///Pressure fluctuates or pulses
Intensifier: high-pressure side
Pressure fluctuates or pulses
If the pressure swings with each stroke, the pump cannot keep the line pressure steady.
Safety first: Switch off the pump, release all pressure (open the on/off valve or bleed-down valve) and lock out before you open any high-pressure part. Never put a hand or tool near a running jet.
1Check the causes, most likely first
0 of 4 checked
01Leak in one check valve or seal
Most likely
One weak side drops pressure every other stroke.
How to check: See if the dip happens on every stroke or on one side only.
| Photo | Art. no. | Description | Excl. VAT | |
|---|---|---|---|---|
 | 10084 | Spring LP-Inlet SLIV/SLIV+, 49884562
SpringKMT |
€ 4.32 | |
 | 10085 | Spring Check valve, 05147863
SpringKMT, H2O |
€ 1.90 | |
 | 10088 | Flat Outlet Poppet, 05116561
PoppetKMT, H2O |
€ 31.80 | |
 | 10089 | Retainer, Poppet, LP-IN SLIV, 10118552
PoppetKMT |
€ 42.29 | |
 | 10090 | Spring Guide, Poppet, 05116751
PoppetKMT, H2O |
€ 37.80 |
02Low or unstable inlet water
Possible
The cylinder is not fully filled when inlet pressure dips.
How to check: Watch the inlet gauge during each stroke.
03Worn or cracked orifice
Possible
A cracked orifice gives unstable flow.
How to check: Replace the orifice and compare.
04Faulty proximity switch or shift
Less likely
Late shifting gives a deep pressure dip at each stroke end.
How to check: Check the proximity switch LEDs.
Related problems
General advice based on manufacturer manuals and service practice. Always follow the manual of your machine. Not sure? .