The Cylinder head is screwed on the cylinder like a big jar lid. I always
though that they used the old head with a new barrel, screwed it on tight,
then jig drilled the mounting holes is the flange of the barrel. I don't
know how one would index a new head with and old barrel. I suppose it could
be done with shim gaskets, but if you didn't get the right shim, the head
would not stop at the right place.


--
Cy Galley - Chair,
AirVenture Emergency Aircraft Repair
A Service Project of Chapter 75
EAA Safety Programs Editor - TC
EAA Sport Pilot
"Jim Carriere" wrote in message
...
Denny wrote:
pipe to line up... What the hey? Gets out a strong light (why do all
mechanics work in a shop that is dimmer than a confessional booth?) and
takes a look... The head was re-installed on the barrel ten degrees out
of alignment...

Out of curiosity, how does the head go on ten degrees (approximately or
exactly) out of alignment? I thought the bolts or studs would accurately
locate the head and jug every time, so obviously there is something I am
missing or don't know.