Paul,
what led you guys to look at the tension bolts? Was coolant dripping from the
flywheel side housing?
Ed.          pebvjs@aol.com

We had given up after four test flights and trying different things.
We had finally accepted the worst scenario and concluded combustion gases
were leaking into the cooling system and blowing all the coolant overboard.
We were in the process of removing the engine when a part of the cowling
was removed that allowed us to see the bent tension bolt. 

Early today Perry remembered seeing a mystery piece of metal several months 
ago. Turned out that piece came from the broken bolt boss on the rear housing. That 
means the tension bolt broke several months ago and Perry had flown it many hours 
before it over heated in Palm Springs. We now are not sure what came first. It 
could be the engine overheated from a leak we found in a hose clamp area when 
we pressure tested the cold engine cooling system with the schrader valve 
adapter I made. See the properly rotated picture below.

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.

I need to look into custom ARP tension bolts. $17.18 each is a bit much
for stock Mazda tension bolts.

Paul Lamar
 
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