[snip]
BTW we took the engine to Mazdatrix and John disassembled it. Perry decided
to have John at Mazdatrix overhaul it. Sure enough the rotor housings
had shrunk and the O-rings were leaking combustion gases. Perry decided
to have John replace all the tension bolts with new ones at a cost of
$17.81 each or $302.77 since there could be fatigue cracks in some of the
rest of them. No point in taking chances. John claims the best tension bolts
are the 89-93 versions. John coats all year tension bolts with RTV
to damp bad vibrations.
Paul Lamar

Scott Speirer wrote:

OK, I still don't see where the 'sure enough' is coming from.  One tension bolt was
broken.  Some of the other tension bolts must be slightly elongated to allow any gap around
the O-rings.  Was it the tension bolt failure first, and then the O-rings, or first the
O-ring failures which then somehow, someway, caused the tension bolt failure.  Another very
lightly explanation is that the tension bolt failure and the O-ring failures are totally
unrelated.  The O-ring failures caused the cooling problems.  You just happened to discover
a broken tension bolt, as well.

Scott

Don't really know Scott. BTW a thermocouple buried down in the aluminum
around the spark plugs would go a long way towards determining
the exact temperature reached by the rotor housings. That is the bottom
line and that could be used to determine the necessary aux coolant flow
required to prevent rotor housing shrinkage in the event of a main coolant
system failure.

Paul Lamar
 
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