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Triumph TR6 - Ammeter Reading

I am trying to determine what would be considered a typical ammeter reading. I reviewed Bentley's pub but could not find any data. Mine runs around 12 on the guage and dips to the left when running lights etc. Not sure if this is a problem or okay.

Hi Shawn,
Use a good analogue or better yet a digital volt meter
(VOM) and measure across the battery with car off and you should read 12 volts...when the car is running the reading should climb to 13/14/15 volts depending if the battery is low. It will drop when the lights are on but will climb up when you rev up the engine.
If the ammeter still shows 12 then it's just not as accurate as it once was.

Charlie B.

Charlie, Thanks...the meter used to run up 13,14, 15 pretty constant but started to show 12 or less and does drop with lights on and gradually goes back to 12. I bought a new battery yesterday thinking this would get it back to the way it was (battery was 7 years old) but it still reads the same.


Ammeters don't show #'s. Just charge/draw.
Are you reading volts? As Charlie said 12,13,14 is good. is on the low side.


Thanks for responding. Yes I mean volts..the guage stays around 12 or a little less...goes down after initial start up or use of lights etc but goes back to 12. I raise the question because it used to stay around 14. I had the alternator rebuilt last Spring and have not had a problems.


Check the belt. But I would yank it and take it to the local auto store to test.

I would use a good voltmeter on the battery terminals to compare with your dash gauge. That will tell you more than anything. I guess you could check the voltage at the gauge terminals, too. If your starter is turning as fast as usual, you probably don't have a problem. But a long night trip might prove me wrong. Corrosion of connectors is one of the most common things that make people cuss Lucas.

I was lookimg over the Moss cat and now realize apparently older TRs had ammeters and looks like after 74 on that volt guages were used. My TR6 is a 74 and has the volt guage. Don....some of your posting did not come through. What were you saying for bad numbers?Shawn

IF your running 12 ,that is kind of iffy. Yank the alt. and have it tested.All the major auto stores do it.If it's bad upgrade to a Delco

This thread was discussed between 22/04/2007 and 24/04/2007

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