter around 10V. I rewired the + side to an ignition power terminal at the fuse panel and now it works fine.

Ammeter conversion to Voltmeter R&R guts

Reply #7 –
[COLOR="red"][/COLOR]Hey, thanks for the props!, you did a good job yourself!

*************YOU REALLY NEED TO STOP DROP AND ROLL____>look at this thread before you put that cluster back in.
Here is where we solved the heat problem from that big ass resistor.
buy or get a soap stone from a friend welder of yours.. or lowes.


http://www.foxtbirdcougarforums.com/showthread.php?34327-buttstuffog-cluster-*solve-that-heat-problem*-on-the-big-3-long-reisistor&daysprune=365

also,
to post more pics,, just post a new thread so you can just add three more pics.

also,
i got my volt guage from Tractor supply because its orientation flowed correctly (polarity wise) with the old ammeter.
 

Ammeter conversion to Voltmeter R&R guts

Reply #8 –
i guess what i mean is that the tractor supply voltmeter rotated in the same direction as the old ammeter.  when car is off, the needle is down,, when car is on, needle goes up to about 80% or so.

My plan is put a 12pos selector switch in series with the voltmeter (got at radio shack which is 12pos).
mount the selector switch in the dash.
have pos 1 wired to read battery like it is now.
have pos 2 > x read the downstream side of various fuse links.

have a couple positions wired to read  the tps. this way i can also move my gas pedal and see the needle movement and also since its buttstuffog, i can see intermittant opens in the TPS as well!!

have another position wired to any other critical circuit thats needed.

doing all this allows me to troubleshoot more efficiently.
there will be a tiny hole in the instrument panel like near where the power antenna switch is which i can insert a small jewlers and select all the positions to monitor power using my volt meter as my ,,,, well,, my volt meter!