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Added 1-22-17

Mechanical Binding?

Mechanical Binding is mentioned (not using the term, but it is what it means) in the Meyer plow troubleshooting flow
chart. The problem is that unless something is bent or very "off" the plow will not bind when you PULL it side to side.

The troubleshooting flow chart for "Plow willl not angle left" says:

1. "Can the snow plow be angled by hand when the PA Rams are disconnected from the A Frame?"
2. "Will the snow plow angle right and left if not allowed to travel to extreme angle position?"
if YES
3. "Temporarily put 1/2" blocks between Sector andA Frame to limit the degree of angle. Will the snow plow now
4. "Weld 1-1/2" x 1-1/2" x 1/2" spacers to the A Frame stops."

The problem with 1 above is that we just couple the PA Rams together and see if we can move the plow by hand. This
is because once a plow is experiencing mechanical binding the bolts holding the PA Rams on are not likely coming out
without a cutting torch. So we pull the plow side to side. It is not the same as the PA Ram pushing in a specific place on
the Sector (the front bolt). So the result is the plow does not bind. Even if we cut the bolts off, and removed the PA
Rams, the plow will not bind. Again, because we are not pushing on that specific point to move the blade. The picture below is not perfect, or to scale but you get the idea.

Mechanical Binding - Snow Plow

However, as you pull and push the plow, IF you look at that specific point, you may notice the PA Ram going "over
center". In this case, when force is applied to the front bolt, the plow is trying to angle MORE to the side it is already
angled to. This is because the (angle of) PA Ram is over the center point, and it cannot extend more in the direction it is
trying to go. As you move the plow back and forth by hand, look at the King Bolt. IF it is rocking, spinning, or wobbling,
you likely have excessive wear to deal with. (Another indication is if you raise the plow, go to one end and push down on
the top of the plow, it will rock up and down a few inches, sometimes as much as 6").This can happen going right or left,
it is not specific to one side. Why does it happen?

snow plow rocks on ends

Geometry. The plow is designed to pivot back and forth on the King Bolt. The PA Rams extend and retract pivoting on
the front and back bolts. The back bolt holds the PA Ram to the A Frame, and the front bolt holds the PA Ram (live end)
to the Sector. The King Bolt passes through two holes in the Sector, and two holes in the A Frame. It is a "knife" hinge
essentially. When these holes (in the Sector and A Frame) get worn, and even egged out (oval shaped) instead of
round, this changes the geometry. Because in addition to pivoting at this point, the Sector can oscilate. This oscelation
allows the Sector to move in addition to just pivoting on the King Bolt, which in turn allows the live end of the PA Ram to
go over center. So once it is over center, it is tryingto angle MORE in the same direction as it extends instead of the
opposite direction. So the plow gets stuck to one side.

The fix is to remove the King Bolt (you will likely need a torch), and weld the 4 holes round again. HOW you weld them
round matters as well. IF you weld them wrong, in addition to not being able to get the bolt through the 4 holes, you can
change the geometry instead of putting it back to where it was designed to be. In the pictures below, the Sector is upside down.

Egged out hole in sector

Sector hole welded        Sector hole made round again

As you move the plow back and forth by hand, look at the King Bolt. IF it is rocking, spinning, or wobbling, you likely
have excessive wear to deal with. Another indication is if you raise the plow, go to one end and push down on the top
ofthe plow, it will rock up and down a few inches, sometimes as much as 6". Once a King Bolt has been beat on and hammered by being left loose for so long, you can rarely tighten it, or even loosen the nut without a torch.

As originally designed, the Sector rides under the "Sector Release Bracket" as it angles from side to side. When the
plow is straight, the Sector should be almost all the way under, touching the back of the Sector Release Bracket. If it is
more towards the front, or partially out from under the Sector Release Bracket, failure is close. In addition to the hole
being egged out, the hole in the top nosepiece is likely cracked and spread open. This is one way you can look at a
plow and know how hard it was used, the position of the Sector in relation to the Sector Release Bracket.

Sector Release Bracket on Meyer ST Plow

Back to "IF you weld them wrong".... The object is to put the Sector and A Frame Sector Release Bracket back to their
original position (Sector under the Sector Release Bracket). I added a "Reference Line" to illustrate what would happen
if you welded it wrong. You would move it more out from under the Sector Release Bracket.

Welding holes in Meyer ST Series plow Sector

The King Bolt is installed from the bottom up, that is correct. It will not magically fall out, the nylock nut will not let that
happen. Anyone who thinks theirs fell out, had sloppy holes in the Sector and A Frame and the bolt finally sheared.

You can install it from the top, but you will have to loosen ALL of the Trip Spring Eyes and tilt the plow forward. You will
have to do the same to remove or replace the King Bolt, after the Trip Spring Eyes have been rusting in place for years.
IF it is installed from the bottom, it can be replaced without loosening the Trip Spring Eyes.

The problem with the fix in the Meyer Troubleshooting (#4 above) is that yes, it will stop the plow from getting stuck, but
it will not fix the real problem, it will allow the holes to get worse until the plow breaks in two.

Plow broke in two

Here is a Meyer ST Series cracked Nosepiece, and the repair.

Cracked nosepiece

Nosepiece repaired

Here is another Nosepiece that was caught before catastrophic failure.

Hairline crack in worn nosepiece

How does the hole get egged out in the first place? - Post



Smith Brothers Services, LLC
3212 State Route 94
Suite 9
Franklin, NJ  07416
(973) 209-PLOW
We are open 9 - 5 Eastern Time M-F

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Author: Chuck Smith

Common Misspellings: Meyers, Mayer, Mayers, Myer, Myers, Maier, Maiers, Meijer.