generator light

took my 68 fleetwood 75 out for the first time for months and when I drove it back that night to the shop where I keep it stored the gen light was half glowing It might have been on when I took the car out but it was day light and I saw it when it was dark when I got to the shop turning off the head lights and rev up the motor did not help I have notice that the head lights flicker lighter and darker, I have had grandkids over sence parking it on friday and have not had a chance to check anything out yet, any ideas thanks
 
Check the connections at the battery, generator/alternator, and regulator to make sure that they are clean and tight. If that doesn't solve the problem, then it is in the charging circuit, and will require further investigation as to what the exact problem is. It is hard to diagnose electrical problems without a hands on approach..
 
Check the tension on the belt first. If its tight, and your idle speed is ok, then you probably have either bad brushes in the alternator or a regulator going bad. time to get a charging system check!
 
up any number of things. but do the easy checks first. as sugested.

if the brushes are in good shape then you could have loss tenishion on one of the springs. or the points could be pitted on the regualeter. seen it were one of the brushes gets stuck in the slid and is just making close enough contack to ark. but the big question is is the light bright red when the key is one and the engine off? if not the b rushes are not making contack. as the circet goes threw them.
was it at night? some time you get a bleed threw light with the dash lights that causes a glow. the check is to shut off the dash lights and see if it's still there.

simple system but the problem is usally brushes or a bad belt. the volt meter check will tell you if its charging.
 
I had a 69 that did the same thing, just a very dim glow. Everything checked out ok and never failed me, as ED said may be bleed threw from the dash lights. Dont take my word for it though, make sure you check everything.
 
new voltage regulator

so far I have done nothing, I bought a New regulator, the first one I bought I notice that it came from across the pacfic ocean and it cost $18.00, I went to NAPA and got one made local for $57.00 It is worth the extra cost. I will try the regulator first. The light is very dim with the engin is running and bright when the key is just turned on. but all belts are tight and I found no loose wires
 
you need to check it with the volt meter first before changing anything.you can do it right at the battery. it should read 12 volts when the car is off then when you start it it will come up to about 13.8. it should stay above 12 volts with everything on. if it does then the dime glow is either bleed or feedback. neather of whitch is a problem. taping the hole will stop the bleed and cleaning the ground will stop the feed back.
 
Both my 73 and 77 M-M's generator lights come on anytime the vehicles are running. During the day you really have to look hard at them both to see them but at night their noticeable. It seems as you speed up they get dimmer too. I've had both cars checked over, both generators and batteries are all checking out good. I've looked at the wiring diagrams and there is a resistor or a diode (cant recall with out looking) in the charging circuit according to the schematics that I think that may be bad causing the false reading from the generator dash light on my cars. I figure that sooner or later the bulb will blow and I really don't want to tear into the dash to take out one bulb ether!

So I just go ahead and roll with it.
 
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I would recommend finding and fixing the problem, even if the charging system is working. I drove my truck with a bad indicating system, and was eventualy left stranded in the middle of nowhere New Mexico. The alternator quit, and took out the battery. I never knew, because the indicating system didnt work.
 
Whats that??

the big boys would put a piece of tape over any hole they did not want to use in the instrument panel. or the back side has separated to were it will allow light to enter threw a crack. if it's near the hole for the indicator light it will let light bleed threw the red lens. if you rotate the dash lights off and the light goes out also it just a bleed threw giving you the glow. not the indicator light circuit. the light one bright with the key on is the test that the indicator circuit is complete and working.

also the light it's self works off a relay. as long as the relay is getting a charge to it it remains open. when it no longer receive the voltage signal it closes and the battery voltage lights up the light. if the points are bad in the relay they may not open up all the way and may give you a slight current. if the ground is bad for the relay it may not get enough voltage to open up all the way giving you a false indication.

now in Jeremy's case i would clean the connection to the relay put a star washer under the mount to get back a good ground then test it. if the light still flickers under load swap a new set of brushes and bearings in the alternator runs about 24 bucks .

I put a volt meter in the jeep if you want I can show you proper operation of a generator circuit using the voltmeter test. but one can use any of the multimeters out there at the battery to do the same test.
 
this is how the volt meter will test if you system is charging as it should. it will test the same if it's a generator or alternator. always test at a max load to see if the system can keep up . if its flickering back and forth you having trouble . [ame]http://www.youtube.com/watch?v=QfseY7-xdHQ[/ame]
[ame]http://www.youtube.com/watch?v=EQG67v389bQ[/ame]
 
Thanks

If I can get a spare night I will test this out. as I drive the head lights flicker I will try this at night with the gauge to see if it matches the flickering lights
 
If the lights are flickery, it might be a bad ground in the engine compartment. Most likely a bad ground wire from the battery to the engine, or from the chassis to the frame. I would clean every terminal that you can find first, before replacing parts. Flickering is a sign of a poor connection. Only after doing this, are you going to be getting a true and accurate reading. Many times the battery cables get corrosion under the insulation that causes a lot of these problems.
 
the test will come out the same in the daylight. but I know your not near the car at that time. always preform the output test with everything on that will draw. if it keeps up with the current draw and the lights still flicker you know its not the charging system that's at fault. however is the needle flickers along with the lights it's time to check connections before replacing components.
 
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