Problem : Grass appears striped
Solution: Bent blade or worn spindle bearing are the most common causes. One
of the blade tips is cutting is cutting much lower than the rest of the cutting
surface . A visual inspection may not indicate a bent blade. From under the
deck, line up a blade tip with a reference point and keep your eye on that point
. Spin the blade to align other side of the blade with that same reference point.
If they line up exactly the blade is not bent. To check for a worn spindle,
rock the blade up and down from the blade tip. If movement is felt, the spindle
bearing is the likely cause.
Problem : Mower is leaving a strip of uncut grass
Solution: It is likely that one, or a combination, of the following five scenarios
is resulting in the uncut strips.
1) The wrong size blades have been installed.
2) The blades are installed upside down.
3) The blade tips are worn. To correct this, replace the blades.
4) Overlapping may be insufficient. The tires push down grass during each pass.
If you line up your tires with tire marks from the previous pass, the grass
does not get a chance to stand back up during either pass. Overlap more than
the width of your tires on subsequent passes. This will allow the blades to
draw up the trampled grass from each previous pass and should produce a nicer
looking cut.
5) Making sharp right hand turns. Twin-blade mower decks are designed with the
discharge on the right side and two side-by-side blades. The side-by-side twin
blade decks have the left hand blade positioned slightly forward and in front
of the right blade. This provides cutting overlap when traveling in a straight
line. As a result, the tractor should mainly operated making primarily left
hand turns when cutting. During left turns this cutting overlap is maintained.
If turning right when, it is possible to negate this overlap and leave an uncut
strip.
6) Improper cutting deck adjustment may produce a vacuum imbalance that, under
certain circumstances, could cause the air flow to push outwards from front
of the cutting deck. Most MTD deck designs are of "free floating"
design. Free floating decks should not have the anti-scalp wheels touching the
ground when the tractor is positioned on level surface. Free floating decks
should be adjusted so that the front deck lip is approximately 1/4"-3/8"
lower than the rear lip of the cutting deck. This relationship and adjustment
should be maintained throughout the cutting height adjustment range. If the
nose of the deck is higher than the rear of the deck improper air flow underneath
the deck may result. Improper vacuum underneath the deck can negate the necessary
"lift" needed to stand the grass blades erect for even cutting. If
the lawn has bare spots, or lacks a healthy lush character, this too can cause
vacuum leaks, especially pronounced in the higher cutting settings where the
grass blades are further spaced at the tips and vacuum leaks may become more
pronounced. Please consult the tractor Operators Manual for specific Deck Leveling
and Deck Engagement adjustments pertaining to a specific model tractor.
Problem: Discharged Grass is clumping
Solution: There are a few things that can cause clumping, clogging when bagging
or a poor mulching situation. Most of these are operational issues, although
some of them may have to do with the condition and type of cutting blade being
used.
Please review the information in the bulleted points below to help achieve improved
cutting performance and disposition of the grass clippings.
• CLEAN DECK? Make sure that the underside of your deck has been properly
cleaned of any debris or clippings. A clean cutting deck will provide the greatest
amount of air flow beneath and exiting from under the cutting deck. Sufficient
air flow is important for both discharging the clippings properly and/or mulching
the clippings.
• ENGINE AT FULL THROTTLE? It is necessary to run your unit at full throttle
during your entire operation. Lack of engine RPM and reduced blade rotational
speed can also result in reduced air flow underneath the cutting deck.
• GRASS TOO WET? Clumping can occur if you are mowing grass that is excessively
wet. Try to mow only when your lawn is dry. Note: Moisture makes up a significant
percentage of grass composition. Recent rains, foggy or damp conditions may
result in grass that may appear to be dry but actually is very moist. If the
mower wheels become obviously damp or wet when the mower travels across the
lawn, the lawn is too wet to move the clippings properly. Whenever possible,
allow adequate drying time, before mowing under these conditions.
• CUTTING OFF TOO MUCH GRASS? Poor grass clipping movement can occur if
you are mowing grass that is excessively long. Do not attempt to bag clippings
or mulch when cutting off more than 2" of the overall grass blades with
the mower. Overloading or "clogging" may occur if too much of the
grass being mowed is being forced through the discharge opening in the cutting
deck. If the lawn has been left to grow beyond normal cutting length, it may
be necessary to make repeat mowings, starting at a higher cutting height and
gradually lowering the cutting deck with each mowing pass until the grass is
returned to normal heights.
• TRAVELING TOO FAST? If operating at a faster ground speed, the mower
will have trouble trying to discharge this increased volume of clippings through
the grass collector chute properly. Make sure that you are traveling at a medium
to slow pace (keep the engine throttled up but either walk slower or shift to
a slower tractor speed) especially when bagging or mulching.
• BLADES DULL? An equipment issue that could cause this condition to occur
is if the blades themselves have not been sharpened and balanced recently. Properly
sharpened and balanced cutting blades will produce maximum air flow. Inspect,
sharpen and balance blades as needed.
• DO YOU NEED OPTIONAL HIGH LIFT BLADES? "High-Lift" design
cutting blades are designed to produce maximum ejection air flow out the deck
discharge opening and may be necessary when the grass type and/or bagging conditions
require additional exit airflow to eject the clippings completely. Generally
speaking, larger cutting decks manage more clippings and this increase of clippings
volume requires a greater amount of exit air flow to move the clippings out
from underneath the cutting deck without clumping.