Do I have a battery light ?! '73Firebird

[ukdave]

Hi, can anyone help me please ?

Should there be a light on the guages for the ignition and the battery/alternator ? I do not see any, I just have "fasten seat belt" and "brake". I have the 160mph guages - on a 1973 Firebird.

If it helps, a picture of the interior is at : http://www.angieanddave.com/bird03.jpg

Why the silly/simple qustion ? I am in the UK - England so it is difficult to get info on other Firebirds easily. (I have a 1973 Firebird Esprit fitted with the rally pack guages as standard - i.e the volt guage and a fuel guage.)

Reason for the question is I have a problem with the alternator. The volts are pulsing and making it idle badly. It always did this but it got worse recently. I tried replacing the regulator in the alternator (S10) , that worked great for 50 miles and then the issue came back. Maybe I replace diodes next + regulator, maybe the whole alternator. In the UK you just do not have the places like in the US where you take and alternator for a health check - so I have to work it out for myself. Trouble is the wiring loom is a bit butchered and I am wondering if I am incorrectly wired and missing diodes or resistors or other bits and bobs. So until I have the wiring fully worked out I dont want to keep throwing bits and money at it. It looks OK so far, but I am trying to trace the ignition line to the alternator.

Cheers for any help – Dave

[MN6WS6]

Your volt gauge is your "battery" light. My 71 with standard gauges has a battery or alternator light (can't remember right now), but you have the better actual gauge.

In regards to your problem, I think I'd start by checking all your grounds. Grounds are the most common issue on any vehicle, especially older ones. Next, make sure your belt is tight, as a slipping belt will cause voltage surges regardless of how many parts you sling at it. Since you don't have anywhere to have it checked, and considering how relatively cheap alternators are, I'd put a new one on it and see if that fixes it after you've checked the above two items. You can get a cheap alternator for probably $30 or so US dollars here, but I don't know how cheap they are over there, and I wouldn't buy the cheapest thing you can get your hands on. If you plan on adding a big stereo system, I'd recommend having your current one rebuilt to higher output or possible buying a new, upgraded alternator. But if the car is going to stay stock, any decent aftermarket alternator would be fine.

[ukdave]

Thanks for that - that makes sense - I just needed to be sure. Now I can stop hunting the interior for a hidden light and wondering if that is causing an issue !!

Thanks for the recommendations - I 'll give those a look. I did some voltmeter tests and it looks like the alternator is grounded OK. But, you still could be right, I think I might run a seperate grounding wire for the alternator to a chassis and the main earth point - I have seen that suggested elsewhere. Good news is the S10 alternator parts are available over here so after some checks I can do some rebuilding. Worse case I can import an alternator (it will b easier than putting some naff European lump on and having to fabricate brackets anyway).

Thanks again and happy cruising in your '71 !!

[MN6WS6]

I wouldn't limit my ground search to just the alternator. You need to check the battery to body, battery to engine, and engine to body grounds as well. All of those should be at (preferably) 4 gauge.