The first Cherokees used variations of the Lycoming O-320 engine.
BY: Norm Goyer
Some older Cherokees make better family aircraft than other models. The best value has always been with the Cherokee 180. This model has a Lycoming O-360 engine which is considered one of the most reliable engines ever made. But pre-1970 engines had the trouble-prone 7/16” exhaust valves. Most have now been replaced, but there still might be some out there. These engines have an AD requiring a 500-hour inspection of these valves. These engines are TBO rated at only 1200 hours. Engines with the ½” exhaust valves do not have this AD and are rated at a TBO of 2000 hours, a significant increase. Personally, I wouldn’t consider any Lycoming 320 or 360 engine still equipped with 7/16” valves. Cherokee 180s built prior to 1970 also have an engine-redline rpm restriction of between 2150 and 2350 rpm. Engines operating in this rpm range could develop torsional vibration, which can cause propeller failure (blade breakage) under certain circumstances. Many other engine-propeller combinations also have this restriction. However, it shouldn’t alter the value of your aircraft.
The Lycoming O-360 engine had 180 hp and was installed in the outstanding Cherokee 180, a “best buy” in used aircraft
All existing Cherokees have a very varied history. The lucky ones were hangared and pampered; many others have spent their life camping out in nature, left where their owner stopped using them. Outdoor storage differs, from the acceptable very dry arid areas of the Southwest, to the unacceptable rain forests of the Northwest. Those stored near salt water can have significant corrosion damage to the interior structure. A 40-year-old Cherokee, with low total time, can be in worse condition than one with high-time, if it were flown often and well maintained. An aircraft needs to be flown; sitting on the ramp for months or even weeks at a time, and then run up for a few minutes is doing more harm than good. An engine needs to be flown for at least 45 minutes to an hour to insure that the oil reached a temperature that will burn off all the impurities and moisture caused by condensation from varying temperature extremes.
The Cherokee 235 used a IO-540, 235 hp engine. The engine illustrated is a modern 300 to 350 hp, TIO-540, used in many high performance aircraft.
The most important rule to follow when purchasing an aircraft is to have a well-qualified, certified mechanic evaluate the airframe, engine, instruments, interior of the rear fuselage and wings. This is necessary to check for corrosion or hidden damage history. It is also very important to check log books for AD compliance and proper logging of weight and balance for any added components. Do not attempt to do this yourself, unless you have a background in this type of aircraft inspection. Be prepared to spend up to a $1000 for a complete check on the aircraft’s current condition and past history. Believe me, if the plane is okay, you will have the peace of mind of knowing it; if not, you will have saved yourself what could end up being thousands of dollars.
The honor of building the largest, most powerful reciprocating engine ever belongs to Lycoming for its XR-7755 c.i., liquid-cooled, multi-bank radial engine, designed for the B-36, but never installed. A Pratt & Whitney was used instead, along with auxiliary jet engines. This restored 5,000 hp Lycoming is on display at the Air & Space Museum in Washington, D.C.
I recommend that you, or your agent, eyeball the aircraft first to get an easy “no way.” If the plane looks like it is in good condition, then call in the cavalry to really check it out. Don’t get suckered-in by a very low asking price. If the plane needs an engine overhaul, minor damage repair, paint and interior and an upgrade to instruments and avionics, the final “in-the-air-price” could be way beyond its real value. Don’t get upside down, on the ground, in any purchase, house, boat, car or airplane. You cannot believe how much it costs in 2009 to have others restore your dream airplane. A Cherokee is not and never will be a highly desired classic, like a Beechcraft Staggerwing. Even the lowly Cub could bring more money than a Cherokee Cruiser. Check out the current price Cherokees are being sold for, not the “asking price” but the “getting price” for a similar aircraft. That figure should be your absolute maximum restoration or purchase price. This plane will never exceed future active-market value.
The famous mid-1930s Cord auto, built by Auburn, had a very powerful Lycoming V-8 engine.
Lycoming also built an O-720 eight-cylinder, horizontally-opposed engine for their Piper Comanche 400. It was never used in any Cherokee model.
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