1. Motor Starting Failure or Motor Stops Running When in Motion

 Possible Causes

 Solution

a.    no-fuse breaker kicks back

a.    check wires connected to power source to make sure no short-circuit happens， make sure terminals are fastened  properly .

b.   overload protector kicks back

b.   1) make sure amperage preset on      overload protector is correct--3   ampere / 1HP  for380V 3Ph.                                                                      

2) be sure that working pressure doesn´t exceed limited range.                                                                                                  3) make sure unloading pressure  preset on low-pressure pump is proper as specified,  after above examinations are done well, switch on overload protector.

c.    burned fuse

c.       before replace fuse, make sure    footswitch wires and parts on power  control box are not damaged     

2.  Motionless Ram or Ram with No Working Pressure

 Possible Causes

 Solution

a. working pressure preset by pressure  regulator too low 

a. increase working pressure

b. opposite motor turning direction

b.exchange connection one another  of any two of  the three wires ,connected to power source.

c. damaged connector between motor and oil pump

c.replace connector or contact rubber with new one.

d. insufficient hydraulic circulation oil

d. refill oil tank to approx. 80% of total volume

e. loosened inlet / outlet joint of hoseof oil pump, or broken hose         

e. fasten loosened joints or replace hose with new one

f.  inoperative direction-control ( it may be caused by burned solenoid coil or blocked valve spool or    hydraulic system )

f.   refer to hydraulic circuit to check solenoid action. Clean up blocked valve spool or replace solenoid coil with new one

g. improper single preset on stroke   control set

g. clean up dirt and impurity from the   device

 h. improper connection of footswitch /     push button wires or bad contact

h.   adjust them properly or replace defective wires with new ones

3.  Abnormal Movement of Ram

 Possible Causes

 Solution

a. ram with no speed-change      movement

a. 1) re-preset speed-change point on stroke control set.               2) if wires for speed-change switch  break, cut off damaged part and connect the wire again .  

b. Ram with on fast-approach movement ( it is usually caused by guide block and slider block contacting too closely )

b. adjust guide device

c.  inoperative direction-control valve

c.    refer to hydraulic circuit to check solenoid action and solenoid coil 

d. damaged stroke control set or with bad contact     

d. replace it with new one

4.  Working Pressure Insufficient

 Possible Causes

 Solution

a. defective pressure regulator

a. check every part of it and be sure nothing blocks them up

b. loosened joint of hose of oil pump

b. fasten it properly

c.  unclosed pressure relief valve, logic valve or prefill valve ( which may   be caused by blocked valve spools )

c. wash blocked valve spools completely 

d. low viscosity machine oil or high oil temperature   

d.   select correct hydraulic circulation oil as specified oil temperature must not exceed 70℃

e. worn-out oil pump

e. replace it with new one

f.   worn-out oil pump packing

f.  replace it with new one

5. Abnormal Noise

 Possible Causes

 Solution

a. worn-out connector / contact     rubber between motor and oil pump

a. check clearance of connector, if  rubber is worn out, replace it with  new one.

b. blocked filter on oil tank outlet

b. clean and wash filter

c.  oil pump hose inhaling air

c.  be sure to make oil level overreach  filter fasten side joint of oil pump hose 

d. bad connection between motor and  oil pump    

d. be sure to posit motor and pump in  line with same circle center

6.  Cylinder / Hydraulic Manifold Leakage

 Possible Causes

 Solution

a. loosened oil relief valve or socket screws on cylinder flange

a.   examine o-right inside flange, fasten socket screws.

b. overtight or loosened joints on     hydraulic system

b.   fasten loosened joints or replace joint sleeves with new ones

c. worn-out o-right or missing

c.   replace it with new one

d. improper cylinder cover and packing  installation

d.   adjust it properly

e. damaged or worn-out u-packing 

e.   replace it with new one

7.  Slow Ram / Cylinder Movement

 Possible Causes

 Solution

a.   insufficient machine oil

a.  refill oil tank to approx. 80% of  total volume

b. blocked filter on oil tank outlet

b.  clean it

c.   high machine oil viscosity or low oil temperature

c.  select machine oil as specified

d. unclosed valve spools cause partly oil return to oil tank 

d.  wash blocked valve spools