Q: I’d like to know how old this O-35-C1 actually is. The Serial No L-605-15 may be revealing to you, but the online Lycoming lookup does not have it.
I wonder if it’s of interest because it’s so old? I presume it is from the early 1940s.
I bought it for $1,000 only as a display engine from a guy who pulled it off of his grandfather’s work bench. It’s not totally complete — it’s missing one Scintilla mag and various small parts. I don’t have any other history on the engine.
Larry G. Keast, PE
A: Larry, this engine was shipped from Lycoming on July 30, 1946.
I have no further information on it, but I can tell you, there are still many engines from this era still flying and even though parts may be a little hard to find, they are still out there.
This engine may very well be able to be overhauled and put back in service, providing you have the engine logbook.
From AC 43-9C, page 3:
“1. Section 91.417(a)(2)(i). Requires a record of total time in service to be kept for the airframe, each engine, and each propeller. Part 1, § 1.1, Definitions, defines time in service, with respect to maintenance time records, as that time from the moment an aircraft leaves the surface of the earth until it touches down at the next point of landing. Section 43.9 does not require this to be part of the entries for maintenance, preventive maintenance, rebuilding, or alterations. However, § 43.11 requires maintenance personnel to make it a part of the entries for inspections made under parts 91, 125, and time in service in all entries.
(a) Some circumstances impact the owner’s or operator’s ability to comply with
§ 91.417(a)(2)(i). For example, in the case of rebuilt engines, the owner or operator would not have a way of knowing the total time in service, since § 91.421 permits the maintenance record to be discontinued and the engine time to be started at zero. In this case, the maintenance record and time in service subsequent to the rebuild comprise a satisfactory record.”
I don’t see any reason the engine can’t be used in a certified aircraft based on this guidance from the FAA. Note that the AC specifically says “rebuilt”, not “overhauled”. Call your local FSDO, ask to speak to an aviation maintenance inspector, and get their interpretation.
the cylinders are the same as an Lyc.0-435 and many are still flying certificated a/c.
Come on folks. While not ideal log books get damaged or lost occasionally. If a powerplant mechanic overhauls this to serviceable specs per the current Lycoming SBs and manual that mechanic can start a new log book. It is overhauled and returned to service. During that overhaul all ferrous (steel) parts will be magnaflux and dimensionally inspected. All the other parts will be dye penetrant and dimensionally inspected. Some parts like exhaust valves will likely be new. When it is complete and the logbook signed correctly that engine has a tbo (RECOMMENDED time between overhaul) of 2,400 hrs and is one of the toughest working little engines in the business they were stock on the great little piper PA22-108 Colt, some of the PA18 Super Cubs and the Piper J5C/PA12 Super Cruiser many of which are still very much in Service. See this months AOPA magazine focus on the Short Wing Pipers.
OK. Let’s say the TBO is 2400 hours. Let’s say a licensed mechanic overhauls the engine per approved procedures. Let’s say a new logbook is initiated as a replacement. Now, what is the total time on the engine? There are no prior maintenance records to establish that!
I have an engine on a plane I bought what doesn’t have the original logbook. All I got was a book starting with a major overhaul from a licensed repair station. Once you send one in, especially to the manufacturer, about the only thing you often end up with after is the original case but if it measures and tests within tolerances, it shouldn’t be a big issue.
The engine could be used to power an experimental aircraft, such as amateur-built, if it is put back “into a condition for safe operation”. In cases such as this, we used to ask the builder to initiate a new logbook, and to remove the original engine data plate and install one of the builder’s design, such as:
Make: Sam Smith
Model: O-235 Pop ‘n Snap
Serial: 001
We’d also ask the builder to return the original plate to the OEM.
Could you put it into service in an experimental without a log book?