Posted for "colyncase on earthlink"
<colyncase@earthlink.net>:
Jim,
thanks
for the post.
Is it correct that this
engine had no special work done to the valves when
it was built?
Colyn, this was and
brand new engine built in Feb. 2001 supplied through Lancair with the full
Lancair baffling. Since then they have changed some baffling but not much. No
special work was done on the original engine. When the new cylinders were
received from the factory I wanted the valves disassembled and the valves Lapped
in and pressure checked. The most interesting thing here was that TWO of the new
cylinders did not lap in and required cutting the seats to get a lapped full
seat. This is what I expect was the problem with the first cylinders and why 3
exhaust valves failed. The engine requires a full wide seat, not racers three
angled narrow seat, to get the heat out of the valve head, otherwise the heat
has to go down the stem and that causes the stem and guides to fail. The other
solution is to pull the power back and make a Bonanza out of our fast
machines.
Other tsio-550 drivers,
How
far are people getting without having to replace cylinders or do
other
overhaul work?
Anyone get past 1000 hours
yet? TBO?
I have heard of 800 hrs and one at 900
hrs that ran at 29/2400 most of the time.
JIM
Colyn