To prevent the upper link turnbuckle on Model "40" Tricycle and Model "40" Standard Tractors from working out of adjustment during operation of the tractor, a special lock nut (M2515T) is now being used on the rear (right-hand thread) member of the top link assembly.

This lock nut is drilled and tapped at an angle from the locking surface, so that it provides a positive lock when tightened against the turnbuckle.

Use of the lock nut in production was effective with the following Serial Numbers:

   Model "40" Tricycle   40-72339
   Model "40" Standard   4OS-67460

It may be installed on Model "40" Tricycle Tractors starting with Serial No. 40-60001 and on Model "40" Standard Tractors starting with Serial No. 4OS-60001.

To install lock nut, remove rear adjusting link and screw nut onto link. (See Figure 2B). NOTE: If certain implements are used, it may be necessary to cut one inch from turnbuckle (Ml737T) and turnbuckle handle (AM1904T) to provide for minimum adjustment of top link. BE SURE TO CUT OFF TURNBUCKLE ON RIGHT-HAND THREADED END.