Jacobsen SXG323, Service Manual

Page: 115 / 230

SERVICE MANUAL FOR SXG323&326
114
acceralate to the specified speed.
(2) OIL TEMPERATURE
It is a very important factor at what temperature
a hydraulic system operates. High operating tem-
peraure will cause working oil to deteriorate
faster, that is, oil is oxidized faster. On the other
hand excessively low operating temperature in-
creases oil viscosity resulting in poor mechani-
cal efficiency of the HST.
Consequently abide by the following items:
a. When starting the machine at 10
°C
or colder
temperature, wait until oil temperature becomes
higher than 10
°C
by warm-up operation or us-
ing an oil heater. Then start operation.
b. Normal operating temperature: 20
°C
to 60
°C
c. Maximum operating temperature
The maximum operating temperature should be
80
°C
. This limit is determined form the viscoci-
ty, oxidation-proof property of working oil and
deterioration of O-rings and oil seals.
Consequently operation at higher than 80
°C
will
shorten the service life of the HST and working
oil.
(3) PERIODICAL INSPECTION AND CHANG-
ING INTERVALS OF WORKING OIL
As the system operates, deposits like sludge ac-
cumulate within circuits and oil tank and work-
ing oil deteriorates, which will prevent the sys-
tem from smooth operation in the end.
Consequently working oil should be checked
periodically to replace it timely with new one.
As it is very difficult to judge how oil has dete-
riorated visually, a rule of thumb is given below.
Normally the oil should be replaced after the
intial 50 hours of operaton and then every year
(before the new season begins) when the
machine is used for less than 250 hours or every
250 hours of operation.
As water and sludge will be deposited in the cir-
cuits and oil tank when replacing the working
oil, the whole system should be flushed clean
before filling it with new oil
5. ADJUSTMENT OF HIST
Warning:
After a long time of use, the neutral position of
the HST unit can shift, which will cause various
troubles such as difficulty in stopping the lawn
mower, changing over between forward travel
and reverse travel, etc., which is very dangerous.
Important:
• When the HST unit is out of order, ask your deal-
ers to repair it.
• The adjustment of the neutral position of the HST
unit should be done by your dealers.
When there is no alternative but for the user to adjust
it, follow the next instructions:
The neutral arm of the HST unit is located around
the centre under the step.
With this arm the neutral position can be adjusted.
Fig. 10-45 (1) Lawn mower (3) Front wheel
(2) Tyre chocks (4) Rear wheel
a. Place the lawn mower on level, hard ground Put
tyre chocks in the positions a little apart from the
front wheels and rear wheels as shown in the fig-
ure.
b. Shift the PTO lever to the OFF position (
N
).
c. Stop the engine and remove the starter key.
d. Apply the parking brakes (UGE) or locking brake
(UE).
e. Loosen the lock nut of the adjust rod.