So i replaced my voltage regulator in my alt.
now the alt light comes on bright sometimes when im driving.
it seems to only happen at slower speeds.
is my alternator giving up the ghost?

1982 300d

What was it doing before your replaced the Voltage Regulator?

No or low charging issues seem to revolve around loose Belts, Voltage Regulator/Brushes, Wiring problems (sometimes the Connecor at the Alternator is corroded or sometimes the Alternator is not well grounded) or a bad Diode/s in the Alternator.
Once in a while a bad Batter mimics something wrong with the Alternator.

Removing the Alternator and having a free test done eliminates the a Wiring issue and depending on how updated there Alternator Tester is they can tell of a Diode/s is/are bad.

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84 300D, 82 Volvo 244Gl Diesel

i put n a new regulator because when i was driving before ..the light would come on dimly..now its bright
brandy new battery

You did not mention checking the Belt adjustment.

Inside of the hole where the Voltage Regulator goes there is a metal Finger that has to make contact with the Voltage Regulator.
Over on another forum someone had an Alternator where that finger was corroded.
Also one part of the Voltage Regulator on one of the screw holes needs to make good contact with the Alternator Housing. Shiny bare metal on the Housing would be best.

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84 300D, 82 Volvo 244Gl Diesel

It is possible that you did not install the voltage regulator correctly or it is a faulty one. I had the same problem with the 190D, a very dim alternator/battery light only visible at night. I changed out the voltage regulator and problem fixed. I found the carbon brushes were short and badly worn.

Questions:

1) Did you see any differences with the length of the carbon brushes between the old and new one. The new one should be quite long and springy.
2) Did you slightly clean or sand down the armature of the alternator with the VR removed? It helps to seat the brushes better.
3) You changed it with a new or known good one?

It is very unlikely to be a loose belt if the light is 'bright'. It needs to be slipping real bad to come on.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

changed with brand new vr.
bosch
did it with in the car
one of the screws completly fell apart.
so i replaced both with hex heads instead of the slotted screws
new belt also
i might just get anew alt for peice of mind

new belt...

Chances are when you installed it...you didn't tension it correctly or it stretched a bit...

Do you have the single belt alternator or the two belt one?

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ill crank the tensioner a bit. more..i replaced that also
this car was so work on so half-assed..no im going around and fixing all the stuff the PO did. but the good news is i got it with a 150k on it. and drives like a dream...just some little poop im taking care of


thanx for the responses guys
still learning

soon as the weather warms up
1. valve adjustments
2. transmission gasket and filter
3. manifold gasket
4. new timing chain...do not know the history of the one in there

and maybe rebuild the vaccum pump

i plan on keeping mathilda for a while