Need advice How to Install a volt gauge properly

[drambuie]

Hello everyone, I would like ask, what are the proper connections when installing a volt gauge to a 67 BJ8 with positive ground. I have been searching this topic, however I was not satisfied with the advise....so, I will pose the question if anyone here cares to make a suggestion.

I would think the hot wire "white" from the ignition switch would be connected to one wire in back of the gauge, and the other wire from the gauge goes to ground. Any need for a in line fuse between gauge and white ignition wire? Naturally, I want the gauge to shut off when the cars ignition is turned off. Thanks everyone and have a Great Thanksgiving.

 

[andrea]

https://mgaguru.com/mgtech/electric/et220.htm here you can find a great technical and practical article
my easy and cost cut solution
Voltmeter on car is a good auxiliary info
-BUT Amperometer are more useful

 

[drambuie]

Thank you for the article and electrical schematics Andrea.... Most helpful, I will use a smiths gauge so it matches the other smiths gauges. I was reading a article that Amp gauges draw high current and can cause fires if not wired properly under the dash. That is why many people tend to go with a volt gauge. I think 16 gauge wire should be ok for the volt gauge wiring. Michael.

 

[andrea]

wire for voltmeter are NOT critical and you can use the normal wires
for the Ammeter gauge, are very critical - all the current for lamps headlamps fan relays etc. transit through it, for measurement of absorption
Cheers

 

[drambuie]

Thank you again Andrea, I really appreciate your advise on this subject. After installing a new Control box"regulator" I thought it would be a good idea to have a volt gauge to monitor the battery condition. Take care, Michael.

 

[Keoke]

wire for voltmeter are NOT critical and you can use the normal wires
for the Ammeter gauge, are very critical - all the current for lamps headlamps fan relays etc. transit through it, for measurement of absorption
Cheers

Addirionally if the Ampmeter fails you are out of power on the car------

 

[Patrick67BJ8]

Addirionally if the Ampmeter fails you are out of power on the car------

True, unless you install a "shunt". (I think it's a shunt but it could be called something else??)

 

[John Turney]

Ammeters include a shunt. They work by measuring the voltage drop across the shunt.

 

[steveg]

I had a situation where the car ran out of electricity and stopped dead on a freeway due to my inadvertently having disconnected the field wire from the alternator. The car had run for a couple of weeks in the daytime with my having no idea the alternator wasn't charging the battery!
I installed the Moss Smiths voltmeter in parallel with the ignition switch wire to the coil. Very easy.
Now I can look and see 13.5 volts when the car's running. So I can easily tell whether my alternator's charging or not.
Am inclined to favor the voltmeter due to ease of installation and, I think, superior info. Ammeters have given way to voltmeters on modern cars.

 

[tahoe healey]

Why not use both the ammeter and voltmeter? Easy to do and each has it own information. (and I like watching the needles move) It is interesting to watch the ammeter when you have the radio, directional signal and lights on.

 

[Patrick67BJ8]

Why not use both the ammeter and voltmeter? Easy to do and each has it own information. (and I like watching the needles move) It is interesting to watch the ammeter when you have the radio, directional signal and lights on.

With all that needle watching when do you find time to text when you're driving?

 

[John Turney]

With all that needle watching when do you find time to text when you're driving?

It comes naturally to Californians!

 

[drambuie]

Ok....now that I have the the right connections, white ignition wire to volt meter and the other volt meter wire to ground...anyone have a good smiths volt meter "black face" they want to sell?

 

[Keoke]

You will still go dead in the water if the ampmeter fails--TH---:friendly_wink:

 

[Patrick67BJ8]

Ok....now that I have the the right connections, white ignition wire to volt meter and the other volt meter wire to ground...anyone have a good smiths volt meter "black face" they want to sell?

Check ebay. They popup often.

 

[steveg]

Ok....now that I have the the right connections, white ignition wire to volt meter and the other volt meter wire to ground...anyone have a good smiths volt meter "black face" they want to sell?

See:
https://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=69858&SortOrder=10

 

[tahoe healey]

Well, I have my wife hold my beer.
Keoke, I have shielded the wire where ever the go near any other wire or firewall. Is it more likely to fail than any other Lucas system? I'm pushing 4 to 5 years on the system. If I should have a road side problem, the gauge could be by passed easily. No? I think an ammeter is the most valuable gauge (with the acceptation of maybe the pressure/temp gauge)as I have driven without a tach and with a speedo registering all over the place. We won't even discuss the accuracy of the fuel gauge.