National Mower Triplex-CE DL 68" - Manual (Page 14)

68OMCE-10/01-350
14
BED KNIFE REPLACEMENT
FIGURE F
When the bed knife becomes damaged or too worn to
keep sharp, it must be replaced. Design improvements
have made bed knife replacement easier with bolt-on
construction. Follow the procedure below.
1. The backbar (1, Fig. F), bed knife (2, Fig. F) and
fasteners have been assembled at the factory under
tension. To ease replacement and prevent misalign-
ment of components, the leading edge of the backbar
must be tack welded two or three places before the old
fasteners are removed.
2. Remove shoulder nuts (3, Fig. F) and flat head
screws (4, Fig. F). If shoulder nuts are badly rusted or
corroded, they may have to be cut off and screws
driven out to be removed.
3. Clean the bottom surface of the backbar for
maximum metal contact with the new bed bar.
4. Fasten the new bed knife to the bottom of the
backbar in the position shown (bent edge up). Shoul-
der of shoulder nuts must be seated firmly in the
backbar and screws must be flush with the bottom of
the bed knife.
5. Torque shoulder nuts 35 to 40 ft/lbs.