ammeter reading on 69FJ40

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I have a 1969FJ40. New battery, new alternator, (new volt regulator which I haven't installed yet). I don't have very good connections between my fuses and the copper clips they snap into. I'm always having to press on a couple to get my blinker to come on or to get my heater fan to turn on. I even added a drop of solder onto the clips in hopes to get a better connection with the copper rivet that connects the clip to the screw/ wire holder. Any, that's just some background info. My question is how do I read an ammeter? On my guage cluster is an ammeter (amp - meter). On the left is -30 and on teh right is 30+. Most of the time when I am driving the needle is just a little to the right past center. But, when I turn on my blinker the needle bounces way down and back up keeping tempo with the blinker. Does that indicate a short? Does a well running vehicle with good wiring hold the ammeter needle on center whether you run accessories or not? Or, is the ammeter going to fluctuate with every draw on the electrical power? Someone care to elucidate.
 
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According to the description you gave your ammeter is doing just fine. It will show +amps when charging and it's normal for it to fluxuate a little with the signals on. To help with the fuse/connection issue I suggest pulling the fuses and using a round (rat tail) file to clean the clips. Be sure the battery is disconnected when using the file.
 
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Mine pretty much stays in the center when the engine is idleing or driving down the road. However, when I turn on the blinker, it pulsates to +30. When I turn on the headlights, blinker, driving lights and step on the brake, the ammeter gets pegged out past +30. I have a 350 installed and can't figure out the problem. I don't think it should variate that much. But who know, I've been wrong in the past
 
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[quote author=IDave link=board=1;threadid=8977;start=msg77916#msg77916 date=1071861222]
:slap: reverse the polarity!
[/quote]

I feel stupid... Where?
 
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I think what he's trying to tell you KJmeyer, is that when you are drawing that much electrical load on the system, your ammeter shouldn't be reading in the positive. It should drop below the zero (center) mark when you turn on all those lights.
 
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It isn't normal to dive deep into the negative. Even my old '54 chev with a generator and primitive regulator maintains positive current with everything turned on. It's probably normal for your stock FJ alternator and external regulator setup to bounce a little with the blinkers, but not more than an amp or so. My VJ40 (nice acronym Gumby!) with GM alternator stays just positive with almost no fluctuations, regardless of what is turned on.
 
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Weeeeelllll, mine certainly bounces with the blinker. Not 15 amps but maybe 10-7. New ammeter, new switch, new signal lights. So, what would cause such a draw? Nothing else seems to. It does have an afterPO flasher wired in....hmmm....
 

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mine does the same thing but it drains the battery after about two weeks a driving. i am thinking about replacing the alt and ext regulator with a gm with built in regulator. has any one done this and how does it wire in?
 
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You might just replace the alternator brushes, unless you are bent on replacing it. (I have not had any battery draining issues, at least since I did the brushes).
 
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My ammeter reads dead center alll the time. (While driving or parked without key turned.) Don't know if that's normal or useful info Travis.

-Bobby the Moose II
 
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When I first got the truck I obsessed about the ammeter. Thought I had a short that kept causing it to "bounce". Some guys told me that its normal because as an ammeter it measures "flow of energy" + or -. Voltmeter, on most newer cars only shows the charge on the battery, which should be fairly constant and not affected by turning things on and off (given the alternater is ok).

I stopped worrying about it and it has probably saved me a lot of trouble since I didn't start messing around with my electrical. Got a bigger, better Optima that helped some but I still bounce:)
 
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Large bounces on the ammeter SEEM to be the norm, from what I have read. I certainly have stopped worring about it, since I haven't had any problems in almost 2 years.
 
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Yeah, I agree a lot of ammeters do the bump which makes it seem like the norm. But I don't think the norm is normal. (Had a friend we called normal Norm in high school. Weegie wouldn't you know and he was FAR from normal. :D) Not sure but 7-10 amp fluctuations seem like a lot for a couple of light bulbs. That's 30% of the entire charging capacity of a 30 amp alternator just to tell someone you're thinking about turning? Seems high. What am I missing? ???
 
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Theo-I don't believe that the flasher bulbs are actually drawing 7-10 amps, it is more the swing of the ammeter.
Its like this-when you turn on your lights, or hit the brakes, watch the ammeter, it will swing hard to left and then stablize at a low amp draw. With the constant flashing of the flashers, there is no chance for the ammeter to stabilize, it is always swinging. If, for instance something was wrong and it did stick with one light on, I'm sure you'd find that it would show a small draw.

New alternator brushes and a new voltage reg help quite a bit with ammeter flucuations. Check the grounding of your flashers as well, that can have a large impact on how easily they flash.
 
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So you're saying the needle is thrown too far by momentum so that it appears to be drawing more than it actually is??

Lookie here pup! I'uz wachin' ammitrs bounce afore ye was bornd and i kin shore tell ye a thing ur too if I'uz a mind . . . [old fart rockin' on the porch, scratchin' his privates and peering into the horizon]

Seriously though, I have the same behavior you're describing (turn on the lights and see the needle shoot down then stabilize at low positive). But the only time the needle wanders beyond about 1 or 2 amps from zero is right after I start it or run the winch, which is normal because those truly are deep draws on the battery and it takes a minute to recover. Believe me I've seen the deep diving ammeter on plenty of rides. But I still don't believe it's normal.

I hear you about grounding. My old truck has "recurring bad ground syndrome". Fix one and another crops up. Can't hardly keep ahead of 'em. :D
 

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