TYM T303HST User Manual

7.Mark the forward and reverse relief valves and
their ports to ensure they go into the correct holes
during assembly.Remove the relief valves from
the back plate.Clean the relief valves in a suitable
solvent,and check for damaged springs or seats.
NOTE: The relief valves are dual purpose valves.
Each valve contains two springs.A weak spring
(check valve when other circuit is in use) and a
strong spring(6000psi relief valve).Valves can not
be adjusted,and there is no serviceable parts inside.
If any malfunction is suspected,replace the relief
valve.
8.Examine the relief valve faces,and the seats in the
IMPORTANT:To avoid damage to needle bearings
When removing or installing,press only against
side of bearing with lettering.
When removing bearings from the back plate,be
Extremely careful to not damage machined surfaces.
10.Inspect pump side needle bearing.Bearing
should spin freely,and needles should not fall out
of bearing cage.If replacement is necessary,
press bearing out from the motor side of the
housing.
11.On the motor side of the back plate,remove the
cooler bypass valve and check for damage or
debris in spring or seating areas.Clean or
replace parts as required.
Valve face
Relief Valve
O-ring
Relief Valve spring
Valve face
Cooler bypass valve
Plug
Filter bypass valve
Needle bearing
8.Examine the relief valve faces,and the seats in the
back plate.The faces of the check valve and the
seats in the back plate should be free of burns and
defects.
IMPORTANT:Damage to pump may occur if charge
pressure relief valve and cooler bypass valve
springs are accidentally swapped.Keep
valves and springs separated or label them to
prevent mix-up.
9.Remove the charge pressure relief valve and check
for damage or debris in spring or seating areas.
Clean or replace parts as required.
replace parts as required.
12.Remove the filter bypass valve and check for
damage or debris in spring or seating areas.
Clean or replace parts as required.
13.Inspect the motor side needle bearing.Bearing
should spin freely,and needles should not fall out
of bearing cage. If replacement in necessary,
remove using a suitable blind hole puller.
14.Remove three plugs from pump side,and one
plug from motor side of back plate, and clean
out oil passages using a suitable solvent and
compressed air.
4-25
Charge pressure
relief valve
Plugs

TYM T303HST Specifications

General

Brand	TYM
Model	T303HST
Category	Tractor
Language	English