As you said, the Hurleys were the hot ticket back when my 20B was
built. During the past several years I have seen many of them fail
(mostly in turbo engines in cars) and done some informal tests on them (take
seal between thumb and forefingers and snap them fairly easily). I simply
lost confidence in them. To be fair, they will probably work fine in
normally aspirated engines where the rotor grooves are in good shape, especially
since you are using 3 mm seals which should be stronger.
The other factor is the 'company motto' for RWS which reads "We Fly what we
Build", so since we now make apex seals I was virtually obligated to do
it.
Tracy
----- Original Message -----
Sent: Wednesday, July 26, 2006 10:42
AM
Subject: [FlyRotary] Re: 20B back
together
Tracy,
Can you expound on
the need to replace the Hurley seals. I have the 3mm Hurley seals in my
20B, with about 10 hours of ground running. At the time I was rebuilding
my engine Hurley seals were the best seals to use, or so I was told. So,
what’s changed? I also have the TES o-rings installed throughout.
Thanks,
Mark
S.
From: Rotary
motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Tracy Crook
Sent: Wednesday, July 26, 2006 9:00
AM
To: Rotary motors in
aircraft
Subject: [FlyRotary]
Re: 20B back together
The tear down and
apex seal replacement job on my 20B turned out to be a 6 day ordeal
instead of a quick 2 hour job but it's done and I can get back to
finishing the RV-8 again. Most of the problems were caused by
inexperience (haven't had to tear down a rotary in over 12
years) and the fact that this was not a standard 20B but a mongrel built
out of mostly 13B parts. I went ahead and replaced the
stock coolant O-rings with TES parts while replacing
the Hurley apex seals.
Tracy (packing
old GPS in plane for
backup)