heat sinks and alt repair question, here's what I did

[rbraun at mail.enter.net]

OK, here's what I did, I used HSC on the bottom of the diode pack on 
all but the last 1/2 inch where the positive stud goes through, there 
I used Thomas and Bett's conductive grease (copper colored stuff), on 
the other end I drilled through copper plate and alt case with a #19 
drill and used a 8-32 x 1/2 screw w/ lockwasher and nut on the 
outside.  This way heat should conduct along with the over 100 amp 
current this thing can put out.

What I would like next time is one of the "iceberg" brand alt. they 
have a finned case right where the diodes are.  I'm just guessing 
that the resistance of the HSC adds to the heat in the diodes.

Resistance is not only futile, but also very bad (at least in 
electrical circuts)


> Again -- do not skip the heat sink compound.
> 

> > << The alt on my '91 GTA just puked, it's a CS-130 105 amp, I got it all 
> >  apart and the way I see it the diode package grounds to the case 
> >  through the heat sink compound.  I'm thinking the poor ground thus 
> >  created is adding to the heat of the diode pack and helping to 
> >  cause them to fail.   Should I leave heat sink compound off 
> >  entirely?, or at the end where the output term connects? or add a 
> >  ground wire?
> >  
> >  The base of the d-pack is 3/32" thick copper plate which mounts to 
> >  the alum case of the alt.  Would a copper to alum. mount 
> >  transfer electric and heat better with or without the heat sink goo?
> >  
> >  Any EE's want to give opinions?
>
> >   >>
> > Be sure to put plenty of heat sink compound back on the diode pack.
> > 
> > I'll bet that your alternator's back is blocked buy engine components
> > that is why the diode pack is overheating, no air flow!
Randy Braun     rbraun at enter.net
91  GTA
82 Firebird