Question for Paul McBride, the General Aviation News engines expert: I recently bought a project Stinson Station Wagon 108-3 that is equipped with an O-435 Lycoming engine.
Is there a way to determine if the engine is the O-435 190-hp or the O-435 225-hp? My engine serial number is L004093-8.
Tim Oshesky
Answer: Tim, it’s very difficult to research an engine this old, but my best guess is that your engine is probably a 190-hp engine.
The -8 series was the original series for the 435 engines, so my guess would be that the 225-hp engines came along at some later date.
The higher horsepower engines also had a different serial number suffix.
If accomplished with STC:
SA4-398
Serv-Aero Engineering Inc
Lycoming O-435-C
190 HP
What eye-candy a Stinson is. The only activity more enjoyable than looking at this Bird is flying it!
Check the engine logbook to see if the engine & airpl ane has an STC to up the hp. A search for STCs on the O435 engine might be a place to start.