TROUBLE SHOOTING CHART
(VTM42 STEERING PUMP)
TROUBLE
PROBABLE CAUSE
REMEDY
Pump Not Delivering Oil.
Driven in wrong direction of
Check direction of pump shaft rotation. It should rotate
rotation.
clockwise as viewed from the coupling end of the unit.
See also reassembly instructions for pump cartridge.
Pump drive shaft
Remove pump. Determine damage to cartridge parts (see
disengaged or sheared.
disassembly instructions). Replace sheared shaft and
needed parts.
Flow control valve stuck
Disassemble pump and wash control valve in a clean
open.
solvent. Return valves to its bore and slide it back and forth.
No stickiness in movement should occur. If a gritty feeling is
noted on the valve O.D. it may be polished with a crocus
cloth. Avoid removal of excess material or rounding of valve
edges during this operation. Do not attempt to polish the
valve bore. Wash all parts before reassembly of pump. Fill
system with clean oil as recommended.
Vane or Vanes stick in slots.
Disassemble pump. Examine rotor slots for dirt, grime or
small metal chips. Clean rotor and vanes in a good grade
solvent (mineral oil or kerosene). Reassemble parts and
check for free vane movement.
Oil viscosity too heavy to
Use fluid of the proper viscosity as recommended in oil data
pick up prime.
(Table).
Noisy Pump Operation.
Pump intake partially
Drain system completely. Flush to clear pump passages.
blocked.
Flush and refill system with clean oil as recommended.
Air vent for oil tank clogged
Remove filler cap and clean air vent slot. Check strainer in
or dirty strainer.
tank for clogged condition. Drain, flush and add clean oil to
system.
Air being drawn into pump
Pump must receive air-free oil or pump will be noisy. Drain
return connection.
system. Tighten all hose connections. Clean or replace
filter. Add clean oil as recommended.
Leaky shaft seal.
Check pump shaft seal and replace if sealing lip has been
damaged. Check for scoring of shaft at seal contact area.
Replace faulty shaft.
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