Waterjet High pressure pump trouble shooting

Trouble Shooting

No Pressure

Normal shifting

a. Check if water pump is working normally

b. Check water supply to see if enough pressure

c. Check if need to replace orifice or water jet not focused

d. Check end bell to see if there is leak of oil or water. If leak water, It is time to replace the HP seal. If leak oil, need to change the LP seal.

e. Check if inlet check valve working properly. If not working, water will return to the low pressure side.

f. Check if outlet check valve is working properly, touch with hand to see if it is hot .

g. Check HP plunger. Remove inlet/outlet check valve, Turn on the oil pump, observe if the plunger is shifting normally.

Shifting slowly or no shifting

a. If not shifting and oil pressure is high, remove the wire connection on the side of the directional valve and use your finger to push either side.

b. Adjust the position of the Hall switch. 

c. Check if the Hall switch and the connected relays

d. Check oil valve and related electrical circuit including relays.

e. Check if the oil flow rate is too small. If so, adjust to more flow.

f. Check if the oil Flow rate is too high through hydraulic proportional relief valves

g. Check if the directional valve is wear out or clogged.

h. Check if the seal of the oil piston is damaged.

Pressure is normal or a little high, but cutting is slow.

a. check if high pressure tubing is clogged.

b. Check if the nozzle is clogged, wear out or damaged.

c. Check if orifice is clogged, wear out or damaged.

Too much fluctuation in water pressure.

a. Check if water supply pressure is too low.

b. Check if there is leak with outlet check valve. If yes, use the repair kit to repair it.

c. Check if there is leak at the End Bell. If there is water leak, change the HP seal with the plunger.

d. Check if there is oil leak at the End Bell. If yes, then need to change the Y-seal in the LP cylinder.

e. If any of the check valves is hot, need to replace the check valve.