Operating Instructions and Parts Manual
Plunger Pumps
Troubleshooting (cont.)
Symptom
Low pressure (cont.)
Pump runs extremely
rough, pressure very
low
Water leakage from
under manifold
Slight leak, oil leak-
ing in the area of
crankshaft
Excessive play in the
end of the crankshaft
pulley
Water in crankcase
Loud knocking noise
in pump
Possible Cause(s)
3 Air leak in inlet plumbing
4 Relief valve stuck, partially
plugged or improperly
adjusted valve seat worn
5 Worn packing. Abrasive
in pumped in cavitation.
Inadequate water
6 Worn inlet, discharge valve
blocked or dirty
1 Inlet restrictions and/or air
leaks.
2 Stuck inlet or discharge
valve
Worn packing or cracked
plunger
1 Worn crankshaft seal or
improperly installed oil seal
o-ring
2 Bad bearing
Worn main bearing from
excessive tension on drive
belt
1 Humid air condensing into
water inside the crankcase
2 Worn packing and/or
cracked plunger
1 Cavitation or sucking air
2 Pulley loose on crankshaft
3 Broken or worn bearing
3 Disassemble, reseal and reas-
semble
4 Clean and adjust relief valve;
check for worn or dirty valve
seats
5 Install proper filter suction at
inlet manifold must be limited to
lifting less than 20 feet of water
or 8.5 psi vacuum
6 Replace inlet and discharge valve
1 Clean out foreign material
2 Replace worn valves
Install new packing or plunger
1 Remove oil seal retainer and
replace damaged 0-ring and/or
seals
2 Replace bearing
Replace crankcase bearing and/or
tension drive belt
1 Change oil intervals
2 Replace packing. Replace
plunger
1 Check water supply is turned on
2 Check key and tighten set screw
3 Replace bearing
en 13
RSV Series Pumps
Corrective Action
When Quality Matters