Yetter 2987 NH3 Magnum - Manual (Page 17)

17
OPERATION MAINTENANCE
BEARING ADJUSTMENT:
1. Raise the toolbar until the blade is clear of the ground. Place a safety stand under the
toolbar. Remove the blade. Remove the hub cap, cotter pin, slotted nut, washer and
spacer from the spindle shaft assembly.
2. Pull the coulter spindle shaft assembly from the hub. Remove bearing cones and seal.
3. Wash the old grease from the hub, bearing cups, coulter spindle shaft, seal and bearing
cones. Inspect the condition of bearing cups, cones and seal. Replace if necessary.
4. Apply #2 multi-purpose lithium grease on each bearing. Make sure the space around
each roller is filled. Lubricate the bearing cups.
5. Position the bearing in the cup and install the seal. Lubricate the seal lips and proceed
with re-assembly of the removed parts including the blade. Blade bolt torque is 90 to 96
ft/lbs.
6. Tighten the slotted nut to 10 to 15 ft/lbs. or until a definite drag is felt when the blade is
turned by hand. Back off the nut one slot position to line up the cotter pin hole with a slot.
Secure the nut with a new cotter pin.
KNIFE WEAR:
The lower portion of the scraper and tube are subject to wear during operation. The rate of
wear will depend on a variety of factors and in abrasive hard soil conditions the wear will be
more rapid.
NOTE: In certain areas, replacement knives should be kept in stock, replacing worn knives
as needed.
ADJUST KNIFE TO BLADE CONTACT on each opener so the blade will turn by hand with
slight resistance, but will not coast or freewheel. In loose soil the knife adjustment is
critical. If adjustment is not maintained, soil or residue may wedge between knife and
blade, resulting in the blade not turning. Because of blade run out, rotate the blade one
full revolution after adjustment. Re-adjust knife as needed. Never strike the knife with a
heavy object or damage may occur.
To adjust use shims or to adjust knife mounting out make adjustment to the nut on top of
spring for tension on blades.