Outer O-ring slot is .115 wide and . 065 deep.
Again a little deeper I think. this is good news
as it give more room for the .093 O-rings.
The same .093" section diameter O-ring we are using
now should work fine.
I think the outer slot is a bit deeper than the 2nd gen
.065 but I think an .080" O-ring section diameter will work fine.
The width is a bit restrictive for a .093" diameter IMHO.
Of course all four O-ring slots are now in the rotor housing and not
in the end housings.
Paul Lamar
Paul,
The slot for the outer O-ring would be approx. 96% filled assuming a Ø.093
cross section. That is too much, especially when using a stiffer than standard
O-ring like the TES. Even using rubber O-ring I wouldn't suggest that. The
other question that begs to be asked is what size O-ring are people ordering?
Would the order be for an Ø.093 O-ring or for a 3/32." The reason I'm asking
is that Parker lists the 3/32 O-ring at Ø.103 if I remember right. All of the
standard sizes are .005-.010 oversized. That is NORMAL tooling to Parker. To
actually get a .093 O-ring you would have to get a special. FWIW.
I think it is kind of tough on Tracy to have a second party trashing his
stuff. If he offers the guy replacements or refunds on the kits it should have
this covered. Then getting the correct diameter in the kits if they are
incorrect to begin with would be vital. The problem were going to have is that the
O-ring in the stock engine is a special. The rectangular cross-section used
is unusual. All the standard O-ring charts show the slot about 85% filled.
This isn't a very high pressure environment either. most hyd. O-rings see
thousands of psi all the time. 30 psi should be nothing! off the bottom of the
gauge. We should also be checking if G was using anything other than vasoline,
or the Mazda assembly material. (thick Vaseline) The reason I mention it is
that people often put sealers in to hold the O-ring if nothing else. A slot
with just a little too much goop can get hydraulic lock and damage the O-ring
or the slot. This could happen even with the stock material. That would give a
overpressure failure even if the O-ring is the correct size. I'm mentioning
this as I would like to get to the bottom of the problem, not to take
anybody's side in the matter. I have often needed to remove silicone seal, or ultra
gray or other fillers when replacing O-rings. After cleanup most of the
engines never leaked again!
Bill Jepson
----------------------------------------------------------------
Yes I agree so far nobody that I know of has an outer TES O-ring. I could be wrong.
I think the .080 size might be better for the outer slot.
You are right on the money on the 3/32 and I warn people on the web site
about that.
http://www.rotaryeng.net/O-ring-size2.html
The Creavey's are not oversize. What you buy is what you get. In fact
I just measured a set and they were .001 under size.
It is his attitude that is pissing people off. He has not learned lesson number
one for being in business. The customer is always right.
His arrogant comment below about the section diameter is ridiculous.
Anybody that ordered the O-rings with a micrometer can measure the section
diameter. It would diffuse the situation if he just told us
what it was. Unless of course it was not the proper diameter.
People are going to assume that is probably the case.
"As to questions about the O-rings themselves, I don't have the time or
willingness to disclose every specification, process, material, etc that
goes into the products sold on my website (what company does?). If this
bothers you, my advice is not to buy them."
Putting sealers in is a big mistake as it can subtract from the available
volume. I also mention that in the article on the web site.
The storage board works great. Use it.
To give you an example of how far back this subject goes here is a message from
Jan 2nd 2001.
We had a good handle on this problem years ago. I am stunned that
people are now having trouble. Something MUST be seriously wrong.
Paul Lamar
----------------------------------------------------------------------
-------- Original Message --------
Subject: Rebuild Kits
Date: Tue, 02 Jan 2001 16:46:02 -0800
From: Paul
<rotaryeng@earthlink.net>
Ed Anderson wrote:
> > >
> > > Paul,
> > > Attached is photo of rear housing outer coolant "O" ring that fell
> out
> > > of its groove during installation of the rear housing and was cut into
> > > several pieces. Result was coolant leak between rear rotor housing
and
> rear
> > > side housing. Apparently too little Hylomar or perhaps a spot of oil
in
> the
> > > groove, but it required 7 hours to fix. Only about 20 minutes to
replace
> > > the seal, rest of time was removing/reinstalling engine and getting to
> the
> > > engine.
> > >
> > > Best Regards
> > >
> > > Ed
> > >
> >
> > That teflon encapsulated silicone inner seal still looks in good shape
> :-)
> > Perhaps it is worth biting the financial bullet and using those on the
> outer seal as well.
> >
> > Paul Lamar
> I agree, Paul. In fact I tried to find a Teflon coated O ring big enough
in
> size and could not find any. I found some burna? rings but they were 1/8"
> thick which is too large for the outer O ring. I will keep looking.
>
> Yes, the Teflon coated inner ring did not look too bad for the wear {:>).
> But even the Teflon coated O rings in the old engine were in the same
> condition. So my experience is the Teflon O rings are certainly they way
to
> go and getting them from McMasters at $9 and some change beats getting
them
> from Hayes at $25 a pop. If you recall from your visit, I have an 87
block
> sitting in the wooden stand that I will get around to rebuilding and
intend
> to use other than Mazda "O" rings where ever possible.
>
> Ed
I got some of the teflon encapsulated silicone outer rings from All O-rings
but they wanted much more money than McMaster Carr.
Paul Lamar
Andrew Mueller wrote:
I recently signed up to be on your mailing list for rotary conversions. I
am a rotary rebuilder for the automotive industry and am sifting through the
200+ emails I received over the last few days. I am responding to the
letter that was written below.
Are you aware that MAZDA will sell you a rebuild kit for rotaries...if you
know the part numbers up front? These kits come with everything except the
front and rear main seals and oil control rings and rubbers, and do not
include any parts to rebuild the rotors or any internal springs. What it
does have are the inner and outer water seals and ALL o-rings for the
completion of the engine, all for around &100 a kit. If you need part
numbers for these and other pieces, let me know, I'll be happy to give them
to you. Also, MAZDA parts are the best there are provided that, like any
other engine, yours is run within operating temps and pressures.
As for reusing the inner [stock] water seal, be very careful when removing the seal
if the engine has been fired up and heated in any way. As you may know this
multi-layered seal will separate and if it is reused in this condition, you
may experience a water leak some time in the future. And to ensure that the
seal lasts as long as possible, go to MAZDA and get the heat shields for the
inner seal. These are small slivers of creased metal that are placed along
the inner edge of the seal to help deflect some of the heat generated by the
combustion possess.
I know many tricks to building these engines. Things that you will not find
in any manual and I have little reason to keep them all to myself.
Andy Mueller
amueller@jps.net
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