CG938H Wheel Loader. Manual - part 17

 

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Steering is 
normal in 
slow 
turning and 
heavy in 
fast turning 

Steering is normal in slow 
turning and heavy in fast 
turning 

(1). Insufficient oil supply 
from oil pump 
(2). Large pressure loss 
between priority valve and 
steering gear 
(3). Priority valve plug 
blocked 
(4). Air in control oil circuit 
between priority valve and 
steering gear 

(1). Repair or replace oil 
pump 
(2). Use a priority 
control spring with larger 
control pressure, or 
redesign pipeline with an 
externally controlled 
priority valve 
(3). Turn steering wheel 
to reach dead end and 
then keep turning to 
open steering safety 
valve for air elimination 

Irregular 
noise and 
bubbles in 
oil 

Irregular noise and bubbles 
in oil, intermittent working 
of cylinder in steering 

Air in steering system 

(1). Check oil level and 
add oil to oil tank 
(2). Check air intake 
pipeline for air leakage 
and repair 
(3). Eliminate air in 
steering system 

6. Cooling fan control system 

I. Structure and operating principle of cooling fan control system 

1. Diagram of cooling fan control system 

 

 

 

 

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(1). Pressure tap: measures motor inlet pressure, (2). Hydraulic motor: 

WM09A1C230R07TB122HGNNR2320001M, (3). Overflow valve: provided with hydraulic motor, 

(4). Motor support assembly, (5). fluid coupler 

2. CG938H loader adopts an independent cooling system (cooling fan control system) mainly 

consisting of motor, motor support assembly, coupling flange, fluid coupler, etc., system cleanliness 

is controlled within Grade NAS1683 9. 

Features of cooling fan control system: 

(1). Better cooling effects on hydraulic oil and torque converting oil; 

(2). Cooling effects on hydraulic oil and torque converting oil are not affected even under loaded 

working conditions of the loader. 

System cleanliness is controlled within Grade NAS1683 9. 

II. Motor: WM09A1C230R07TB122HGNNR2320001M manufactured by Haldex International 

Trade (shanghai)  Ltd.

 

Position of motor 

 

 

 

 

 

 

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IMPORTANT 

 

Discounting and servicing of motor by untrained maintenance staff is strictly prohibited. 

 

CAUTION 

 

When replacing rubber tube assembly in motor, loader engine should be shut off first to 

release pressure and cool down hydraulic oil (to a safe degree) before the replacement is made. 

IV. Safety marks 

All safety marks and meanings thereof for cooling fan control units will be described here. 

Operators must read carefully and understand completely these descriptions, which should be 

complied with in operation and maintenance. If any mark is damaged, lost or illegible, replace 

it with a new one. 

 

 

   

 

 

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II  Cab Facilities 

2.1 

Instrument Desk and Accessories 

 

 

1. 

    Engine failure signal light 

2. 

  Working rotation indicator 

3. 

  Emergency warning light 

4. 

  Emergency steering signal light