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Triumph TR6 - Voltmeter Variations

Seeking advice,

During a recent trip the voltmeter on my '76 TR-6 started to show some new and rather strange behaviour. After start up [gas/pit stop] the voltmeter would slowly climb into the red zone, ie super high reading, but only after 5-10 min. of running.This indication would remain for 4-5 min., then back to a normal position, however this would repeat several times before "settling down". Dan Master's good book does not help, nothing specific to be found.

Any thoughts? Voltage regulation function in alternator? or??

Thanks for any/all suggestions.


Try running a volt meter (Radio shack) in parallel to check the funtioning of the meter. If the meters do not agree then suspect the dash meter. If they agree then suspect the regulator/alternator. could be heat related. Does it do it when it is cold?

Thanks skikir,

Your suggestions sound like the way to go...will do.

Temp. does not appear to be a or cold.....all the same. It seems to be more a "start up" situation than anything else. In your opinion is the voltage regulation function of the alternator a potential [likely] problem area? If so, is in known to be an intermittent one?

Many thanks!


The regulator is integral in the Alternator. It could be a loose connection or a flaky regulator. Hard to tell. Because this is intermittant you may want to take it to a auto electronics shop on this one.


Many thanks------your advice is much appreciated!

Off to the auto electronics people [a parallel volt meter check shows identical readings]


Are all your connections clean? Maybe the alternator is trying harder than it would need to if the path were clear, so to speak, to charge the battery. You can take the car or the alternator to an AutoZone or equivalent store for a free test. But a good auto electric guy is indispensable, if you want to pay him. He can save you money, too. Instead of a rebuilt whatever, usually only a small part is the culprit. Like brushes or diodes in the alternator, a solenoid or even just contacts in a starter, you get the picture. But labor is expensive.

Went through this exercise for the past week. Battery was dead every morning even with battery disconnected ( do you see the light bulb over my head:) Off to Carquest for a battery load check. Result 2 dead cells. In goes the new battery.
Rick C
Rick Crawford

Tom...all connections checked first thing, no joy there.Good advice re an auto electric guy...just happen to have one in the area who is familiar with Lucas stuff. battery 4-5 weeks ago, hygrometer check shows all ok, [I disconnect the ground terminal when the car is not in use].On startup the engine spins like mad.......lots of grunt!!

While looking through the "spares" shelves {junk pile?] I came upon an alternator I had forgotten about,working well when I removed it some years ago. In it goes to see what happens, could be a good diagnostic procedure.

Thanks all!


This thread was discussed between 05/10/2005 and 07/10/2005

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