Mark Steitle wrote:

Paul,
Sorry to bring this up again, but I could use a little help.  I recently
ordered TES o-rings from Creavey and they arrived yesterday.  The inner

and

outer oil o-rings fit perfect, but the outer coolant o-ring is too big by
about a 1/4".  Here's a quote from a recent message on this topic which is
where I got my measurements.

<snip>
 > 2. outer coolant oring -
 >
 > diameter = 11.340
 > slot depth = 0.062
 > slot width = 0.110
 > section size = 0.093
This is critical! The proper section size is .093. Not 3/32
as a 3/32 O-ring is bigger in section size than .093.
<snip>

Please explain what is meant by "diameter".  The measurement of 11.340" is
what I gave Creavey, but they took it as ID.  Now it looks like it is
actually the o-ring centerline to centerline measurement.  Is this
right?  I didn't know enough to correct it at the time.  Hopefully they

can

put them in their o-ring shrinker and make them smaller.  Would it be
better to provide them with the circumference measurement instead?  If so,
what is the correct circumference?  In recent postings I've seen 35.13,
35.31, and 35.62.

Thanks,
Mark S.

Sorry about that Mark. I think that is OD and not ID.
Is the engine apart? If so check the dimensions by measuring
the grooves. My slotted end housing is up at the hangar.

11.340 diameter center line is 35.62. 1/4 inch less on
the circumference would give a centerline diameter of 11.260.

11.340 minus the .1 slot width would be the ID or about
about 11.240 inner diameter. The circumference for that
would be 35.31.

You could cut a small chunk out of the outer ring and place the cut
on the cool side or the top of the engine with a little red RTV
silicone rubber and you will be fine. Or mail the outer back
to Creavey and asks them to make a set 3/8 inch smaller in circumference.
Also perhaps they can tell you what kind of glue they use to join the ends.

It is best if the O-ring is slightly undersize as you can pre stretch
it on a plywood board.

35.13 is probably the right circumference number.

Creavey should know by now what the proper sizes are.

Also mic the section of the outer ring and make sure it is
.093 and not any larger.

I may be forced into stocking these O-rings if we continue to be confused
about the proper sizes. I did not really want to go into business again
but it looks like that is what is happening with the intake manifold parts.

BTW Jeff Chrysler if you are reading this Mazda will sell 18,000 rotary
engine powered
RX8's next year in the US.

Paul Lamar

Jeff Chrysler wrote:

Hi Mark,

It is best if you send the o-rings back to be reworked. Silicone glue is not
very strong without the support of a Teflon jacket to hold it together.

The rings will be cut down and made to an 11.155" ID so that the ring OD
will be close to or snug with the outside groove diameter of 11.340.

If you wish the rings to be snug to the groove ID they can be cut down to
11.110" ID but this probably is not as ideal due to pressure traveling
outward.

Awaiting your answer.

Best regards,

Jeff Chrysler

There is your answer Mark. Jeff Chrysler of Creavey is our buddy :)

Paul Lamar
 
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