Date:         Sat, 7 Jul 2001 00:32:31 EDT
Reply-To:     FrankGRUN@AOL.COM
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Frank Grunthaner <FrankGRUN@AOL.COM>
Subject:      A new Adventure on the way to the Audi 2.0 Turbo - or pulling
              gears
Content-Type: text/plain; charset="US-ASCII"

I have had a new adventure (on the scale of my varied stimulations) and found
an intriguing solution to a very difficult PIA problem, as I work my way
through the hardware manipulations required to complete the Audi 2.0 Turbo
project.

The problem: I'm switching to an all Saab/Bosch engine management system for
engine and turbo control. This means LH-Jetronic ECU and fuel injection and
the Saab APC knock-based control of turbocharger boost pressure and Saab
ignition. As part of the Saab approach to detonation control, they use a
distributor with Vacuum advance and retard, and no centrifugal advance. The
Audi 3A engines (despite the erroneous notation on the EKTA) use a
non-advancing distributor (knock sensor controlled ignition as per the CIS-E,
Digifant and Motronic engines). I therefore wanted to make a Vacuum
advance/retard only distributor compatible with the 3A engine. This Audi
distributor uses a very large engaging gear (about 1/3 larger diameter than
the regular VW counterpart) and a larger entry port for inserting the
distributor into the engine. The VW CIS distributors have the necessary Hall
ignition, but include both centrifugal and vacuum advance and a too small
gear. The obvious solution, swap gears between the Audi and VW distributors!
The manuals say: "Drift out (whack with a hammer and punch) the locking
cross-pin and remove the gear from the shaft" Well it wouldn't come off!

I whacked and I whacked. I went through (means badly mangled) four Craftsman
pin and center punches (love that guarantee - had to get the wife to exchange
the second set) and still my sweaty reflection could be seen in the unmoving
surface of the drift pin. After several shaking defeats (evidenced by the
painfully swelling discolorations of too many of my smaller appendages) I
took stock of the situation and went off in search of a machinist with the
proper tools, level of experience and fully functioning digital subsets.
Well, four of Pasadena's finest looked at them and said "those are like VW
parts" and sent me on my way. One confident wizened fellow announced he
couldn't get to it then, but they would be ready by noon the next day. Later
I noted that his pinkie was absent on the right hand. Well, the next day soon
became 7 days later with 5 successive one day excuses. On the seventh day, he
announced (for the PC conscious please note I'm only reporting here) "Those
pins are a real bitch. I've heated and cooled the shaft ... etc". You know,
excuses. Then he said, "So I've sent them to a VW machinist (!!!) and they
will be back tomorrow!" On the day after the morrow, he said "He just sent
them on to a VW machinist (!!!) who specializes in distributors, they will be
back tomorrow!" Then the exciting breaking story, "He has one of them out!,
they will be ready tomorrow!"

Well to truncate this report, yesterday, he asked me to come and get these
G...DD...M things the H..  out of here (trying to keep this clean). I picked
them up, and clearly progress had been made ... the surface of the end of one
of the pins was marred.

I then called Tectonics who had said, "just pound 'em out!" who now said,
"Well I'd drill them out. Start at 1/8 inch bit then slowly work your way up
to 5/32 then punch 'em out". He went on to observe that the pins were tool
steel, and I should get a handful of high quality bits and prepare for a
weekend worth of drilling.

I recounted my tale of woe to one of my trusty JPL machinists (with some
minor embellishment) in a blatant attempt to solicit his professional
assistance. Whereupon he said, "I'd plasma arc the damn thing!"

The solution: Well he sent me off to a little shop in an industrial
park/getto in Irwindale. I showed the fellow my pieces. He asked a set of
surprisingly well informed questions about the metallurgy and engineering of
the gear and shaft system (and how much money and time I had), and announced
he would give it a try, but for a litany of reasons there were no guarantees.
Today at noon he called and announced that they were out and that would be
$20 per pin please!

The wonder: What he did! He used a hollow electrode setup to strike a highly
confined Nitrogen arc to rapidly cut the metal away (similar to a plasma
torch). He calls it a metal disintegrator beam (!). He used a square
cross-section electrode to cut through the 4 mm pin along its 15 mm length.
Then pushed the remaining pin casing through! This thing cuts through
hardened tool steel like butter, but there are no burrs or even
discolorations on the inside of the gear or shaft hole. Amazing! Wow!

Oh, well as you can sense, I had a good time!.

His Name is Jim, his business is:

Bradley's Broken Tool Removal Service
5277 N. Vincent, #40
Irwindale, CA 91706
(626) 969-9565

Sorry for the length, hopes this helps someone else as much as it did me,

Frank Grunthaner