HY13-1527-M1/US
Torqmotor™ Service Procedure
TF, TG, TH and TL Series
Parker Hannifin Corporation
Hydraulic Pump/Motor Division
Greeneville, TN 37745 US
6
NOTE: Before troubleshooting any system problem, check service literature published by the equipment and/or
component manufacturers. Follow their instructions, if given, for checking any component other than the Torq-
motor™ unit.
Preparation
Make your troubleshooting easier by preparing as fol-
lows:
• work in a clean, well-lighted place;
• have proper tools and materials nearby;
• have an adequate supply of clean petroleum-based
solvent.
WARNING: SINCE SOLVENTS ARE FLAMMABLE, BE
EXTREMELY CAREFUL WHEN USING ANY SOL-
VENT, EVEN A SMALL EXPLOSION OR FIRE COULD
CAUSE INJURY OR DEATH.
WARNING: WEAR EYE PROTECTION AND BE SURE
TO COMPLY WITH OSHA AND OTHER MAXIMUM
AIR PRESSURE REQUIREMENTS.
Preliminary Checks
Hydraulic systems are often trouble-free. Hence, the
problem an operator complains of could be cause by
something other than the hydraulic components.
Thus, once you have determined that a problem ex-
ists, start with the easy-to-check items, such as:
• parts damaged from impact that were not properly
repaired, or that should have been replaced; and
• improper replacement parts used in previous
servicing
• mechanical linkage problems such as binding,
broken, or loose parts or slipping belts
Hydraulic Components
If you think the problem is caused by a hydraulic com-
ponent, start by checking the easy-to-reach items.
Check all hoses and lines for cracks, hardening, or
other signs of wear. Reroute any usable hoses that are
kinked, severely bent, or that rest against hot engine
parts. Look for leaks, especially at couplings and
fittings. Replace any hoses or lines that don’t meet
system flow and pressure ratings.
Next, go to the reservoir and filter or filters. Check
fluid level and look for air bubbles. Check the filter(s).
A filter with a maximum 40 micron filtration is recom-
mended for the Torqmotor™ system.
Visually check other components to see if they are
loosely mounted, show signs of leaks, or other dam-
age or wear.
Excessive heat in a hydraulic system can create prob-
lems that can easily be overlooked. Every system has
its limitation for the maximum amount of temperature.
After the temperature is attained and passed, the fol-
lowing can occur:
• oil seal leaks
• loss of efficiency such as speed and torque
• pump loss of efficiency
• pump failure
• hoses become hard and brittle
• hose failure
A normal temperature range means an efficient
hydraulic system. Consult the manuals published
by equipment and/or component manufacturers for
maximum allowable temperature and hydraulic tests
that may be necessary to run on the performance of
the hydraulic components. The Torqmotor™ is not
recommended for hydraulic systems with maximum
temperatures above 200°F (93.3°C).
Troubleshooting Guide
