tom jelly wrote:

Saw this on the RX list:

To: rx7@world.std.com
Subject: (rx7) [all] cracked tension bolt heads

tonight i've been dressing down my 13BT engine in preparation for a
rebuild, and got to the point of removing the tension bolts.

i broke them free in the FSM prescribed order with an initial 90 degree
turn on the first 18 bolt cycle and 180 degrees on the second cycle.
as i began threading them out by hand, i noticed that the heads of the
majority of the bolts have radial cracking.  i checked some previous
photos of my progress and saw the the cracks had been there prior to my
un-tensioning.

so, a few questions:
does this cracking mean that i now have a set of 18 really cool
shishkabob skewers?
if so, can i use used tension bolts from another engine?
what would have caused this cracking?  improper untensioning from a
previous rebuild?

thanks!

matt baron

 Matt,
 Can you take some pix of the bolt heads and send them in?  Are you
sure they are cracks (sorry if that sounds patronizing, but often things
look like cracks but aren't)?

If they really are cracks, sounds bad, but I'm sure the rotor-motor
experts will have some experience to pass along.

Bill Freeman
Long EZ builder & pilot
BSME, MSME
EAA Technical Counselor

He is not on the list Bill. That was uploaded by someone else.
Jon hit the nail on the head so to speak :-)>

Paul Lamar
 
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