per·fi·dy
deliberate breach of faith or trust; faithlessness;
treachery: perfidy that goes unpunished.
Here is the last bit of data on my 170 hour IO-550 from
Performance Engines, now having completed final inspection and starting
rebuild.
The crankcase was cracked between the no. 5 cylinder and the
alternator. It was shipped to a crankcase specialist who found that while the
crack was repairable, measurements of the crankcase halves showed that one had
been already machined beyond limits so that its deck height was below
specification while the other half still had significant metal to permit
remachining. That is, they were far from matching one another, as required.
The remachining is required after weld to remove
distortion. It consist of two steps: first the mating halves are lightly cut,
and then the crankshaft bearing seats are remachined to make them round again.
One half was OK, the other already machined beyond limits. Since a cardinal
rule is to never mix crankcase halves, the one half causes the whole assembly
to become scrap.
So here we have a beyond limits crankcase that can be added
to the earlier list of parts that were found to be worn beyond limits, yet
reinstalled in my engine:
- The oil sump requires weld repair,
various dents, one significant chaff, and the thickness of the metal where
it has been modified around the drain hole is extremely thin.
- Oil filter stud is the old style
and needs to be replaced to incorporate the new style
- The starter shaft is worn beyond
manufactures limits, requires new shaft as it is already at the last
regrindable limit.
- The starter worm gear is worn
beyond manufactures limits, requires new gear as it is already at the last
regrindable limit.
- The starter worm shaft is excessively
worn / splayed at the starter motor engagement end requires a new or
serviceable shaft.
- The alternator face gear has wear
/ pitting on the teeth, requires new or serviceable gear.
- The connecting rods require
overhaul, as the big end tunnel bore is oval and stretched.
Add to this my refusal to reuse the 11 unbroken rocker arms
(at about $380 each), and you conclude that the engine was junk when it came
from Ron Munson’s shop, and it will be about $36K+ to bring it up to entirely
new standards.
What Performance Engines has done to us is beyond belief.
Dipping them in a boiling pot of well-used W100 oil would be appropriate.
Guys, as noted previously, we have to report our findings to
the FAA. Be sure to do so.
And be careful. There is stuff floating around out there
that could give you a very bad day – or much worse.
Furious but Chastened Fred, all limbs still connected and
functioning