are beefed up, and there is longer through-stud
engagement, eliminating an earlier weak point.
Main bearings are upgraded, and the rod bearings
are now grooved to provide more piston cooling
oil. Oh—in case you’re about to go order a bunch
of hot-rod parts for your old -A model,
Continental warns, “The higher compression ratio
pistons of the -D should only be used with the
beefed up -D crankcase.”
The lightened propeller flange has the same
bolt circle as TCM 550-series engines, but it’s
smaller than that of the O-200-A. This flange has
been tested only with metal hub propellers;
wooden propellers have not yet been qualified.
Though O-200-family engines have traditionally run 80/87 avgas at compression ratios from
the mid-6s to 7.0-to- 1, the D-model is pegged at
8. 5 and burns 100LL, and rated horsepower ( 100
at 2750 rpm) remains unchanged. The earlier
engines were rated at ± 2. 5 percent, while the
O-200-D is rated -0 + 5 percent. Continental’s chief
engineer, Bill Brogdon, explained simply, “The
O-200-D is a more powerful engine than the -A.
The -A version was probably near the bottom of
that minus 2. 5 percent, and we’re right up against
the plus 5 percent with the new engine.”
New O-200-D parts should start becoming available from TCM “fairly soon.”
The -D parts should be every bit as good as the old ones, or better, and many are
lighter. It remains to experimenters to determine which will work as direct plug-and-play parts with their older mates, and in which combinations, but the
originals are plenty good, with a long history of decent power-to-weight ratios,
plenty of aftermarket support, custom suppliers, experienced mechanics and
rebuild houses, moderate fuel consumption—and the ability to put smiles on the
faces of everyone from hard-core racers and builders to the kid who just soloed.
It’s difficult to make things stron-
ger while making them lighter,
but the new -D incorporates
substantial engineering and
Buying the new O-200-D
TCM is offering the O-200-D series to original
equipment manufacturers (including certificated,
light-sport aircraft, and 51 percent kit manufacturers), and it will also accommodate individual
experimental builders. Eventually the -D will get
into the retrofit market. Retail pricing for the
engine is $20,999. In addition, the Teledyne
Factory Service Center can supply a new O-200-A
through the TMX program: You furnish a certified
core, and you’ll get your dataplate back on an all-new (-A model) engine for $20,455. If you don’t
have a core, you’ll pay the same price and still get
an all-new engine, but it won’t be certified. There
are all kinds of running changes on the -A, so the
sage advice to look for the newest cylinders,
spring-loaded pushrod tubes, one-piece venturi,
Toll Free: 1-800-248-0638 ATS ENGINE TEST KIT AIRCRAFT TOOL SUPPLY COMPANY p/n EK5EM Lifetime Warranty
As a new addition to our EK5EM Kit, our new Compression Tester Extension may be just
what you need if you sometimes have trouble getting to the spark plug port for compression testing due to distance or obstructions.
The new ATS Engine Test Kit has all of the test equipment needed to check engine compression, synchronize magnetos, time aircraft engines, and test ignition leads all in one
The kit contains: the ATS 2EM Differential Pressure Tester with master Orifice, LED52 Electronic Magneto Synchronizer, Eastern E25 Aircraft Timing Indicator, Eastern E5 High Voltage Cable Tester, our new Compression Tester Extension & #19000 Hip Roof Tool Box.
It’s a replacement 18mm aviation plug adapter with an 8-1/2” reach to work around
manifolds, baffiling, harnesses, support structures, and anything else that gets in your
way. The T-handle lets you screw and unscrew the extender into the port without a wrench.
And finally, the quick connect coupler and the O-ring seal to protect the spark plug port
makes it a snap to hookup and disconnect your tester.