SERVICE MANUAL
Paragraphs
1 8·22
H Y DROSTATIC STEERING SYSTEM
This section covers the steering system
used on MF235 Orchard models and all
MF245 models except Vineyard.
LUBRICATION AND BLEEDING
All
Models So Equipped
18. The hydrostatic steering hand
pump and steering cylinder assembly
are lubncated by the operating fluid.
Massey-Ferguson Permatran
m
Oil is
recommended. The system is self
bleeding, but steering should be cycled
and reservoir refilled as often as
necessary until level stops dropping.
SYSTEM OPERATING PRESSURE
AND RELIEF VALVE
All
Models So Equipped
19. Normal system relief valve
pressure is approximately 8300 kPa
(1200 psi) with engine operating at 2000
rpm. Refer
to
paragraph
7
for testing and
adjust.i ng procedures.
STEERING CYLINDER
All Models So Equipped
20.
OVERHAUL. Two
types
of
steer
ing cylinders have been used. l f
two
Fig. 23-Exploded view of
one type of steering cylinder
used on Models MF23S and
MF245
equipped
with
hydrostatic steering system.
Refer to Fig. 22 for other type
cylinder and legend.
steering cylinders
are
used on the same
tractor (Orchard models), both cylinders
should
be
alike.
'lb
disassemble the cylinder shown in
Fig. 22 or 23, remove oil from cylinder
by working piston back and forth.
Remove
rod
end
(1)
and star washer, then
unscrew cap
(7).
Renew all seals when
assembling. Heat Teflon rings in warm
oil to soften before installing. Install
piston in inner
tube (6)
from end opposite
hole {H-Fig. 23). Do not push piston and
seal ring past the hole. Lip of scraper
(9-Fig. 22 or 23) should be out. Lubri
cate all parts before assembling. Tighten
cap
(7)
to approximately 400 N
·
m (300
ft.-lbs.) torque.
Fig. 22-Exploded view of
one type of steering cylinder
used
on
Models MF235 end
MF245
equipped
with
hydrostatic steering system.
Refer to Fig. 23 for other
type
cylinder.
I Ball )Om�
�nd
2.
Cyhnd�r
borrel
3 Rod &
p111.0n
4. "0
..
r�nN
6
Seal
ring
6
Inner
tub<>
7
End cap
8 Seal
9
Scroper
10 Seal
r�njl
HYDROSTATIC HAND PUMP
All
Models So Equipped
21.
REMOVE AND REINSTALL. 1b
remove the hydrostatic hand pump, first
remove the battery and the steering
wheel. Disconnect. the oil pressure line
at gage and tachometer cable at both
ends, then remove the tachometer cable
and cable housing. Mark all wires to
facilitate reassembly, then disconnect all
wires from instrument panel gages.
Remove lights from panel gages and
disconnect fuel shut-ofT from inject1on
pump (diesel models). Remove the com
plete instrument panel with gages.
Disconnect wires from starter switch
and light switch, then unbolt and
remove the rear hood assembly wilh
starter and light switches mstalled.
Disconnect linkage from both ends
of
the
throttle cross shall., lhen slide shaft. from
left side of tractor. Remove the complete
air cleaner assembly and the battery
platform. Clean the area thoroughly
before disconnecting any
powe1·
steenng
lines. Disconnect the four hydraulic lines
and plug all openings to prevent en
trance of d1rt, then unbolt and remove
the hydrostatic hand pump.
'lb
reinstall, reverse the removal pro
cedure. Be careful to connect
wires
to in
struments conectly. Bleed the hydraulic
system as outlined in paragraph
6 aner
all lines are connected. Be sure that
system is not allowed to operate without
fluid in reservoir.
Orchard Models
22.
OVERHAUL.
MF235 and MF245
Orchard models are
e
qui
p
ped with a
Char-Lynn open center type hydrostatic
hand pump. The rotary valve sleeve
15