[Vwdiesel] Opening Alternator Case

[Val Christian]

Milt,

Your friends are heat, and mechanical shock.  Both are bad for altenators.

For heat, I would use jeweler's tips on my oxyacetylene torch, focused on
the unheaded end of the screw.  The case will conduct heat away quickly, 
so the game is to apply heat intensely very locally, and then allow that 
heat to dissipate (which it will rapidly do).  Don't have a torch with 
jeweler's tips?  I didn't think so, but it's my first approach.

The next approach is mechanical.  Impact is of little use on the 4 inch
screws, because they have allot of torsional elesticity.  So a conventional
"mouse" or other impact tool will only serve to get the head loose,
not the threads, which are your problem.  In this type of situation, I
support the altenator, so that the screw end area is held on a block 
of wood, and I use a hand held "swing and hit it" type of cam impact tool.
I have an old one from Sears, that came with Phillips heads.  Other places
sell them, as well.  Not as popular in recent years due to the proliferation
of air impact tools.

Barring these approaches, I'd get the altenator where it's warm, and 
tap on it daily, giving it a light penetrant at the problem area.  
If you don't have the jeweler's torch, you may have a regular propane 
torch, and you can gently heat the screw area to 150F or so, and then
apply the penetrant.  It will help it spread in.  I've taken the "do a
little bit every day" approach to taking these kinds of things apart, 
and had pretty good success.

If you're not so patient, cutting the screws, and then drilling and retapping
is the alternative.

Good luck, and let us know how you make out.  BTW, I've found that the 90A
altenators will put out close to 120 amps at RPM.  Did you get a good 
source for the bearings?

Val





> 
> Since I put in the adjustable regulator I wanted to open the case of the used 90 Amp unit to renew the diodes as well. Uses the 4 inch long 5mm screws with Philips heads. Well its the usual story; can't get the screws loose even after oil penetrant. Tried the double nut trick on the ends and turning, but no luck. Just stripped some threads. Also tried a Vice Grip in the open center centers, still no luck. I could try sawing off the screws in the open center, which might relieve some pressure and then using a Vice Grip on the screw ends.  Anyone remove these annoying screws? Milton. 
> 
> Send instant messages to your online friends http://uk.messenger.yahoo.com 
> _______________________________________________
> Vwdiesel mailing list
> Vwdiesel at vwfans.com
> http://www.audifans.com/mailman/listinfo/vwdiesel
>