General Pump Pump Installation and Service Manual - Manual (Page 9)

9
PROBLEM CAUSE REMEDY
Pulsation
Valve stuck open. Check all valves, remove foreign matter.
Faulty pulsation damper. Check precharge; if low, rechargeit or install a new one.
Low pressure
Worn nozzle. Replace nozzle, of proper size.
Belt slippage. Tighten or replace; use correct belt.
Air leak in inlet plumbing. Disassemble, reseal and reassemble.
Relief valve stuck; partially plugged or
improperly adjusted valve seat worn.
Clean, adjust relief valve; check for worn and dirty
valve seats. Kit available.
Inlet suction strainer clogged or improperly sized. Clean. Use adequate size. Check more frequently.
Worn packing. Abrasives in pumped fluid
or severe cavitation. Inadequate water.
Install proper filter. Suction at inlet manifold must be limited
to lifting less than 20 feet of water or -8.5 PSI vacuum.
Fouled or dirty inlet or discharge valves. Clean inlet and discharge valve assemblies.
Worn inlet, discharge valve blocked or dirty.
Replace worn valve seats and/or discharge hose
Leaky discharge hose.
Pump runs extremely rough,
pressure very low.
Restricted inlet or air entering the inlet plumbing. Proper size inlet plumbing; check for air tight seal
Inlet restrictions and/or air leaks. Stuck
inlet or discharge valve.
Replace worn cup or cups, clean out foreign material,
replace worn valves.
Water leakage from under
manifold. Slight leakage.
Worn packing. Install new packing.
Cracked plunger. Replace plunger(s).
Oil leak between crankcase
and pumping section.
Worn crankcase piston rod seals. O-rings
on plunger retainer worn.
Replace crankcase piston rod seals. Replace
o-rings.
Oil leaking in the area of
crankshaft.
Worn crankshaft seal or inproperly
installed oil seal o-ring.
Remove oil seal retainer and replace damaged
o-ring and/or seals.
Bad bearing.
Replace bearing and any spacer or cover damaged
by heat.
Excessive play in the end of
the crankshaft pulley.
Worn main bearing from excessive
tension on drive belt.
Replace crankcase bearing and/ or
tension drive belt.
Water in crankcase.
May be caused by humid air condensing i
nto water inside the crankcase
Change oil intervals. Use General Pump SAE 30
non-detergent oil.
Worn packing and/or piston rod sleeve,
o-rings on plunger retainer worn.
Replace packing. Replace o-rings.
Cracked plunger Replace plunger(s).
Oil leaking from underside
of crankcase.
Worn crankcase piston rod seals. Replace seals.
Scored piston rod. Replace piston rod.
Oil leaking at the rear portion
of the crankcase.
Damaged crankcase, rear cover o-ring,
drain plug o-ring, or sight glass o-ring.
Replace cover or-ring, drain plug o-ring, or sight
glass o-ring.
Loud knocking noise in pump.
Pulley loose on crankshaft. Check key and tighten screw.
Broken or worn bearing on rod(s). Replace bearing or rod(s).
Valve stuck open or shut, or not opening enough. Replace bad valve.
Frequent or premature failure
of the packing.
Scored, damaged or worn plunger. Replace plungers.
Overpressure to inlet manifold. Reduce inlet pressure.
Abrasive material in the fluid being pumped. Install proper filtration on pump inlet plumbing.
Excessive pressure and/or temperature
of fluid being pumped.
Check pressures and fluid inlet temperature; be
sure they are within specified range.
Overpressure of pump. Reduce pressure.
Running pump dry. Do not run pump without water.
Upstream chemical injection. Use downstream chemical injection.
TROUBLESHOOTING