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MG MGB Technical - Dash mounted Voltmeter

I would like to add an under dash voltmeter to my 67' GT. I don't want to go to Pep Boys or such for a gauge that won't look right. Any ideas on where to purchase a "period" instrument or what British car had a gauge that I could work with?
Thanks...Steve
Steve Brooks

Try a Triumph Stag or other Triumph's of a similar period to your MGB.

Peter
P L Hills

Steve - Try Smith Guages at http://www.gbinstruments.com/
or VDO at http://www.vdona.com/performance. Both carry voltmeters that will look good in a 67 MGB. The Smith guages will match the original guages in the MG, while the VDO guages can be orderd through local auto parts dealers. I put a VDO clock and voltmeter in my 67 MGB, using a mounting supplied by VDO and mounted them on the transmission tunnel just in front of the speaker.
Good luck - Dave
David DuBois

I just checked the GB Instruments website and they say they have severed ties with Smith Gauges (click the "What's New" gauge on the left).
Marvin Deupree

Steve;
I purchased new Smith's gauges; volt & amp for my Healey from Nisonger Instrument in New York.914-381-1952,or www.nisonger.com . A little pricey, but really nice.

Pete Haburt
Pete Haburt

Why bother with a volt meter? They don't seem to perform a useful function. Its a bit like having a light on the TV telling you that it is on.
philip may

One of the most useful gauges you can add to your MG. The voltage indicates problems with the electrical system before you are left along side the road.
Alternator equiped system should run about 14.4 volts.
Not running your battery should be just over 12 volts.
Cranking voltage should not drop below 10.5 volts (10 seconds);
below 10.5 the battery is getting tired. Load test is the only good
test of the battery.
Leland Bradley

I think Jag XJ6's had a Smith's voltmeter that matches well. I see hundreds of them in the boneyards.
Paul Konkle

Steve,

Gower Oaks stock the classic Smiths gauges, including the voltmeter to match the existing gauges. http://www.gower-oaks.co.uk/

Geoff
Geoff King

Jag XJ6s from '71 on and probably before had a gauge panel that looks exactly like what you'd want, except the gauges aren't in their own individual cans. They have all the gauge internals connected up to a harness and so forth; the whole works is then covered with a plastic cover. Not what you want, I found out the hard way. I don't know when they went to that system from each gauge being self contained, but be careful.
Wade Keene

Thanks everyone..The websites listed in this thread are cool, just what I was looking for!!!
Steve Brooks

A voltmeter is no more use than an ammeter, although it is safer to wire and is less likely to cause problems. Neither tell you any more than a functioning ignition warning light. And none of them can tell you if your car is going to start in the morning.
Paul Hunt

Paul..point well taken, although to me there is nothing better than scanning the dash of my GT while driving and reading those great Smith's gauges for "system status".
Steve
Steve Brooks

My 73 B has one and I wouldn't be without it. A club member has had a number of alternator failures which were noticed immediately via his voltmeter reading dropping whilst the red light stayed off. To me it is as comforting as the oil pressure gauge during normal driving - scan oil pressure, temperature and voltage.
Barry Quartermaine

In the alternator equipped midget I had years ago, I installed an ammeter. The red light glowed faintly nearly all the time, but the starter spun around fine most of the time. The ammeter could tell me with accuracy what the charging system was actually doing all of the time, and thus give some warning as to whether I would need to get a push start or whether I should be paying attention to the red light at all. As it turned out I totalled the car before I could find out just exactly was causing my problems, but having a more accurated/precise indicator of my charging system was extremely useful.
Wade Keene

Can I just confirm my understanding of this?
With the ignition on and the engine not started the ignition warning light is red, powered by battery voltage, right? With the engine started (assuming the charging system is working) the warning light goes out - the battery voltage is "overcome" by the higher voltage from the dynamo or alternator and the current does not flow through the ignition warning light. So for a dynamo or alternator to fail and the ignition warning light to stay off suggests that the failure of the d/a must be gradual, not sudden and total? If gradual, the battery voltage would run down and the ignition warning light would start to glow and gradually get brighter, wouldn't it.

I can see how a voltmeter would be helpful but I am not sure how it would help spot a problem coming that the ignition warning light wouldn't?

richard
Richard Atkinson

I have a volt meter fitted, it shows you the voltage in the system, at idle with a dyno its around 12 volts, at running speed 15, so it just shows that the dyno and voltage regulator are working, bit of fun for a few pounds.
Tatty

Steve, Check with Tony Barnhill at theautoist.com
He might have a good used one in stock. Has a lot Brit & mg spares - Mike
Mike

Richard - the first part of your understanding of the ignition warning light is correct. But once the alternator is charging the warning light has the same voltage, now about 14v, connected to both sides and this is why it goes out. If the alternator stops charging for a variety of reasons the 14v from the alternator to the warning light is replaced by a ground and so the warning light comes on brightly immediately. A dim warning light, expecially if it brightens as the electrical load is increased, is usually caused by one or more bad diodes in the alt. Depending on which ones and whether they are short or open can result in lower output voltage, lower max current, increased heat, noise, or various combinations of these.
Paul Hunt

This thread was discussed between 11/05/2002 and 16/05/2002

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