The International Cessna^® 170 Association

It seems the pin on my tail wheel spring shackle is worn. Does anyone know where the pin itself could be sourced, then pressed in? Am correct in assuming the pin just sits in the hole in the leaf spring?

0542108 is the part number

I believe there is an L-19 shackle for sale on eBay. It might be the same, I’m not sure.

As far as I can tell, the purpose of that pin is to keep the shackle from sliding down the spring, so there shouldn’t be a great amount of stress on it I made one out of a #8 screw, using my drill press and a file as a poor-man’s vertical lathe.

Don’t forget the sheet aluminum “chain guard” across the bottom.

dstates wrote:I believe there is an L-19 shackle for sale on eBay. It might be the same, I’m not sure.

The L-19 website is a more respectable source than Ebarf: airrepairinc.com

If you were to use an L-19 shackle I think you'd have to add a shim as the main tail leaf spring is thicker on the L-19. Could buy the shackle just for the pin I suppose but like Miles' idea of just making a replacement pin.

For years my until I got involved my partner simply placed a nice size ball bearing between the spring indent and the hole in the shackle left after pressing out what was left of the pin. It worked fine.

The smart ass new partner (me) didn't want to keep track of the ball bearing on disassembly so I, wasting my time according to my partner, made a new pin out of nothing special and pressed it in. Painted it and it looked brand new. Of course we made a log entry.

Part 17 guard is definitely missing, there are two extra washers in its place.

If it was mine, I would clean up the shackle bracket and find a soft round head steel rivet (that looks like the original) and is the correct diameter to fit in the spring hole and silver solder it in place.

Or fabricate a soft steel pin from rod stock of the correct diameter, round off the head area to look like the original and silver solder that in place.

The shackle bracket should be mild steel and not heat treated so silver soldering should not hurt anything, is permanent, but can be un-soldered and replaced if it ever wears out.

mmcmillan2 wrote:Part 17 guard is definitely missing, there are two extra washers in its place.

For those not familiar... the “Guard” (Item 17) is necessary to prevent the steering chain (which becomes slack in certain tight-steering or brake-assisted turns) from catching beneath the shackle and thereby preventing the tailwheel from following steering-commands. This has resulted in departures from the intended-path of the aircraft and departures from runways/taxiways.

The “guard” can be easily fabricated, and I’ve also seen a short piece of rubber fuel hose slipped onto the shackle-bolt beneath the leafspring to accomplish the task.

mmcmillan2 wrote:Part 17 guard is definitely missing, there are two extra washers in its place.

I don’t know if it was the one from the factory, but the wrinkled up one that came to me on the airplane was 0.016 aluminum, so that’s that I fabricated a new one out of.

FYI, the L19 part is the same dimensions as what I have installed on the plane. Does this fall under owner maintenance?

14 CFR Appendix A Part 43 C - 26

(26) Replacement or adjustment of nonstructural standard fasteners incidental to operations.

mmcmillan2 wrote:FYI, the L19 part is the same dimensions as what I have installed on the plane. Does this fall under owner maintenance?

14 CFR Appendix A Part 43 C - 26

(26) Replacement or adjustment of nonstructural standard fasteners incidental to operations.

It falls under 14CFR Part 43 Appdx Z, “Owner Discretion”.

Roger

Main spring looks old

mschlender wrote:Main spring looks old

How does one determine when it needs to be replaced? My limited spring knowledge is that springs wear from use (flexing back and forth), not so much tied to time. I agree, the paint does look old.