Service Manual

Topdresser 1800 & 2500 Hydraulic SystemPage 3 – 21
Procedure for Charge Pressure Test
:
1. Make sure hydraulic oil is at normal operating tem-
perature by operating the machine for approximately 10
minutes.
2. Park machine on a level surface. Make sure tow ve-
hicle engine is off and that the parking brake is applied.
3. Read and follow Precautions for Hydraulic Testing.
IMPORTANT: Make sure to thoroughly clean around
all hydraulic connections that will be disassembled.
4. Locate and remove plug from the P2 port on the hy-
draulic control manifold (Figs. 14 and 15).
5. Connect pressure gauge with a hydraulic hose at-
tached to the P2 port on the hydraulic control manifold.
Make sure hose is long enough so the operator can read
the gauge while driving the tow vehicle.
6. Start engine on tow vehicle and tow the Topdresser
at a minimum of 3 MPH. Leave the Topdresser control
handle switch in the OFF position.
7. The pressure gauge will display system charge pres-
sure and should read at least 50 PSI (3.4 bar). Record
test results.
8. Stop tow vehicle, shut off engine and record test re-
sults.
9. If charge pressure specification is not met, inspect,
repair or replace charge relief valve (R2) in hydraulic
control manifold. Also, consider a clogged oil filter, air in
the hydraulic system or a worn charge motor/pump.
10.Remove pressure gauge from hydraulic manifold
and install plug into manifold port P2. Torque plug 19 ft–
lb (25.7 N–m).
11. After testing is completed, make sure hydraulic tank
is full.
1. Hydraulic manifold
2. P2 port
3. Charge relief valve R2
Figure 14
1
2
HYDRAULIC MANIFOLD FROM MACHINE
WITH SERIAL NUMBER BELOW 240000000
3
FRONT
1. Hydraulic manifold
2. P2 port
3. Charge relief valve R2
Figure 15
1
2
HYDRAULIC MANIFOLD FROM MACHINE
WITH SERIAL NUMBER ABOVE 240000000
3
FRONT
Hydraulic
System