> There has been a discussion on the nopistons forum about TES
o-rings. The installation
>
> method that some of the guys used may questionable, but I
thought
it may be good to discuss here.
>
> http://www.nopistons.com/forums/index.php?showtopic=67208
< http://www.nopistons.com/forums/index.php?showtopic=67208>
>
> Post 35 on the second page has some pictures of the o-rings
after
a tear down.
>
> What are your thoughts Paul?
>
> Heath
>
> I am not allowed to access that forum :) Obviously they
don't
want the truth :)
> If you want to cut and paste the message to an email and
send it
to me I will comment.
>
> If they are too big they WILL cause BIG problems. People
have to
> buy the exact right size directly from Creavey. What they
sell
elsewhere
> may not be the right size. For an example a 3/32" dia. O
ring
will not cut it and
> will cause problems as it is not .096" in diameter as one
would
think.
> It is .108" inches in diameter. TOO BIG!!!!!!!!!!!!!!!
>
> Here is a pdf file on the subject.
>
> Paul Lamar ...No rotor no motor.
You have to register and sign in to view the post. I PDF'd the
post
in case you
don't want to register. The post is concerning TES o-rings
Tracy
sells, and I
assume he followed your guidelines when putting the package
together. This may
very well be a case of operator error as far as proper
installation
as some people
that responded to the post had good luck and others did
not. One
person did reference
your website and write up on TES o-ring selection.
Heath Holbrook
I don't register and I don't require people to register here. I
ask
people here
to sign their name. Sometimes they don't but I know who they
are.
I don't know what register is about but I think they are just
gathering information
for marketing purposes.
No comment on the pdf as I don't know who "B" is :) He could be
working for
Mazda Parts Department :) The thing about the Internet is
there are
shills lurking
about. A shill is a person that is paid to discredit certain
products and services
and sell other products or services instead. I have certain
ways of
detecting shills
with about 12 years experience on BBS's and the Internet. If
I told
you about the
ways I would have to kill you :)
I will say "B" is not providing the required details on
diagnostics
of his alleged overheating.
For example; Does the water jacket hold pressure? Is there a
coolant
loss?
As far as I can tell "B" stands for Bull shiter :) Also the
O-rings
he is talking
about did not come from Creavey and I have no idea what size
they are.
----------------------------------------------------------------------------
-
I take it back about "B" and I apologize to him. I checked
back on
the old messages
and he was on the list for awhile. His name (I think) is
Brian D.
Cain. He seems reasonable.
What he apparently refuses to do is store the TES O-rings on a
board
for a few days
to flatten them before using. This is IMHO absolutely
essential.
Also people complaining
about over heating with these TES O-rings are not
pressurizing the
cooling system to check
for internal leaks. All real mechanics know how to do that.
Over
heating can be caused by a
myriad of factors of course.
The TES O-ring splitting is unheard of using Creavey O-rings.
Somebody somewhere
has a quality control problem. It could be Creavey as I
don't know
where these
TES O-rings were purchased. Looking at the McMaster TES
O-rings one
can tell they
obviously are made by some one other than Creavey. Perhaps
made in
China.
Mic those O-rings when you get them for being the proper size.
Paul Lamar ...No rotor no motor.
Paul,
I'm wondering if the engines that had problems also had lapped side
housings. It looked to me that at least one of the TES o-rings were
pinched and later failed. If you grind/lap the side housings a few
thousandths, wouldn't you need to change to smaller cross-section
o-rings?
BTW, my TES o-rings were easy to install, once I got the correct
lengths. No leaks either, and I'm running a 25# pressure cap. I
used
Hylomar to hold them in place. The guys on the No Pistons list talk
about using Vaseline. Maybe that's why they're having trouble?
Just a
guess...
Mark St.
A few thou should not make a difference. 10 thou or more is another
matter.
Vaseline is the Mazda recommended stuff. The main seal is metal
to metal
as Hylomar won't take that heat directly. I know people use it and
get away with it but I would not recommend it for this application.
The O-rings are there to keep the coolant in the water jacket and
not seal the combustion gases. However even the stock square seals
have a
layer of Teflon on one side. Mazda calls it white paint in the shop
manuals
but it is Teflon which becomes obvious when they are removed from a
used engine.
The Teflon goes on the OUTSIDE of the seal because of the exhaust
gases
recirculated in the rotor and end housings are very close to the
O-rings... I think.
No oil is allowed on the silcone rubber as silcone is attacked by
hydro carbons. That is another reason TES O-rings are better.
Paul Lamar ...No rotor no motor.
Reminder.. Please sign your posts..
Thanks,
Matt-
Hi guys,
I'm still a member of this newsletter. Have been since 1998. Since I'm
finally responding to the few posts, I'd like to have a chance to defend
myself against a couple of things that were said as well as comment about
the original thread I created on NoPistons.com.
I'm not a shill. Never heard the term before, but based on Paul's
explanation, it doesn't fit me in the slightest. I'm a personal business
owner and have been for 5 years. I have no particular relationship
with any other business that would otherwise preclude me being
someone who'd commit some sort of product espionage or false
advertisement, etc. Quite frankly, that's ridiculous. I'm a guy
who builds rotary engines for the street car enthusiast as well as a
guy who travels the nation tuning these things typically for power
production. My interests therefore involve the use of good, high
quality products. "I don't build junk" is a phrase I use with most
people who've never met me who are also considering doing business
with me. My name is too important to me to be put on stuff that I've
built that'll fall apart in short order. I take my work very seriously.
This
is what I live to do.
Which leads me to the reasons why I posted what I did about the
Rotary Aviation o-ring set. There's no malice intended here. I don't
have any personal beef against Laura or Tracy Crook; on the contrary,
they seem like real nice people. There's also no promotion of another
product by way of proxy here. It's a straight-up, customer-oriented
review of their o-ring product. Up until fall of last year, I was a very
consistent user of their o-ring kit and had been since late '03. I'd
used
them in almost every engine I'd built in that period of time. In my
opinion,
based on the steady use of their product for that nearly 3-year period of
time,
I think it makes me a pretty good customer and certainly someone who's
worthy to give his input. Their response to my complaint wasn't
reasonable,
atleast whomever the person was who responded to the individual on that
forum that forwarded them the thread wasn't. I would think the proper
one would be somewhere in the neighbourhood of wanting to in the least
take a look at the issue and see if it has merit, let alone take
measures to
fix the problem so it doesn't occur again.
Paul, what kind of details am I leaving out? I thought I'd described
this failure and my theories behind why quite well. I feel as if the
array of pictures I've posted speak for themselves. Is there something
else that you'd like to know about that might help form a better opinion?
You also mentioned that I should be storing (forming) these o-rings
around a wooden template as per pictured on your website.
http://www.rotaryeng.net/O-ring-size2.html Like I've already mentioned,
why in the world should I? Do you see any information on their website
that demands any such thing?
http://www.rotaryaviation.com/o-ring_kits.htm
I sure don't. Let's look at a couple of other factors: One, this o-ring
kit is
made to be easily purchased. They've got Paypal links on there.
Secondly, it's evident that these kits are targetted for not just the
aircraft
guys but also car guys like myself. Therefore, the target market is much
more broad and encompassing. If there's supposed to be some sort of
instruction when it comes to the "proper" installation of these o-rings,
given the target market, does it seem therefore reasonable that they're
at fault for not providing that said instruction? They're selling the
product;
it's their responsibility to serve their market rightly. How in the
world
can
a guy like me or anyone else for that matter be blamed for their o-rings
going bad, all the while ignoring the clear evidence of the teflon
jacketting
splitting long-ways for no apparent reason? I'm not at fault for not
building
some wooden template. I can't read minds, and when I buy a product
that's clearly advertised for the engine I'm using, that lacks *any*
other
(allegedly) critical information regarding its installation and use, why
should I
be held responsible? That's silly.
I don't know who the manufacturer of these o-rings is and quite frankly
I don't care. I'm an engine builder and a customer and I demand
satisfaction from not only what I buy for myself but also
what I buy and therefore build for others that has my name on it. I'm
still
very upset from the fact that I've had to shell out money of my own to
repair several engines now (the count is up to 7) because of the
glaringly
obvious defect of this product, whether it be a material or application
error.
Having to tear a motor apart because of an o-ring that splits along the
edge,
having nothing to do with installation, is just absurd. I'm also still
upset
at RA's very arrogant and condescending response to my complaint about
their product, implying that since I'm not a "commercial builder", or
however they exactly characterised it, and since they've only seen
some ridiculous
"0.001% failure rate" that my complaint (implicitly) therefore doesn't
matter. What hogwash.
Someone mentioned that I seem reasonable. I like to think I am as
I believe the strength of an argument rests solely on its merits. Here's
a (hopefully) reasonable question, I think: Given the vastly higher
standard of quality and workmanship that's demanded in aircraft use
vs. that of automotive, wouldn't it be reasonable to suggest that not
only these o-rings be applied (or manufactured, whichever it is)
correctly,
but also be sold and delivered in a way that's replete with this said
"instruction" of forming them for the factory o-ring land and anything
else for that matter?? You guys are using these in airplanes, for crying
out loud. Have an odd overheating symptom that produces an
out-of-nowhere,
symptomatically stratospheric water temp or rock-hard radiator hoses for
no apparent reason?
Good luck pulling over to check why while at 10,000ft.
B
___________________________________________________________________________
Brian D. Cain -/- Dallas/Ft. Worth, TX -/- bdc@bdcmotorsports.com
BDC Motorsports | Performance Rotary Engines, Specialized Porting, EFI
System Installation & Tuning
http://www.bdcmotorsports.com -/- http://bdc.cyberosity.com
The only missing information I need to know about Brian is the exact
section diameter of the O-rings shipped to you. I would like to know
who supplied them to Tracy so we can avoid that source but so far
he is not fourth coming with that info. I have in the past recommended
only Creavey as we had some bad results with McMaster Carr.
Again I am sorry about the bad things I said about you after reading
the no pistons post.
Paul Lamar ...No rotor no motor.
Paul,
There are two methods in common use for applying the Teflon coating to a
cylindrical substrate. An older method involves a spiral or helical
wrap of Teflon ribbon. When the wrap is complete, the adjoining edges
of ribbon are fused someway to form a continuous covering. If one
examines a variety of Teflon insulated wire samples some will clearly
show this helical wrap pattern in the insulation. A newer method that
is more difficult and more costly involves extruding the Teflon onto the
surface of the substrate to form a continuous and seamless coating.
The cracks that are apparent in these two photos that Brian posted seem
to indicate a helical pattern. Rotary Aviation could have received a
batch of defective O-ring material or received the wrong material
(wrapped instead of extruded). It may be worthwhile to destructively
test some samples of TES O-ring material to see if cracks similar to
those shown in Brian's photos can be produced.
Aubrey Thompson
In the case of Creavey I think the Teflon is extruded first and the silicone
is
injected in the liquid state. This is probably done in a mold so the
pressure
required to inject the silicone does not expand the Teflon. I could be
wrong.
On the other hand I think air may be required to convert liquid silicone to
the rubber state. That is why they call it RTV or Room Temperature
Vulcanizing
I think.
These picture you attached look like very poor workmanship was used to make
these O-rings.
I have never seen a TES O-ring that looked anywhere near that bad including
the
ones we bought from McMaster car. Creavey quality control on the other hand
is
excellent. It is on the cool side of the engine as well. The O-rings look to
be the proper cross section size however. Perhaps they were well under
diameter
and somebody stretched them to fit. If you try to do this one section of
the Teflon will yield while the rest of it remains the same. Perhaps this
is what happened some where along the line.
I have always thought of rubber, and that includes silicone, as being
"compressible".
What has been brought home to me after reading some bad O-ring experiences
years ago
is; rubber is no more "compressible" than hydraulic fluid. Furthermore
silicone expands
greatly when heated. If it is contained in a closed chamber without
expansion room such as an
O-ring slot it will generate tremendous forces. Enough to crack cast iron
and bend steel.
Therefore it is extremely important to have the right section diameter when
installing
O-rings.
If the O-ring is oversize for the slot the process of tightening down the
tension
bolts will cause the hydraulic force of the rubber to break the cast iron
end housings.
The problem will compound itself when the engine is warmed up to operating
temperature
as the silicone expands.
The last picture is what happens when the TES O-ring is too large in section
diameter for the size of the slot. You can see that the Teflon was cold
extruded
into the space between housings prior to final torquing of the tension
bolts.
The date on this photo is March 2003.
Paul Lamar ...No rotor no motor.
Now I'm getting very concerned! I've installed these o rings in my 20B and
now I'm wondering if I should tear it down and replace them with factory o
rings. I'm getting very close to my engine installation and would rather do
it now than after the installation. Do we know of success stories with these
o rings? Or should I just change them...
Bob Mears
Supermarine Spitfire
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