On Thu, 17 Nov 2005 01:26:16 GMT, (jj)
wrote:

I'd like some opinions and reality checks on fixing an aluminum tranny
case (Dodge a604) that has one of the mounting "ears" completely
broken off and one partially. This is toward the back of the tranny
on the far end from the bellhousing. They both have a threaded hole.
Preheating the entire case to ~500F is not a problem and an AC TIG is
available. Sounds like 4047 filler is what most have used in the
past.

I am curious about how these would work out vs "classic" TIG repair:

1. Facing both ears and then brazing on chunks of aluminum and then
drilling/tapping?

2. Would getting a copper/bronze/brass bols of the correct size made
up and then placing it into the partially busted ear and building up
new aluminum be a good labor/time saving idea? Maybe some nickel-based
anti-seize on the bolt first?

3. How about the new hts2000 filler/ repair rods at
aluminumrepair.com. They claim some great stuff and google seems to
have some real and positive actual usage reports. The stuff is kind
of expensive though. ~ $70 for a 1lb starter pack. I'm figuring this
should be more than enough with a bit left over? This sounds
tempting as a "new thing" to try.

What did I leave out?

Classic TIG repair
1. Detergent wash the bejeezuse out of it.
2. Brake clean spray the areas being repaired.
3. Preheat to ~500F - maybe hit again with brake cleaner if stuff
bubbles up (away from open flame and not inhaling fumes)
4. Hit with clean brush and start laying down beads.
5. Slowly cool down, then grind to shape, drill and tap.
6. Maybe let it sit for a couple of weeks to reharden/temper.

Thanks!
Jay

I don't like the classic "miracle rod" like alumiweld et al. The
HTS2000 stuff looks interesting, testimonials are impressive. Note
that these alloys tend to be somewhat brittle. It might be OK for
some joint designs, but I'd expect joining a thick ear to a casting
might not work well. It won't "wick" into the joint like brazing
alloys do; you need full access to all surfaces so you can "scrub"
the rod on the workpiece to break up oxides. This necessarily
leaves a thick region of alloy because you'd have to V out the joint.

The site claims joints stronger than "heliarc" welds. I'd take that
with a large grain of salt. There may be special cases where that is
true, but I strongly doubt that it's true in general, or
particularly in the case of joining an ear to a casting.

I'd TIG it with 4043 filler. See
http://users.goldengate.net/~dforema..._mount_repair/
for an example of a somewhat similar repair. This repair has held up
well in service, with a fair amount of stress on the pin.

4047 might be better, don't know. 4043 worked well for me. 4047 is
a bit higher in silicon, has a slightly lower operating temperature.
I might try that next time.