Identifying a voltage regulator

[uranian]

I think that my voltage regulator is the source of my troubles with battery recharging, so I'm trying to buy a replacement. However, the regulator has no part numbers, brand or any mark of any kind on it, so I've been hunting the EPC for the part number. That states that the replacement part number is A 002 154 58 06, which in turn is listed here as having a Hella 5DR 004 241-151 regulator as a possible replacement for the original MB part. However, here, that particular Hella regulator is listed as having a 32mm diameter, while the regulator I took off the vehicle has a 28mm diamater.

So I'm stuck...I don't want to buy the wrong regulator and fry my battery, but I have no idea what the original regulator is. Anyone have any suggestions on how to identify the old regulator? Some pics:







Engine originally (this is in a 1969 L406DG) was an OM615.910...not sure whether it's the original engine, as I can find no engine number on it (couple of places on the engine where it looks like a small plate was riveted to it, as they used to do for engine numbers, I believe), but the identifying plates are long gone. I am of the opinion that it's probably not the original engine, as there's no power steering (which was on the 615.910, according to the EPC), and the oil cap is a different shape (I've been reduced to this kind of identification!), and it's done less than 200,000km, which for a 40 year old engine seems remarkably little.

I can buy a 28mm replacement by Hella, and hope it works...but I don't want to turn the battery into an explosive device...thus hoping that someone here might have some helpful suggestions.

TIA

[vox_incognita]

Well,according to the bosch online catalog,the L406DG with 615.910(2,2l, 60HP) came with external regulator,so there may have been some upgrades on your engine(if it`s the original one). This regulator on the photos look like ,ahem, a white box one...the alternators of w115,w123 (om615,616,617) all seem to have used the 32mm regulator(after 1975)...i think both will fit.
Anyway,have a look:
http://www.bosch-automotive.com/ecat-online/
www.autoteile-shopping.de
http://www.dieselgiant.com/mercedesvoltageregulatorinstall.htm (this one is for 55A altern)

[thesst]

Those pictures could be modern art.

[MattBelliveau]

Originally Posted by thesst

Those pictures could be modern art.

Agreed. Is that thing sitting on a roof or something? I agree with vox. Looks identical to the one that came out of my w123.

[vstech]

I kinda doubt that any roof would be mortared brick... a wall more likely
I would like a better view of the surroundings in those photos, adobe building in background and rough brick in fore...

[uranian]

Glad the pictures were enjoyed. The PITA (to ID) regulator is sitting on my (roof) balcony in sunny Andalucia, Spain.

I contacted Bosch about this and they sent a helpful document identifying all the Bosch electrical parts that came with my van originally. That stated the regulator was external, which it clearly isn't, which is more pointing in the directon that the engine isn't the original.

Is it safe to assume that if I get a regulator with a 28mm diameter, it'll work as the old one? I'm not convinced of that, but then my electronics knowledge is minimal.

EDIT: think I read somewhere that if the brushes are of a different length, that's a problem...is that right?

[t walgamuth]

Where in Andalucia?

Tom W

[uranian]

Granada.

[kerry]

Originally Posted by t walgamuth

Where in Andalucia?

Tom W

The former Muslim part of Spain, in the south.

[uranian]

still not identifying the reg, but here's another nice pic of the locale:

[vstech]

I would think uneven wear is a bad thing. maybe you can pull the alternator and post a pic of it along with the better pics of the surroundings. or post the model # of the alternator. and you could order a new or factory rebuilt bosch unit.

[vstech]

... nice house. how many rooms? I am sure I could park all my cars there...

[SD Blue]

As long as the regulator is 12V and fits your alternator, it should not be a problem. In order for an alternator to put out a significant increase in amperage, there must be changes in the rotor windings. This is a voltage regulator and as long as the new one is not 6V or 24V the only key thing is fit. I'm betting Bosch should be pretty standard on dimensions in that respect.

[barry123400]

They have at least two variations in slip ring diameter for their regulators. You fellows are aware slip ring replacement is possible as well? Not for size but to deal with excess wear. They are cheap as well. Basically I ignore the individual given specs and just put what new one I have on hand in. As long as the diameter requirement is met.
Have not had any trouble with this approach over the years on bosh volkswagon alternators. Mercedes are very simular.
One problem is the cost. There is a tremendous spread on pricing for regulators. I think the bosh unit is the best but some of my aftermarket ones cost about three dollars and have stood up well.
I see no way you are going to damage your battery. Basically they all function about the same. Call an alternator repair shop and price a regulator there. You can also address your general questions to them.

[uranian]

Barry and Blue: thankyou!