From: rod@sadtler.com (Rod Farlee)
Newsgroups: rec.aviation.owning
Subject: Engine book review (long)
Date: 6 Nov 92 05:58:40 GMT
Organization: Sadtler Research Laboratories


John Schwaner, "Sky Ranch Engineering Manual: Aircraft Piston
Engines: Operation, Failure, Repair", 2nd edition, 1991, 494pp, 
$19.95.  publisher: Sacramento Sky Ranch Inc., 6622 Freeport Blvd, 
Sacramento CA 95822.  order from: EAA Bookstore, (800) 843-3612.

The author is an engineer and operator of a large engine rebuilding
shop.  He draws on his experience rebuilding thousands of engines
to explain, diagnose, and help prevent the common failure modes of
Lycoming and Continental engines installed in light aircraft. 

The technophobe, seeking operating guidelines, not technical depth
or understanding, might prefer Kas Thomas' "Lightplane Maintenance 
Aircraft Engine Operating Guide" (TAB/McGraw-Hill, 1985, $14.95).

Schwaner's book addresses the technophile, who seeks a rich source 
of information on all the engine models and their accessories, how 
and why they were designed, how and why they fail, how to recognize 
and prevent problems, and how to evaluate what an A&P says when 
there is a problem.

This book's only shortcoming is a lack of organization and logical
development: its intent is to be a text, but is succeeds better as 
a reference work.  So this review will skip around, organizing the 
chapters into three groups: (1) how engines work, (2) how engines 
fail, (3) what to do about it.

(1) how engines work.

After the Introduction (piston engines, ignition, Lycoming and 
Continental specs), you might choose to skip directly to Chapter 11, 
"Forces, Vibration and Balance".  This describes the mechanical 
engineering design of piston engines.  Piston acceleration proceeds 
via Fourier analysis to crankshaft vibrational modes, torque and 
power curves, torsional balance, vibrational analysis, resonance, 
and coupling.  This is all at a "Scientific American" level for the 
technically literate layman; simple algebra is used.

Chapter 10, "Performance Limits", describes computation of power,
volumetric efficiency, prop loads, and power curves.  Chapter 3,
"Engine Performance", covers cooling, mixture, ignition systems,
fuel octane rating, detonation, diagnosis via cylinder head and 
exhaust gas temperature measurement, porting, efficency and power 
computation, and related operational topics.

(2) how engines fail.

After this detailed description of air-cooled engines, one can then
delve into what kills them: metal fatigue, corrosion and wear.

Chapter 1, "Fatigue Analysis", defines stress, strain and modulus
of metals,  residual compressive and tensile stress "built into" 
parts, and stress relief and annealing.  Surface finish, honing,
nitriding, magnafluxing, and specs for aircraft parts are described.
To help one recognize different types of fatigue failures, many 
pictures of failed Lycoming and Continental parts from his shop are
included.  The cause of each failure (flaw in part, its install-
ation, or operation) can often be deduced by visual examination.  

Chapter 6, "Fasteners & Failures", describes stress distribution
within bolts, nuts, and studs and analyzes their failure modes.
Effects of torque accuracy on through-rods and cylinder studs is
analyzed.  Teaches how to recognize the type and cause of failures,
and how to select and spec fasteners and install them correctly.

Chapter 5, "Lubricants & Wear", details how modern oils are
formulated to perform their functions: lubrication (hydrodynamic and
boundary), cleaning (dispersants), protection (oxidation inhibitors,
acid neutralization, metal chelates), sealing (viscosity), heat
conduction, etc.  Viscosity and the development of polymer additives
to produce multiviscosity oils are nicely reviewed.  Cylinder and
camshaft lubrication is discussed in detail, including the purpose 
of EP (extreme pressure) additives, the chemicals used (TCP, etc) 
and how they react with steel.  Mineral, semi- and synthetic oils 
and greases and their advantages and disadvantages are listed. 

These chapters detail how fatigue, corrosion and wear are factored
into engine design, and when design came up short, how they resulted
in specific airworthiness directives.

(3) what to do about it

With this information, we can now go put our hands on the hardware.

Chapter 2, "Engine Inspection", is a detailed 70-page tutorial on
what to look for, inside and out.  If a cylinder overheats, did 
you know that you can tell how hot it was within 20 degrees F from
the color of the surface oxide?  The source of every element in a 
spectroscopic oil analysis is listed.  Identifying metal particles
in the oil filter and their source and cause are detailed.  Bearing
and tappet clearances and specific problems to watch for on some
specific engine models are described. 

Chapter 4, "Cylinder Repairs", describes chroming, honing, valve
seating and alignment, ring seating and rotation, piston inspection,
line boring, and cylinder color coding for Lycoming and Continental.

Chapter 9, "Troubleshooting", alone is worth the price of the book.
Seventy specific problems are listed, along with all their possible
causes, how to determine the cause, and how to fix it.  Examples:
hard starting, kick back, rough idle, high oil pressure, high idle 
manifold pressure, high oil consumption, high EGT (on one cylinder,
on all), turbo controllers, carb and injector troubleshooting, and
turbo controllers.  Many notes refer to specific models: "Slight
hesitation or stumble on acceleration: Lycoming O-320-E2D on C-172 
and PA-28-151, Lycoming O-320-E2G on Grumman AA5 and AA5A: refer to 
Lycoming Service Instruction 1305C" which details how to check that 
the carb nozzle is the correct size.

Other topics covered are Hose Assemblies (Chapter 6), Calibration
(Chapter 8), list of 500 four and six Lycoming engine models and 
their specs (Appendix), a glossary and an index.  This book also
covers all engine accessories (fuel, oil and air pumps, carburetors,
magnetos, alternators).  Only a few selected service bulletins and 
airworthiness directives are mentioned, and then only as examples of 
particular problems, not listed by engine model.  References are 
primarily to engineering texts and ASTM journals, not to more 
accessible publications, books and articles.  The only error found 
is in Figure 3-18 (reactions of ethylene dibromide and tetraethyl 
lead are interchanged).

If the book is read in the order it is reviewed, the reader might
find some items that are not defined until later.  Unfortunately,
this will be even more true if the book is read from page 1 to page 
494.  The attentions of a good technical editor would have been 
very beneficial to this book.

Lacking only in pedagogical organization, any technically-oriented 
aircraft owner or pilot will find this book to be both a rewarding 
learning experience and valuable reference.  Highly recommended.

-- 
Rod Farlee, rod@sadtler.com, (215) 382-7800
Bio-Rad, Sadtler Div., 3316 Spring Garden St., Philadelphia PA 19104