Alamo MACHETE Product Service Manual page 158

POSSIBLE FAILURE / CAUSE & SOLUTION
Cylinder Won't Move Under Load:
CAUSE:
Piston has come off of Rod?
SOLUTION:
This can be difficult to find, If the Piston comes completely off of Rod it can be
pushed to bottom of Barrel below Port, Then Oil just circulates through Cylinder
with little or no resistance, This makes it appear there is no Pressure or valve isn't
working. The best way to check would be with a Flowmeter in Cylinder Line. Check,
Repair or Replace as required.
CAUSE:
Restrictor Valve Installed in Wrong Line, Backwards or Plugged?
SOLUTION:
Determine the correct location of installation for Restrictor and make sure it is in
correct location. Inspect for being Plugged, Clean or Replace as needed.
CAUSE:
Excessive Internal Leakage in Pump / Motor?
SOLUTION:
Perform Flow and Pressure Test. If results aren't within Specifications, determine
the cause of the internal leakage, correct the cause. Replace worn or damaged
parts. It is good to replace the Filter any time the Pump and/or Motor are repaired
or replaced. Pump and/or Motor wear usually occurs over a long period and are
gradual loses of power and excess heating of Oil. This may go un-noticed until it is
severe making the operator think it just started, this can make this type of failure hard
to determine. Pre-Mature Pump and/or Motor Failure wear occurs quickly, The
problem for these failures must be found and repaired or the failure will be repetitive.
The Most common cause of Pre-Mature Failure is Cavitation, Oil Contamination, Oil
Aeration and/or Defects in Pump and/or Motor. MACHETE SPECIFIC, When
performing the Flow Test on the Machete, The flow going to Motor and either the
return from the Motor or the Case drain must be determined. These figures will
indicate internal leakage in the Motor.
CAUSE:
Air in Oil?
SOLUTION:
Run the System for a few minutes. Check for Air in the Oil in the Tank. Air entrained
Oil will have a foamy appearance. If Air is present, find the Air Leak and correct it.
Air Leak can be in the Suction Line and Oil may not leak out because there may only
be Oil in that location when the Pump is sucking it in. With the Tractor Engine "Off"
you can find a leak by pressurizing the Tank; This will not take but a few pounds of
pressure (3 to 5 PSI or Less) look for leakage in the Suction Lines, Because the Oil
Pick-Up is lower than the Oil Level this will force Oil out the leak. Leaks in Hoses
and at Fittings can draw Air into System as Oil Flows Past. Systems that have had
severe or prolonged Air Entry Problems may have Experienced Pump Damage.
CAUSE:
Engine RPM Too Slow?
SOLUTION:
Run Tractor Engine at required Speed to achieve GPM through Pump, See
Specification Section in Repair Manual.
CAUSE:
Vent Plug Block or Not Installed? (Power One Way Cylinders)
SOLUTION:
This applies to Cylinders that only Stroke in or Out under pressure, The return
Stroke under gravity. Remove Plug, Clean or Replace as needed. If No Vent Plug
is there determine if one is needed and install as required. (See Parts / Operators
Manual for Vent Plug requirements).
Machete (Service Manual) 04/04
© 2004 Alamo Group Inc. 158
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