In article ,
"G.R. Patterson III" wrote:

Frode Berg wrote:

When you say "overhaul", what does this imply?
Is it an engine change, or just a major visit to the shop going through
everything and changing whatever is needed?

As Bob Noel says, they take the engine apart and make sure that every part
meets
the specifications for reinstallation (the "service limits"). Some people
prefer
to make sure that all parts meet the specifications for new parts. The key is
that this can be done by any competent mechanic; the engine does not have to
go
back to Lycoming or Continental.

Shop policies also differ. When Lycoming overhauls an engine, they replace
all
the cylinders and pistons with new ones. A local shop may recondition the old
cylinders and reuse them. A cylinder on something like an O-320 can typically
last 5,000 hours or so before it becomes risky to use it.

The bottom line is that getting an overhaul done by one of the major shops
can
save you several thousand dollars over getting one done by Lycoming, and
having
one done locally (called a "field overhaul") can save you even more. I've
even
known some people to overhaul the engine themselves. This requires that a
certified mechanic oversee the work.

That's the way i did my last overhaul. I had the cylinders ground .010"
oversize, installed all new bearings, valves, valve seats, pistons,
rings, lifters and followers, seals, etc. It is NOT rocket science! All
it really requires is the ability to use a torque wrench, common sense,
a source of parts.