Would I be correct in assuming this could be an

infant mortality

problem. In other words, if it didn't show up soon

after engine

assembly, one might be ok?  My engine was running

it's hottest

the first few flights after overhaul because of

plugged rads.

Perry Mick

I would say that was a correct assumption. At least I

hope so.

Our original theory on why some of the 88-89 O-ring

lands cracked

was because of quality control... casting core shift.

This may

still be a factor.

snips..

Paul Lamar

YES!....I agree, so much, that you can substitute "FACT"
for assumption.

There seems to be a general consensus in believe that
what is being performed here is, simply an installation
of an O-ring???......WRONG!!!!......As you all
know, "There's no free ANYTHING" in life :-)
This is more a case of moulding a seal in place, in our
situation it would be SHAPING an existing seal in place.

For sucessfull results one should:
-Straighten out the seal (This is where you'd wish they
had a line painted down the center) and allow it to
relax for 24hrs in a comfortable ambient environment.
-When ready for installation, boil water in flat baking
pan, place seal in the water (Don't throw it in), for 15
minutes. In the meantime, warm up the housing with a Heat
Gun. Install o-ring in the groove and continue engine
assembly (Stacking). When ready, do the same to the next
seal and so on.
NOW comes the kicker.......PRIOR to tightening bolts, re-
warm housing seams with the Heat Gun and tighten, do not
TORQUE. When ready for torquing, RE-HEAT seams again
with Heat Gun and torque the suckers.
You now have a SHAPED seal in place.
Obviously this procedure is for the TFE seals only.

Believe me this is easier to perform than to explain.

                                       Butch

I think this is a bit overkill Butch. Hell if we all had to 
do this I don't think anybody would use TES O-rings :-)> 
I think what we have here is a simple case of the section diameter 
being too large to begin with.

Paul Lamar
 
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