The International Cessna 170 Association

Good evening,

Took the 3200 apart and noticed it had all 5 springs installed. Additionally, the 3 posts were snapped loose from the (pressure plate?). I've looked at previous posts which indicate only 3 springs should be used on a 170(B). Would using 5 springs make it harder to steer the tailwheel?


KJM

5 vs 3 springs should not make it harder to steer IF you have the king pin nut adjusted so it doesn't. Resistance pressure is created by spring pressure, either 3 or 5 and adjusted by how tight the nut is on the king pin. Remember the Scott 3200 is an industrial castering wheel not necessarily designed for one intended use as a airplane tailwheel. It was apparently thought that 3 springs and average nut adjustment was right for a smaller lighter aircraft a category the 170 fits into. 5 springs is called for on a 180/185 and other heavier aircraft.

Without looking for specific instructions how to start adjusting the king pin, which I'm not sure exist, but I would look for anyway, I'd start where you think the wheel swivels nicely but with some drag. Fly the plane. If you get shimmy, tighten the nut a flat or 2 and try again. If not leave it alone or loosen a flat or 2 and try again. Of course doing this assumes you have a good mounting angle of the wheel which is dependent on the leaf springs. A tighter king pin adjustment can mask a bad mounting angle and a loose adjustment can make a mounting angle on the cusp of being bad, shimmy.

The Tyco Scott “ Shimmy Checklist” instruction sheet location in the maintenance section page 2 line 6 states “Castle nut torque ( both wheel and bracket) 15 inch lbs min then if required continue clockwise to access cotter pin hole.
I have 5 springs in my 3200 and I have one with 3 on the project.

I went from 5 to 3 springs at my last annual and haven’t noticed any difference.

Thank you all for the responses!