Likely the deck hangers are bent. I'd guess when you hit that "twig"
(that stopped the mower and bent the deck into the blade) it shoved the
entire deck back and bent some stuff.
I have to take issue with your original description of events. It just
doesn't ring entirely true. The stick you showed could not have caused
the damage you described. At worst it would have jammed between the
blade tip and deck, bend the blade, and caused everything to stop, maybe
even break a belt. But the fact that the blade cut into the deck means
that the deck was pushed (read bent) into the path of the blade. That
takes a pretty substantial amount of force. You said the engine also
stopped which makes me think that whatever you hit was large enough to
stop the forward motion of the tractor. Maybe a stump or some other
Was Kathy using it when it happened or were you?
I was on the mower, what happened was the blade hit the stick the stick then
like catapulted the blade into the mower deck (this deck is one of the fancy
high output types so the deck is not flat but dips from the top down towards
the discharge) so the blade hits the deck cuts into the deck about 2 1/2
inches and that is when everything stopped.
I never hit anything that would have bent anything like hangers which in my
case would be beneficial because the mower is advertised to have a 4 inch
cut and is only slightly less than 3 1/2 inches, and that's without my fat
ass on it. gotta be nearer 3 when I'm on, (I weight 185)
I have seen a lot of bent blades but I've never seen one that was bent
such that it stretched and sliced into the deck.
Let's just say it is a 20" blade. That is 10" from the center bolt or
it's pivot point to the tip. The deck will be approximately 10-1/4"
minimum distance from that same point. It is physically impossible to
bend a blade (by hitting a stick of any size) in such a way that it
becomes longer. The deck *must* be bent for that to happen. Either the
spindle mounting point was twisted causing the blade pivot point to move
or the edge of the deck was pushed into the path of the blade. Either
way that would take a pretty substantial amount of force and more than
the stick you describe could possibly be responsible for.
ok Art, you have compelled me to tell my deck wreck story.
it all happened when I was mowing over a location where I
knew a sweet gum root was sticking up higher than cutting
level 3 and I forgot to raise the deck to cutting level 4.
the deck itself hit the root with sufficient force driving
the deck back into the blade on the right side. the blade
actually sliced into the deck and cut in a downward
direction for about one inch. the blade did not bend the
portion of the deck where the blade pivot point,
referred to as the spindle, bent.
the PTO belt got a flat spot burned on it before I was able
to disengage the PTO. lots of stinky white smoke was all I
got for my ruined belt. the flat spot was sufficient to
force the discarding of the belt since it produced the out
of balance thumping that will lead to a ruined oil seal on
the PTO shaft extending from the bottom of the 22hp motor
where the PTO belt runs on it's pulley.
at this point I was thoroughly pissed off with myself since
it had only been about 2 weeks prior I'd had to do major
repairs as a result of the big down hill ditch wreck. I
decided to work off the hostilities by attacking the sweet
gum root. I felt better after that sweet gum root was
declared to be no more.
the next day I removed the deck, stripped it down and
reintroduced it to the 10 pound maul the anvil the torch and
the welder. I could almost hear the deck saying "oh shit not
again." after enjoying a nice day in my workshop and some
really good coffee the deck was restored to it's correct shape
with the addition of some new reinforcing structural stabilizers.
the repair worked out well and now when I go over the spot where
the sweet gum root used to be, I just smile.
ps: I feel sorry for people who have to call for help and then
wait for someone to show up with their name written on their shirt.
Here in the glacial carved Hudson Valley, we have buried rocks the size
of Volkswagens. You cannot dig a hole more than a foot deep without
hitting a rock which may be from the size of a football up to the
I have been scalping rocks and tree branches, with my cheap Murray
tractor and mower deck, that are much bigger than the OP's bout with a
twig. I have never bent a blade so much as to even scrape the sides or
top of the metal mower deck. When I do my annual sharpening, I may have
to straighten a blade a little with my hammer and vise anvil.
If I had happen what the OP experienced, I would have bought, borrowed,
or stolen a truck, to bring it right back to Sears, drive it inside and
left it on the floor if they didn't get me a new one.
now that's the attitude I can admire, appreciate and respect.
if you ever need someone to hold the door open while you're
driving one back inside, you just let me know.. the visual
of those sears customers scurrying for their safety puts a
big grin on my wide eyed country boy face.
Sorry Art this deck is not like other decks, I know exactly what your
talking about, but this deck dips down at the discharge (behind it), I
guess it's some kinda aerodynamic thing,
If you want I can post a link to a picture.
Actually, it is like all other mower decks. The back of the deck is set
at the depth desired and the front is a little higher. The idea is that
the mower deck cuts twice. The front of the blades make the first cut
higher than the depth setting and the trailing edge makes the second cut
to the depth desired.
Instead of leaving long blades of cut grass, there will be shorter pieces.
I take great care leveling my decks. If the front lip seems high, it
merely eases movement into the swath. Blades tilted up enough to make a
difference regarding grass height/blade length would be noticeable in
the finished lawn.
The effect you mention (usually on high-end mowers/blades) can be
achieved with a blade that looks as if the first inch or two has been
twisted up; edge on the blade looks (or doesn't look) like this:
Lawns around Lake Sam Rayburn are very sandy, tending to erode the tips
of blades. When eroded past their useful life, they leave a slight
ridge with twin blade decks and two ridges with triples. Blades tilted
up would tend to do the same.
One of my lawn tractors, a twin blade 40" Murray, suffered my backing
over a thick door mat. (Hemp, I do believe.) After trying to get the
kink out of the blades, I replaced them, but couldn't get the ever so
slight warp out of the deck. As long as I used a 1/4" spacer on the
left side of the deck when leveling, it cut perfectly. Otherwise, the
lawn looked like I cut it with a low tire.
Tires are another thing. At 8 or 10 psi, most gauges aren't accurate
enough to get tires exactly the same pressure. Turf tires can vary,too.
The best way to adjust tire pressure is with a tape measure or length
of string marked with the front and rear circumference of the tires.
Simply loop the tape or string around the tire and adjust the air
pressure till both sides are equal. It might surprise you that the
actual pressure might differ from left to right. As long as the
circumference is equal, you will be level. (Measure twice, bleed once.)
I may be wrong on these points, but they have served me well. I've been
cutting St Augustine since nineteen and fifty somethin'.
Any are welcomed (and encouraged) to disagree (except the mean ol' trolls).
No, you have that backwards. The blade is tipped ever so slightly
forward to cause the front edge to be just slightly lower. This greatly
increases the vacuum and it it lowers the drag on the blade.
But I agree that his deck is like others. Basic deck design pretty much
the same across the board. The deck will dip down behind the discharge.
That is what "encourages" the air and grass to leave through the
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