Problem with nose wheel shimmy?

 

By LOUIE LACY (Llacy) on Sunday, January 20, 2002 - 06:37 pm: Edit

Does anyone have a diagram of the nose wheel spindle. I had a shimmy upon landing today and I think I have the washers and spacers in the wrong order. Also what is the torque on the castle nut holding the nose wheel on.
llacy@netease.net

 

My reply to Louie.

Hi Louie,

There never was a diagram for the assembly of the nose wheel bearings and spindle assembly that I know of. It is a tough one because there needs to be a spacer inside between the bearings so that the bearing cones are held tightly and not allowed to turn. I made a spacer of tubing and did the best I could the first time. However, I found that I had left too much play (the bearings were loose) and after this last incident of wiping out the nose gear and having to rebuild it, I did it correctly. It is a matter of careful measurements and trial and error.

 

The torque on the castle nut should be enough so it requires about 25 to 30 lbs at the rear of the fairing to move the assembly side to side. Too loose and you will probably get a shimmy. It needs to be tight enough so the wheel will stay in position once you leave the ground assuming you were tracking straight down the runway. Too tight and it will be difficult to steer on the ground with the tow bar.  The washers should be assembled with the flat washer first,  then the curved washer (Bellevue washer I think)(curve up) and then the nut. I assume you have the fiber washer at the top installed and in correctly. This last time I also put a grease fitting in the spindle area so I could get some lube in after assembling the unit. The new factory parts have the grease fitting hole drilled and threaded in the center of the front of the yoke.

Cheers,   Jerry Sjostrand


           Louie's reply.

Jerry

It turns out I never did get or install the Belleview washer I talked to Larry yesterday and he is sending me the washer and a new felt washer. I haven't had a problem before I guess it was my landing in that 18 K cross wind. I don't know about you but cross winds " eat my lunch". I think this will fix the problem. Thanks for the info

Lou