Operating manual High-pressure double diaphragm pumps Cobra 40-10; Cobra 40-25
9 Trouble Shooting and Solution
54
Order number 2340851 | Edition 05/2022
9 TROUBLE SHOOTING AND SOLUTION
Malfunction
Cause
Solution
The pump does not
work.
Air motor does not work or stops.
Open and close ball valve on the pres-
sure regulator unit or briefly disconnect
compressed air supply.
No pressure indication on the pressure
gauge (air pressure regulator defec-
tive).
Disconnect compressed air supply
briefly or repair or change pressure regu-
lator.
Spray nozzle is clogged.
Clean the nozzle according to the in-
structions.
Insufficient supply of compressed air
Check compressed air supply.
Filter insert in spray gun or high-pres-
sure filter is clogged.
Clean the parts and use suitable prod-
uct.
Fluid section or high-pressure hose is
blocked (e.g., 2K product hardened).
Dismount and clean fluid section, re-
place high-pressure hose.
Grease in spool and sleeve assembly.
Degrease spool and sleeve assembly.
Occasionally, the pump stops at the re-
versal point.
Check detent body.
Poor spray pattern
Please refer to the gun manual.
Irregular pump opera-
tion: spray jet collapses
(pulsation).
Viscosity is too high.
Thin product.
Spraying pressure is too low.
Increase incoming air pressure. Use a
smaller nozzle.
Valves are clogged.
Press valve depressor.
Clean pump. If necessary, leave it to soak
in cleaning agent.
Foreign body in suction valve.
Dismantle suction valve housing, clean
and check valve seat.
Diameter of compressed air line too
small.
Assemble a larger supply line -> Chapter
Data [
Valves, packings, or pistons are worn
out.
Replace the parts.
Control air filter or work air filter is
clogged.
Check and clean it if necessary.
Highly irregular opera-
tion of the pump.
Diaphragm blocked because suctioning
is too fast.
Operate pump temporarily with ball
valve opened a minimal amount.
The pump runs evenly,
but does not suck up
any product.
The suction system's union nut is loose;
the pump is taking in air.
Tighten union nut.
Suction filter is clogged.
Clean the filter.
Valves are clogged.
Press valve depressor.
Clean pump. If necessary, leave it to soak
in cleaning agent.
Pump runs fast when
the spray gun is closed.
Valves worn.
Replace the parts.
Loss of power due to
severe icing in the air
motor
There is a lot of condensation water in
the air supply.
Install a water separator.