Making Adjustments - MTD 430-439 Series Operator's Manual

• Before reassembling the blade and the blade
adapter to the unit, lubricate the engine crankshaft
and the inner surface of the blade adapter with light
oil (or engine oil). Also lubricate the bolt holes, bolts
and inner surface of the nuts.
• Install the blade adapter on the crankshaft with the
"star" away from the engine. Refer to Figure 17.
Place the blade with the side marked bottom (or
with part number) facing away from the adapter.
• Align the blade bell support over the blade with the
tabs in the holes of the blade and insert the hex
bolt. Tighten the hex bolt to the torque listed in the
"Blade Mounting Torque" section below.
Blade Mounting Torque
Center Bolt: 450 in. lbs. min., 600 in. lbs. max.
To ensure safe operation, all nuts and
IMPORTANT:
bolts must be checked periodically for correct tightness.
SECTION 8: MAKING ADJUSTMENTS
Adjusting Handle Height
Your mower is shipped with the handle in the higher
height position. To lower height, proceed as follows.
• Remove the starter rope from the rope guide.
• Remove the upper handle by removing the hand
knobs and carriage bolts. Lay upper handle out of
the way, being careful not to bend or kink cables.
• Remove the hairpin clips from the weld pins on the
handle brackets. Refer to Figure 4. Press out on the
legs of the lower handle. Remove lower handle
from the mower.
• Turn the lower handle
around so the notch on
the bottom of the lower
handle is facing forward
as shown in the box
here. Reassemble,
placing the bottom
holes in the handle over
the weld pins in the
handle mounting
bracket.
• Reassemble the upper
handle to the lower handle.
• Insert hairpin clips in the inner holes of the weld
pins and attach the starter rope as instructed in the
"Assembling Your Lawn Mower" section.
Adjusting Cutting Height
All wheels must be placed in the same
IMPORTANT:
relative position. For rough or uneven lawns, move the
Notch
Lower
Handle
Replacing Rear Flap
• To remove rear flap, cut off the flat end of the wire
rod which secures it to the deck. See Figure 19 .
• Attach the new flap and new rod to deck, bending
the ends of the new rod over to secure to deck.
Rear Discharge
Door
Handle
Bracket
height adjustment lever to a higher position. This will
help stop scalping of the grass.
An adjusting plate and
thumb lever at each wheel
position provides cutting
height adjustment. Each
adjusting plate has nine
height positions. Height of
cut will change when you
move the thumb lever
from one position to
another.
• Simply depress the
lever towards the
wheel and move the lever assembly to desired
position. See the illustration in the box above.
Adjusting Carburetor
NOTE: A dirty air cleaner may cause an engine to run
rough too. Make sure that the air cleaner is clean and
attached to the carburetor before deciding to adjust the
carburetor.
WARNING:
the engine (e.g. carburetor) while the engine is
running, keep clear of all moving parts. Be
careful of heated surfaces like the muffler.
To adjust carburetor, please follow the engine manual.
14
Handle
Bracket
Rear Flap
Figure 19
Adjustment
Lever
If any adjustments are made to