Dongfeng DFA1101GZ5AD6J-907. Manual - part 17

General Adjustment 

9—3

Note:
Open the cap of radiator while the engine is        

hot, be sure to turn the radiator cap slowly to low          
pressure position to reduce the inner pressure      
to avoid the hurt by the hot water injection. 

Check the Opening Temperature 

of the Thermostat

Check the thermostat working 

 

 

condition in hot water while perform the      
48,000km maintenance.

The opening temperature of the    

thermostat is 76 ℃ and 86 ℃

The full opening stroke of the     

thermostat:  not  less  than  6mm    
(3~5min, in boiling water).

Note:
The thermostat is necessary for engine to      

keep normal working, so it can not be removed        
arbitrarily.

Adjustment of Fan Belt

The tightness of fan belt should be      

checked frequently. The  checking   
method is like this, press  the  belt  at  a        
force of 29~39N  to  see  whether     
deflection is in the range of 10~15mm      
(Note:  Both belts should meet the     
requirement). Over tighten will damage    
the bearing of water pump and the      
bearing of generator,  over  loosen  will     
cause the belt slipping,  low  cooling     
efficiency and engine over heating.

Chang the relative position of 

 

 

 

adjusting arm to the generator to adjust      
the tightness of fan belt.

General Adjustment

9—4

Pump Fuel Manually and Bleed 

Air Out of Fuel Supply System

1.Bleed screw
2.Handle screw cap
3.Drain plug

Loosen the bleed screw (1) on the      

injection pump and the screw located     
above the diesel filter,  and screw out      
the handle screw cap (2) of fuel supply       
pump, take out the handle up and down       
till the there is no bubble in the flowing        
fuel out from the screw, then tighten the       
screw and the handle screw cap.

Water-leak Hole of the Water 

Pump

The water-leak hole under water    

pump  body  is  used  to  leak  the  water       
from the water seal,  so  keep  the  hole       
not being blocked is very important,     
thus the water will not be remained      
inside the water pump cavity to 

 

 

 

 

damage the bearing lubrication.

If  the  water  leaks  a  lot  from  the       

hole while parking, dismantle the water     
pump for repairing.

Air Valve Clearance Adjustment

1.Camshaft gear
2.Timing of pin
3.Gear case cover

Check  and  adjust  the  air  valve     

clearance every 12,000km, and the    
normal clearance is(under cold 

 

 

condition):

Inlet valve: 0.25mm
Exhaust valve: 0.50mm
No matter the clearance is too     

large  or  too  small  are  harmful  to  the       
engine. If you find the noise of the air        
valve is too loud during using, you must       
adjust it in time.The air valve clearance      

General Adjustment 

9—5

adjustment should be done under the     
cold engine.
Adjusting method:

1.Remove the air valve cover.

2.Press the timing pin of the engine(on      
the timing gear chamber close to fuel      
injecting pump), and use a wrench to      
turn the engine slowly until the timing      
pin is inserted into the timing hole of the        
camshaft gear and the 1st cylinder is in       
the compressed top dead center.

3.During this time, you must adjust the      
following air valve clearance(counted   
from the front to the end): valve 1(inlet),       
2 (exhaust), 3 (inlet), 6 (exhaust).

4.After the adjustment, make marks on     
the pulley and the timing gear chamber,      
then turn the engine to align the marks.

5.Then adjust the following air valve     
clearance: 4 (exhaust), 5 (inlet), 7 

 

 

 

 

(inlet), 8 (exhaust).

Note:
When you have found the top dead center       

of the 1st cylinder, you must first drop out the         
timing pin then you can adjust the air valve        
clearance.

Adjustement of Clutch

The clutch is controlled by 

 

 

 

hydraulic mechanism,  the  adjustment   
method for the total  travel  and  free      
travel of the pedal is as below:

1.Adjust the clearance between the    
push rod and the piston of master      

General Adjustment

9—6

cylinder to 0.2~0.7mm. When made the     
adjustment,  loosen the lock nut and     
turn the push rod towards the piston,      
when the push rod touch the piston,      
withdraw the push rod by 1/7~1/2 pitch,      
then tighten the lock nut. 

2.Adjust the free travel of slave cylinder      
push rod to 3~5mm and tighten the lock       
nut. 

3.After the above adjustments has    
finished,  the travel of master cylinder     
push rod and slave cylinder push rod      
should be 20~24mm,  and 17~20mm,    
the free travel of clutch pedal should be       
30~40mm.

Air Release of Clutch

The existence  of  air  in  clutch     

hydraulic system may lead to abnormal     
work  for  clutch  control  system,    
therefore it is necessary to release air.      
The method is like this:

1.Fill  up  the  clutch  oil  reservoir  with      
composite brake liquid,  and  make  the     
air pressure of the air tank reached to       
650kPa.

2.First remove  the  dust  cap  of  clutch      
slave cylinder, and loosen  its  bleeding     
bolt, then engage a matchable hose to      
bleeding  bolt  at  one  end  and  put  the       
other end into a bottle filled with brake       
fluid, and then trample the clutch pedal      
repeatedly until some air bubbles come     
out.