After sending my Lycoming AEIO-540 to the factory for a mandatory repair it
has finally returned. At Oshkosh this year the people at the Lycoming booth
swore it would take only two weeks, but when the actual paperwork arrived
everything said one month in the shop. It ended up taking a little over a
month, from the day it was crated by my mechanic to the day it was returned.

Lycoming says they will pay for the costs of removing and remounting the
engine, along with the shipping as well as the repairs. Mine only had a
little over 300TT. I guess they figure the costs of the new crankshafts as
well as the repairs for all of the engines would be a lot cheaper than
series of very expensive product liability lawsuits!

Anyway, it looks like it'll need mineral oil for a while, and then there's
also the risk of something else working loose or breaking after the removal
and install- we'll have to wait and see in this regard. I may take it and
run it hard for a few hours, and then take it back to the mechanic to pull
the cowling and make sure everything stayed tight.

I've heard a lot of different advice on breaking in a new engine- run at
full power, don't run at any power for a long period of time, vary the power
settings (MP and prop), etc. Any advice? When do you switch back to regular
detergent oil?