Anybody here opened up an alternator?

[English]

Recently had a flat battery on the truck. Took it out to charge it up on the trickle charger, and when I topped up with de-ionized water the battery took A WHOLE LITRE to top up.

Once the battery had charged I drove to my local garage for them to put their battery tester on it. Battery tested out okay. They suggested that if the alternator was playing up it might have boiled the battery. Sounds reasonable. I hadn't worried about my voltage gauge reading on the high side (but not in the red) as 1) I doubt it was accurate when it was new, and 2) it was new 37 years ago.

I want to change the regulator, but I see that the regulator is internal on this vehicle. I've only changed external regulators before. The Chilton manual doesn't say how to change an internal regulator. Has anyone here done one? Is it easy to take apart? Do I need heat paste or anything like that?

[hatzie]

The 10SI and 12SI alternators are nowhere near as easy to service as the CS130D and AD237 in my more modern vehicles.  I personally would just get a reman.  They're cheap enough that it's not worth the trouble to split one of these open.

If you insist look in my signature for Service Training Group textbook link. 
The ones you want are GM_STG_1901_1_Delco_Truck_Charging_Systems (the SI series service starts on page 47) and GM_STG_16021_00_3_CHARGING_AND_STARTING

You'll have to carefully split the case open.  You should check the condition of the brushes, bearings and other internal parts.

Grab all three 1979 light truck manuals while you're at it.  The search function in a PDF reader will let you find the pages to open to in your paper manual.  I keep a stack of tiny Postit tabs on the computer desk to mark pages temporarily. 
You can also print out pages to take in the shop so you don't get greasy thumbprints on your 40 year old service manuals.  If they stay clean it may even be acceptable to SWMBO for you to read them indoors.
The 1973 Light Truck service manual has a lot of detailed component service information that's not in the later manuals too. 

[English]

If I need to carefully split the case open... I take it the alternator's not supposed to be user serviceable?
In which case I think I'll take it to a local alternator/starter magician I know, before ordering a new one.
Thanks for the tip

[hatzie]

If I need to carefully split the case open... I take it the alternator's not supposed to be user serviceable?
In which case I think I'll take it to a local alternator/starter magician I know, before ordering a new one.
Thanks for the tip

Not really user serviceable.  It can be done but it's a better idea to have a guru look it over.  They'll replace, lube, or adjust whatever else needs attention too.

[ehjorten]

Super easy to take an alternator apart and service it!  There are some tricks to it.  The biggest trick is using a small pin or hex key to pin the brushes back when you put the alternator back together.  There are other things you have to check also like short-circuit and open circuit of the rotor and stator.  If you haven't done it before and you don't have anyone to show you how, then it probably isn't worth it.  Remans are pretty darn inexpensive!

[English]

Dropped it off at the alternator shop last night, got a message this morning saying fixed and ready to go. New triode and regulator. £45 ($55). Can't complain!