O300 crankshafts: The early 8-bolt cranks used on the A, B engines are sometimes difficult to locate, but the later C,D,E cranks are the same as in the TCM IO-360 engines and are current mfr.
There aren’t many airframe parts that cannot be found in airworthy condition. It’s a “daydream” exercise to imagine this thing as a mechanical device which requires an assembly-line of spare parts to be available. The airplane is sufficiently common and simple that most parts can be located or manufactured / fabricated.
Your location and registration may complicate things for you should you find you need only OEM parts with documentation, due to CAA regulations (the reason many aircraft outside the U.S. are kept on the FAA-registry which is more lenient regarding owner-produced-parts, and A&P inspection-for-airworthiness suitability.) But generally, your 170 B will be easily maintained with good parts availability, one of the attractive things about this model.
How you store your airplane will greatly affect continued airworthiness. For example, one complicated and uncommon mechanism is the rear bulkhead upon which the elevator bellcrank is mounted. If the airplane is stored outdoors and the flight controls not properly secured …if the elevator is allowed to “bang about” the bellcrank-forces can cause cracking of the bulkhead, and the bell-crank itself is a double-fitted/rivetted stamping not commonly available…. (Flight Controls and cabin doors should be properly restrained during storage and when left unattended outdoors, and Never use the dorsal-fin/fairing to push the rear of the airplane around sideways)….or the operator is careless about handling the aircraft/empennage/elevator….the bulkhead can develop cracks from the elevator being “slammed” about. This can be a troublesome repair not only for it’s accessibility but also the rarity of parts. It’s not impossible…but it’s not a failure one would want visited upon themselves.
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Empennage leading edges are often damaged from careless handling / impacts and can be scarce, but a B-model can often use parts from the L-19.
The rudder bellcrank assembly is often found cracked or corroded, but new manufacture can be found from suppliers such as Univair and Aircraft Spruce as well as L-19 suppliers like Air Repair, Inc.
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One reason the rudder and bellcrank can be damaged is improper securing… and that is not provided-for by Cessna in any convenient way. One method NOT to be used: Do not use the top/rudder counter-balance area to hold it to the vertical fin/stabilizer, as doing so can damage the lightly-constructed counterbalance and twist the rudder.
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Also, do not wedge anything at that bellcrank because the large surface area of the rudder will place excessive forces upon the hinge-area of the rudder.
(If you look closely at the background of the above-pic you can see how another airplane has locked it’s ailerons. This is a common method that many use. However this method requires diligence because the Manual Flap Mechanism has great mechanical advantage…and if the aileron locks are not removed beforehand and the flap are activated during preflight they can damage the ailerons and/or the locks themselves.)
The seat belt can be used to hold the yoke aft-and-to one-side to lock the elevator and ailerons….just slip it thru the yoke and pull it back snug.
A search of these forums will show the methods that hold the rudder by the trailing edge / nav-light structure and secure it to the outer horiz-stabiliser or similar. This is how I do it… Others do it similarly using a leather “bra” at the nav light…. Either is good.
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And keep all those small hinge-bearings properly lubricated. While they are still available, they are not often available from Textron but from other suppliers….and under different part-names/numbers. Cross-referencing and locating a “CAA-approved” supplier might be troublesome. (U.S. registered airplanes can often use commercially available sources that G-registrations may not.)
Anyway, don’t become too worried about parts availability. The Members and participants of this Assoc’n are a resource that can likely assist in any parts you might need to locate. Again, Welcome!
(and post some pictures!)
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. I’d like to keep her in tip top shape so as I can eek out the remainder of my flying days hence my questions.
My wife can deal with it then