Adding an Ammeter

[AN6-TX]

I know it's JUST an old MGB, but I made a console to add a period correct looking voltmeter and clock. The voltmeter gives enough feedback to know what's going on with the electrical system. This car ('65 MGB roadster) was converted to negative ground and an alternator.


View attachment 94419

What do the toggle switches (below the added gauges) do?

 

[Lotuswins]

I had an Ammeter in my car for years but didn't like the idea that they drew such a high current so I replaced it with a Volt Meter.
When I removed the gauge I noticed the wires had turned black about an inch down the insulation from where they were attached to the back of the gauge !!! I feel safer now.
Bouna fortuna,
Peter C.

Peter,

Your ammeter must have had the spade connectors? The large ones, rated at something like 35 amps, can after a long time work loose from vibration or loom movement creating resistance in the connection, which will heat the connector which causes the metal to anneal, which makes more resistance, etc. you get the idea. It can eventually cause a failure or possibly a fire in the worst case. Periodic checking of the connectors should be done on these old cars to insure they are still tight and there is no evidence of localized heating at the ammeter. I had evidence on my Europa so I converted to ring tongue lugs with lock washers. Note that when converting to an alternator you can easily exceed the amp rating of these connectors.
I personally prefer an ammeter to a voltmeter but both are useful. The ammeter gives you quantity of current flowing so you can evaluate if things are normal or not. Voltmeters, at least to me, are more vague in what they are displaying. Of course both is the best of all worlds. You can now get LEDs that will display different colors based on what voltage is connected, really cool and not hard to connect nor is it invasive to your original look.

 

[DrEntropy]

What do the toggle switches (below the added gauges) do?

(L. to R.) 1: Electric radiator fan override (Florida traffic). 2: A switch to go from stock horns to air horns (also Florida traffic!). 3: Courtesy lamps under-dash.

 

[PAUL161]

Does anyone use their horn? Once in a while, maybe once in 6 months or so, I toot the horn to see if it/they still work! Yup, they still do!

 

[tahoe healey]

Darn right I do! I got to let those huge pick-up trucks on steroids know that I'm down below their side view mirrors. ('Couse they can 't see my middle finger)

 

[Bob_Spidell]

I hit my BN2's horn button getting in or out of the car every once-in-a-while; startles the crap out of me as they are twice as loud as my BJ8's.

 

[petnatcar]

I tried to find any articles dealing with the issue but couldn’t find anything.
I’m going to add an ammeter to my Austin Healey 100-6. Can anyone recommend the best way to accomplish this?
Regards
Roger

I had an Ammeter for a long time but after noticing the connections on the back of the gauge turned black from over heating I decided to install a Voltmeter. This doesn't require as much amperage and works just as well.

 

[Editor_Reid]

I had an Ammeter for a long time but after noticing the connections on the back of the gauge turned black from over heating I decided to install a Voltmeter. This doesn't require as much amperage and works just as well.

Nice job with the instrument cluster! It really "looks the business," as the Brits say.

Pro Tip: If you ever decide to sell, rotate the tach back to its normal orientation. Rotating it so that the redline is at 12 o'clock as it is now, as seen in race cars, suggests the driver winds up the engine to near redline a lot