hi skip, (and members)
wow.
so not only are there two different seal types used to match the different
shapes of the shuttle, but you are saying there is another factor with the
switch in the middle at the cross section?
GREAT! :-(
the reason i ask is because i am trying to find a shuttle for you my friend.
:-)
I have dug up a PDWA and need to take it apart.
but i am having trouble extracting the shuttle though to make an inspection
for you.
any insights/advice?
do you still need a good shuttle?
james
>From: Skip Montanaro <skip@pobox.com>
>Reply-To: skip@pobox.com
>To: "James Tabor" <jattr6@hotmail.com>
>CC: 6pack@autox.team.net
>Subject: Re: Late style PDWA shuttle needed: question
>Date: Sat, 15 Jun 2002 00:43:51 -0500
>
>
> James> Skip referenced the need for a late style, but then calls the
>cup
> James> design the late style... the LATE model shuttle i believe is
>in
> James> fact the one that skip has. (the one show on the top in the
> James> photo referenced below). So did skip mean to say he needs an
> James> EARLY shuttle?
>
>James,
>
>I think I just worded things badly. The picture I referenced shows two
>shuttles, an early version with cup seals, and a later version with
>o-rings.
>Not knowing any better, I assumed there were only two styles of shuttles.
>I
>bought a PDWA from (purportedly) a '72 or '73. The text from Nelson's MC
>rebuild article on the Buckeye Triumphs site says, in part:
>
> I have PDWAs from years '68,'70, '73 & '76 and all have 5/16"
> cylinders. Three use O-Ring seals as the lower piston in the
> photo and one uses the more substantial seal as the upper piston
> in the photo.
>
>Knowing that I had a '68 PDWA with cup seals, I assumed that at least from
>'70 onwards o-ring style shuttles were used. I incorrectly assumed the one
>I was buying would have an o-ring shuttle. It had a cup seal shuttle, but
>it was slightly different in cross section in the center switch activation
>region than the shuttle from my TR-250. I then inferred (perhaps also
>incorrectly) that what I purchased was what I think of as a "late" cup seal
>PDWA.
>
>It's not obvious to me that you couldn't use o-rings on the cup seal style
>shuttle, but you'd have to find o-rings with much smaller inside diameters
>than the TRF rebuild kit provides. The pressure bears from the ends of the
>shuttle which would tend to press the o-rings up against the inner
>shoulder.
>You might have to place two o-rings on each side. Has anyone tried this
>successfully?
>
>Moral of the story: Don't buy a pig in a poke like I did. Check the
>shuttle
>before buying...
>
>Skip
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