Hi guys, I have a 39-48 generator thats been converted to 12V with the proper field coils etc. Its mounted and grounded. Brand new Ford type 12v reg wired up correctly, grounded etc. Rebuilt 36 dist with the old coil removed and a 12V coil substituted. Paint has been ground away and the body is grounded to frame, frame to batt, engine to frame so the ground circuit is completed. Gennie has been polarised as well. So I fire it up and it shows around +2/+3 Amps at a fast idle. Turn the headlites on it jumps to +18A with low beams on and +20A with hi beams on??? Normally the Amps should be under "0" with low beams and even move under 0 with hi beams on, but instead its showing a truckload of charge with the low/hi beams on !! Did I screw up in the wiring ? Any thoughts ? Thanx
Yeah, I'm reading off the factory 32 Ford Amp gauge. I remember reading somewhere that the ammeter connections would need reversing when converting from 6 to 12V. Could this be the issue? Rat
I was going to say it sounds like you have something the wrong way around........but I know 5/10"s of fuck all with wiring. It had better make it to my place Sunday night.......no excuses
you need to reverse the wires on your amp meter thats all. As in swap them over to the opposite terminals.
Did that guys, will fire it up tomorrow to check it out. HF - Im bustin' my ass on this thing to get her rolling for Sunday, I think the carbs either have shit in them and need a cleanout or at least checking out.
You don't need to switch the amp gauge wiring because of the 6 to 12 volt conversion, you need to switch it because the car was originally positive ground and now it's negative ground.
I'd say that your regulator is not regulating correctly. The generator is working. The regulator is not keeping the output within specs. I don't know how to adjust a regulator. Is your battery fully charged? All my generators show a heavy charge after the car is started and then comes down as the battery is recharged. The regulator controls the out put. An ammeter is a flow gauge. It tells you which way the amperage is flowing and how much. Toward the battery when it's charging and out of the battery when it is not charging. That is the reason to reverse the wiring.
Guys batt is fully charged and in good shape. The reg is brand new (not that it means that much these days) and is the Ford style used from 1957 -1965. Its non adjustable from what I've been able to find out. Ive got the gist of the ammeter wiring and what its supposed to show, thanks. I'm gonna fire it up tomorrow, see what happens and post up the outcome. Thanx !
I personally don't trust modern reproduction parts. When I changed to a generator on my FE engine I found a NORS made long before the Chinese parts became the norm. I found mine on Ebay. Mine is an Atlas. I don't think that they are still in business. Brand new in the box sitting on a shelf somewhere for years. It was never recommended for harry homeowner to adjust the VR so we never learned how. It would void your warranty back then. Basically it's like adjusting your points but the setting was not widely available.
Someplace I have the directions for setting the points, it can be done with a volt meter. I used to have to do it all the time on a vehicle that I ran batteryless. I have an old echlin voltage regulater on my bench, the box is missing but it has never been used. Someday someone is going to need a good voltage regulator and I'll have one. That will make me pretty important.
I think your ammeter is doing exactly what it should, its recording all the amps being used. Turn on the lights, more amps used, more amps go through the gauge. You may want to use a volt meter to see how things really work in a charging system. Eliminate the ammeter, all the high current goes directly to the battery, the volt meter just tells you how the battery is. Safer that way.
If the ampmeter leads weren't reveresed and the generator isn't charging you would get numbers like you are seeing. Check it at the battery running with the lights on with a volt meter to see if it's less than 12v.
Good and correct point there. You did change to negative ground? Going by the specs for a six volt system doesn't fly when you start chainging and adding things. You want 14.2 Volts when it is charging with the engine speeded up a bit to be perfect. The generator won't put out optimum voltage at an idle. That is why on 90 % of cars running generators the lights go dim when you pull up to a stop light at night and then get brighter when you speed up and pull away from the light. It's almost like it's showing it's homies that it's running a generator rather than an alternator. As someone said previously an ammeter measures current flow both in which direction it is flowing and how much is flowing at the time. What headlights are you running. If they are halogen they will draw more amps than regular old bulbs. That would create a larger current flow I've got manuals and instructions for testing those and setting them at home but I probably won't be able to stop and sort though them for at least four hours. Someone else might come up with a solid set of instructions before that.
Its -ve ground and as in the OP, all the grounds are very good and the ground circuit is completed. Headlights are 12V std sealed beams, no halogen stuff here haha. Will fire it up in in the next day or two and see what I get after reversing the wires to the ammeter. Will also pop off the reg cover and see what it is doing at a fast idle. Rat
I don't agree with your theory that it should show 0 with low beams and discharge with high beams. Sounds to me like it is sensing total load on the system and charging the battery while also carrying the load of the lights and other accessories. I would run it that way a while and see if doesn't level off a little, just keep an eye on the battery and make sure you don't boil it.
I don't agree with your theory that it should show 0 with low beams and discharge with high beams. Sounds to me like it is sensing total load on the system and charging the battery while also carrying the load of the lights and other accessories. I would run it that way a while and see if doesn't level off a little, just keep an eye on the battery and make sure you don't boil it. Edit: also sounds like you have the polarity right, don't switch any wires if your needle is swinging to the plus side while running with a load on. Also just reread this whole thread and it dawned on me what the other were getting at. Try this, don't start the car just turn the lights on high, if the needle still goes positive of center then change the wires, if it goes to the other side you have them right.
I agree. The ammeter will show a small charge with the needle just to the C side of center. In the winter time with our northern heaters blowing full blast and the lights on it may fall to the discharge side at idle sitting at a light. My 57 Ford wagon would have the idiot light flicker at night and go out immediately when it was reved up. I got a new regulator and the light stayed off at idle. high beams should not cause the ammeter to show a discharge. Unless the battery is showing a charge with a volt meter and your amp meter is showing a discharge the direction of the wire is correct. All the ammeter does is show the direction of the flow and the amount of current that is passing through. If the direction is wrong just change the direction. IIRC the wire just passes through a loop on the back of a 32 ammeter and there is no physical connection.
Remember this is a custom wiring harness. It should show a discharge as soon as the key is switched on if it was a factory harness. A lot of modern streetrod harnesses don't run everything through the ammeter so it is not as accurate about diagnosing problems. I have developed a pattern over the years. I turn on the switch and check the ammeter if it moves the battery is probably OK and I start it up (I have a thing for starter buttons). After driving it I turn the Switch off and check ammeter. If it shows a discharge I know I left something on. It has saved me a dead battery more than once and discovered a bad brake light switch. When I got this truck the ammeter would not show a discharge only a charge. After a check, I saw that the wire feeding the fuse box as on the wrong terminal a quick change of the terminals and everything is the way it is supposed to be.
Amp meter should be between the battery and all loads except the starter or it will not be giveing correct readings.
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