Alamo MACHETE FC-0002 - Manual (Page 168)

MAINTENANCE
MACHETE BOOM 3/09 Maintenance Section 4-22
©2009 Alamo Group Inc.
MAINTENANCE
The cutter shaft will run out of balance if:
1. Wire, rope, string, rags, etc., around the cutter shaft, are holding the knives in a folded back position.
Remove such foreign objects and be sure all knives are free to swing to the extended position.
2. Knives are missing or broken. Replace missing or broken knives.
3. Knife hanger lugs are broken off shaft. This condition usually results from continued operation in con-
tact with large hard objects where the knife hanger lugs themselves are hitting the hard objects. Lugs
should be replaced using arc welding equipment so as not to direct too much heat in one area of the
shaft.
4. Cutter shaft ball bearings are worn enough to have radial "play" in them. Replace ball bearing and
other worn parts to eliminate "play".
5. Shaft is bent. The shafts are straight within a couple of thousandths of an inch when they are made. It
is possible that they will become bent in use, such as if the shaft is hooked on a stump while the tractor
is moving forward at a good speed.
6. Shafts are operated at improper speed. Rotating shafts have what is known as a natural period of
vibration. The same is true of the cutter shafts on the Flail Mowers.
The actual speed at which the harmonic will occur will vary with each mower and each installation. To avoid
this harmonic vibration when operating the mower, it may be necessary to adjust the engine speed of the
tractor up or down.
Some units have a harmonic vibration which occurs below the nominal operating speed. On these units, it will
be noticed that there is always a little vibration at a particular PTO engine speed as the mower is being sped up
to operating speed. This occurs as the shaft passes through its normal harmonic vibration point. As long as
the mower is opened at the proper speed, then harmonic vibration will not be an issue .
Be certain to clamp or securely support the Spindle Housing and sub-assemblies to prevent
injuries to hands and feet due to inadvertent dropping or falling over.
Always wear safety glasses and gloves to prevent eye and hand injury when chiseling or
hammering on metal components. Hardened metal will chip un-expected.
An assembled spindle housing is quite heavy. Use a hoist or get help to handle them safely.
Lift carefully and properly using your legs to lift - NOT YOUR BACK.