Voltage Regulator Replacement

[Demons1964]

I have a VS V8 showing all the classic symptoms of a voltage regulator on the way out. Warning light flickers periodically (i.e. total 15 seconds over the period of a 40 minute trip to work) and all terminals & connections appear tight. Alternator appears to be putting out sufficient voltage (except for when the regulator is playing up which is never when I'm testing it!!). I have bought a new Bosch regulator & brush assembly and I was wondering if it is necessary to completely remove the alternator to replace the regulator? Or can the regulator be removed and replaced without removing the alternator? I found one old thread on this forum with tips from Guy and Garth about removing the alternator and placing the alternator on its pulley to stop the commutator(?) moving. But I don't know if that was a V6 that had to have the alternator removed (maybe clearance problems near the regulator?) Haynes manual (piece of crap) is no help as it only refers to it in the overhaul procedure with the alternator already removed. Any advice and tips would be much appreciated.

Mark.

 

[DJ Majah]

The only help I can give you is with the V6, but it shouldnt be too different...or maybe not.

Anyway, the voltage regulator is on the engine side of the V6 alternator, so you have to take off the drive belt, undo the bolt at the top and the one under it on the engine side, then the alternator will swing up away from the engine. You can leave it there if you want, cause you can see the V.R. with two little tiny screws holding it in. Take them out then you can pop in your new one.

 

[markovr]

if the voltage is within limits 13.5-14.5 with the engine running it probably isn't the regulator itself but the brushes worn out and loosing contact with the slip rings on the rotor. They are under spring pressure but as they wear down the copper pigtails that they are connected by get to their max travel and stop the brush from coming out any further and making a good contact.
If you take the regulator out it contains the 2 brushes in question...check their length and if they don't seem to come out far then thats your problem and you can get them separate and solder new ones in.
If it is needing brushes the alt light will come on more frequently as time goes by and then finally stay on.

 

[Smitty]

I have a VS V8 showing all the classic symptoms of a voltage regulator on the way out. Warning light flickers periodically (i.e. total 15 seconds over the period of a 40 minute trip to work) and all terminals & connections appear tight. Alternator appears to be putting out sufficient voltage (except for when the regulator is playing up which is never when I'm testing it!!). I have bought a new Bosch regulator & brush assembly and I was wondering if it is necessary to completely remove the alternator to replace the regulator? Or can the regulator be removed and replaced without removing the alternator? I found one old thread on this forum with tips from Guy and Garth about removing the alternator and placing the alternator on its pulley to stop the commutator(?) moving. But I don't know if that was a V6 that had to have the alternator removed (maybe clearance problems near the regulator?) Haynes manual (piece of crap) is no help as it only refers to it in the overhaul procedure with the alternator already removed. Any advice and tips would be much appreciated.
Mark.

mate remove the alternator.....
it can be done in situ....if you have 3 elbows and 2 wrists
and a cupla unijointed screwdrivers.....
seriously..
it is a piece of cake on the bench...so remove the alternator
(undo bolt on adjuster and then remove bolt on pivot)
unscrew old reg..and remove
and put new one in and replace retaining screws....
just watch the brushes as you insert the reg assy
re-install alternator...
this is one easy home repair jobbie....
took me about 20 mins all up (inc r&r the alternator)
on my VR 5.0

oh
and disconnect the battery FIRST..before you do anything

cheers

 

[Tony2]

Changing the regulator with the alternator still on the car is easy. There are 2 screws holding it in and only takes a couple of minutes to do. If you already have the new one just put it in and if it dosnt solve the problem then investigate further. Mine was doing the exact same thing and was fixed after changing the regulator. On mine though the connector on the reg had been knocked and the casing was cracked so I dont know if that could have been the cause of the problem. With brushes, from my experience, they work fine but once they are worn to their limit the problem esculates quickly to the point where you have no charging at all.

 

[Demons1964]

Replaced the regulator on the weekend. Brushes were down to 7mm and the soldered contacts on the underside of the regulator looked dirty. No warning light on the way to work this morning so thanks all for advice.

Mark.