Joe,
Thanks for the reply and comments. I understand you POV but I suspect
that you are a digest subscriber, as I am, and haven't read my latest
follow-up.
Last evening, I posted a follow-up on the topic and related some
information which I'd uncovered yesterday. I won't know for sure about
my ;articular case until I remove the PWDA (this weekend's job) but the
chemist I talked to at PSP believed that I was sold the wrong
composition o-ring in the first place. The fact that the shuttle now
moves very easily is a completely different situation than what I first
experienced upon PDWA reassembly and recentering the shuttle after
refilling and bleeding the system. At that time, it somewhat resisted
movement. The chemist I contact believes that I might find
disintegrated o-rings upon disassembly, hence the ease of movement and
the leak, and thus confirming the installation of the wrong material.
WRT the size issue, there isn't a lot of choice for this ring. If you
check the PSP website, they list the dimensions of available o-rings and
there's not that much chance of an error wrt the correct part.
http://www.pspglobal.com/frameset.html
Cheers,
Gary
Joe Sholtes IV wrote:snip
> Gary,
>
> Since you did rebiuld the PDWA switch, with o-rings that you sized
> yourself, I think I have an idea what's wrong. You must have gotten
> o-rings that are not sealing properly. I think they are the wong
> outside
> diameter or the wrong thickness (which will affect O.D. if you
> measured
> the size by the inside diameter).
> I don't think silicon brake fluid makes a difference.
We don't want to start this thread up again but I agree with you here.
> The big deal with
> DOT 5 not sealing was that when it was first introduced, it caused
> problems
> that have since been solved. From what I understand, brake rubber
> seals
> are made undersize, anticipating the swell from DOT3 fluid in the
> system.
> When DOT 5 first came out, seals failed due to lack of this swelling,
> but
> additives have since been added that swell all rubber parts the same
> amount
> as DOT 3. The worry over DOT 5 being bad for brake seals is as
> obsolete as
> worrying about putting a battery on bare concrete..."It'll make the
> battery go
> flat in no time, you know..." I don't remember where I read this, but
> I think
> the info was related to this list somehow.
> The PDWA block was leaking out the electical plug area, because
> that's
> where they leak when the o-rings fail.
> And lastly, the fact that the shuttle is moving very easily further
> confirms
> my suspicion that the o-ring aren't sealing properly, since there
> should at
> least be some drag on the inside of the cylinder.
>
> All of this is assuming you haven't monkeyed around with the bore of
> the
> PDWA block, which would open up a whole new set of possible problems.
No problem here either; I used pipe cleaners.
> JOE IV
> TR 250
> WALLINGFORD, CT. USA
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