Here's a collection of scanned and re-typed manuals for various antique and sometimes not-so-antique aircraft parts.

First, check out VintageAircraftEngines.com, my companion site which contains many scanned engine manuals.

• 1936 Waco Custom Cabin Setting Up and Instruction Manual
• Aeromatic Propeller Field Service Manual
• Narco AT-50A Transponder

As I seem to be collecting planes that use Warner Scarab engines, here's a summary of the Warner engines that were built and service manuals for them:

Here's some random advice on Warners:

• Warner 165 Overhaul Tips - Charles Stobbart
• Warner 145 and 165 Tips - Dick Martin
• Care and Feeding of Warner 165 Engines - Jack Polk

As an aside, it is fascinating to watch one of the early Warners such as the 90 HP Scarab Jr. in action.  These engines, as well as most other early aviation radials, have exposed valve gear that hangs out in the breeze.  As a result, when the engine is running slowly at idle, you can see the valve actuation patterns "circling" around the engine.  I recommend the AAA Fly-in in Blakesburg, IA to catch one of these wonderful engines.

As always, use these at your own risk.  If you're looking for manuals, I suggest trying:

• Type clubs for the aircraft type in question.  The EAA has a list of type club addresses.
• Find a guru for the type and ask for advice.  Usually there's an informal network of knowledge about antique engines and airplanes, you just have to know who to talk to.
• The Antique Aircraft Association has a library of some manuals for antique aircraft.
• Get a current issue of Trade-A-Plane and there are generally several ads for companies that specialize in manuals.
• I've had good luck dealing with Essco Aircraft, who specializes in aviation manuals.
• The Smithsonian Air and Space Museum archives has blueprints for many vintage types.  It takes a while and the blueprints are low-quality microfilm, but it is better than nothing.