One Aztec engine with a chrome rebuild reached 27 hours and was still
pumping like it thought it was hooked to an oil well... Mechanic said the
cylinders were glazed and it would require a tear down, hone job, etc...
The owner blanched and plaintively asked if anything could be done to avoid
that expense... He said he would pick up the bills..
Filled it with synthetic oil, took it up it to 8500 feet , full throttle,
redline RPM, leaned to best power, and flew it from Michigan to Mena,
Arkansas.... It was 3 quarts down when landed... Took care of business,
refueled and reoiled, and it burned less than a half quart at normal cruise
coming back to Michigan that night......
Denny
"Larry Smith" wrote in message
...

"Dan Luke" wrote in message
...
"Baron Man" wrote:
i flew yesterday at 25/25 at relatively lower
altitudes - higher atm pressure.

You are correct to run at high power settings to seat the rings. Most
authorities I have read also recommend varying the rpm setting on
engines with constant speed props.

It is also critically important to keep the cylinders cool to avoid
glazing. Run rich and keep the cowl flaps open.
--
Dan
C172RG at BFM
(remove pants to reply by email)

We are breaking in channel chrome cylinders by running at 80% power, or
2600
rpm, with redline at 2700 on an O-300 Continental in a Cessna 172. An
old
friend and A&P advised running full barrel and monitoring the cylinder
head
temperatures with under-the-sparkplug senders until the cylinders begin to
cool. So far we have about 2 hours on the engine and the cylinders are
still not happy.

Steel cylinders usually break right in after only a few hours. Chrome is
a
quirkier break-in and sometimes fraught with problems. Keeping the rpms
up
and watching that CHT is critical, imho.