Documentation
Our library of information and data on
the Merlin engine is second to none. In addition to the standard
military overhaul manuals, we have the complete set of books and
documents utilized by Bristol Aero Engines for overhaul of the
Merlin engines all through the 50’s up to the early 60’s. This
documentation was developed and updated continuously by Bristol and
Rolls Royce engineers, with many of the overhaul procedures,
modifications, and repair schemes applicable back to the war time
engines.
This set of data includes;
- Overhaul manuals, most models
- Bristol engineering instructions
- Packard service letters
- Modification manuals
- Reclamation & salvage data
- Parts books, most models
- Rolls Royce service bulletins
- Interchangeable parts list
In all, more than 70 books and manuals
with very detailed information on overhaul, inspection, test,
modifications, and repair of the Merlin engine. This data was
accumulated by Rolls Royce and Bristol Aero Engines, over many years
operating and overhauling the Merlin engines both in military and
civilian transport aircraft.
One example of this information, is a
temperature investigation study, performed by Rolls Royce on the
Merlin 600 series cylinder heads. The engineers drilled holes in the
cylinder heads and inserted temperature probes, recording and
charting the temperatures at various operating conditions on both
new heads and examples with significant service time on them.
One of the findings concluded that the
build up of corrosion and scale in the coolant jackets inside the
heads, caused an increase in cylinder head temps from 70 deg C to
120 deg C, a very substantial amount.
We have repaired many cylinder heads
in our shop that have suffered heat damage, and upon inspection of
the coolant jackets, found layers of scale and corrosion.
Our findings, being consistent with
the Rolls Royce data, led us to the decision to remove the core
plugs from every cylinder head we bring in the shop, and grit blast
the coolant jackets to clean metal – as new condition, as just one
of the standard overhaul procedures we perform on every cylinder
head. This is a time consuming additional step, but we are confident
it will provide a longer service life with less chance of
compression loss due to heat damage.
