I have an idiot light in my RPU for the charging system which works fine. I decided to go ahead and hook up the amp meter since it is already in my dash anyways. In case of a failure, I used a maxi fuse in between the starter solenoid and the amp gauge to keep the precious smoke inside. Then power comes out of the gauge and goes to my ignition switch to power everything else. With the key on, I'll pull the light switch and it shows a discharge so it is hooked up correctly. The problem is when it is running with the lights on, it still shows a discharge? When checked with a multi meter, I have 14.5 coming out of the generator so I know its still charging. What gives? I tried another gauge and it's showing the same thing. It's a flathead with a generator that I converted to 12v.
I'm thinking you have it hooked up so it is just feeding the accessories from the battery and there is no power going back to the battery though it because it isn't connected to the charging system. OR and that is a big OR, the way it is hooked up the charging system actually bypasses the ammeter though the original wiring. It's been at least 40 years since I hooked an ammeter up like that so I am a bit foggy on exactly how to hook it up right. This pfd from classic might help some https://www.classicinstruments.com/userfiles/files/Manuals/Amp Gauge Installation 012313.pdf
Does it show a charge with the lights off? Or right after you start it? Keep in mind that ammeters measure amps, and generators can show adequate voltage even if the load exceeds the output which would show as a discharge on the ammeter. So discount the voltage reading... I'd try wiring one of the ammeters in series with the charging system output wire that goes to the solenoid, leaving the dash-mounted one connected. If you get the same results on both, it's likely your generator needs to be rebuilt or the connected load is more than the generator can deliver.
Does the solenoid have only one wire beside the cable going to the battery on that post? If so, the ammeter needs to go between the cut in the wire.
Yes, I spliced into the only hot wire coming off the solenoid. It's looking like I have a bad connection or something. I just went on a couple hour ride, half in the dark with my lights on. When I shut it off it wouldn't start again. Battery is dead. Got a jump and got home. With the multi meter I'm getting 14.5 coming off the post on the generator. But checking anywhere else in the system, I'm only getting 11 or so. The charge isn't making it back to battery. So I'm chasing wires and checking connections while the battery is on the charger. This battery is only a week old so I know it's good
Don't you need to POLARIZE the Generator nd Regulator to tell it the correct direction to send the charge?
Your meter shows 14.5 at the generator but what does it show at the battery? If low you need to trace it at every point starting with the regulator and find where the voltage drop happens.
Am I missing a wire altogether? I thought I had it wired up correctly. Sounds like there is supposed to be a wire coming off the generator ARM going to the A terminal on the regulator, then another wire (which I don't have) connecting the A terminal back to the Ammeter?
Alright, did a bunch of tests. At the "A" terminal on the regulator I'm getting 14.5 volts but on the "B" I'm only getting 13. Seems like the regulator is not letting the full voltage through? I went ahead and ordered another regulator even though this one is only 6 months old. I'll throw it in tomorrow and see what happens. Any other ideas?
Fixed! New regulator did the trick. This old one looks fine inside but I'll have to mess with it to see if it can be repaired to use as a spare
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