Date: Sat, 13 Jul 2002 17:22:54 +0100
Reply-To: Clive Smith <clive.harman-smith@NTLWORLD.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Clive Smith <clive.harman-smith@NTLWORLD.COM>
Subject: Re: Disc seizures - chromate compound
Content-Type: text/plain; charset="iso-8859-1"
I think when you say ant-seize (compound) there might be many types and
makes of this.
To avoid this type of corrosion seizure, particularly between dissimilar
metals - the aircraft industry uses something called chromate compound, its
a yellow paste and I beleive it contains zinc (maybe zinc chromate then)
One name I remember was JC%A joitning compound, I bet that'll slow it up a
bit, but then I don't know ehere to get it from now .
Clive Smith
'88 Syncro Transporter
----- Original Message -----
From: "Richie Chunda" <Richiesbad@AOL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, July 12, 2002 7:01 AM
Subject: Re: No Subject
> In a message dated 7/11/02 11:40:21 PM, jcessence@HOTMAIL.COM writes:
>
> << I am trying to remove the rotors on my 87 syncro... ... Does anyone
have
> any ideas? >>
>
> John,
>
> I have been through the misery which is now staring you in the face more
than
> once. First, I will tell you what I found to be the source of the
problem:
> there is far too little clearance between the OD of the hub flange and the
ID
> of rotor. I would guess this gap is about .030". Whenever the ID of the
> rotor rusts, the exfoliating iron oxide fills this scant space solid and
the
> rusty rotor becomes one with the universe and, unfortunately, also the
hub.
>
> The first time I was confronted with this problem, I saturated the rotor
with
> penetrating oil, applied some heat and went at it with a 2 lb. copper
hammer.
> After some abuse, it came off. At the time, I did not realize that I
was,
> in some small way, lucky. More about that later. I saw what the problem
was
> and as I mounted the shiny new Brembo's I thought for sure by painting the
> mating surfaces with anti-seize that I would not get stung again.
>
> When it came time to renew the front wheel bearings, the anti-seize
slathered
> Brembo rotors would not even budge. In the end, I removed the rotors with
> the hubs still attached. The rusting was much worse than before. I
descaled
> the rotor/hub joint as much as possible with every kind of pointed tool
> imaginable, then I soaked the assembly with penetrant and tried to press
them
> apart on my small press. At the point that it appeared something might go
> bong and drop my sorry ass into a carefully dug hole in the ground, I
decided
> to try a different approach. I placed a piece of plywood on the floor
with
> the rotor/hub (inboard side down) on it supported by a few blocks of
> hardwood. I then heated the collar of the rotor with a rosebud tip in an
> oxyacetylene torch. I wanted to heat the rotor as quickly as possible so
> that little heat would soak into the hub. As soon as I thought it was hot
> enough, I held a 6" length of 2" AL round on the center of the hub and
gave
> it one hell-of-a smack with a heavy hammer. It finally popped out. In
> hindsight, I should have wasted away the rotors on the lathe; it would
have
> been quicker.
>
> Before, I mentioned that I was lucky the first time. I was lucky because
the
> original rotors were OE and they rusted far less than the Brembo's. When
I
> unpacked the Brembo's, I was duly impressed with the machine work on them.
> What I could not see was the metallurgy in them. As pretty as they were,
I
> have never seen rotors rust to that extent. So, if you have aftermarket
> rotors, you might have to cut them off. Keep in mind, that the edge of
the
> hub flange is almost hard against the ID of the rotor.
>
> I have heard some guys talk about beating on the rotors until they break
> apart. Given a big enough hammer, I guess anything is possible, but it
will
> also ruin your wheel bearings while you are pounding away at it.
>
> Although Syncro OE wheel bearing last a long, long time, if you think
yours
> will need renewed soon, now might be soon enough.
>
> Richie
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