Owner's manual

Manual p/n: 029-0020-79-0 19
4DK Series Pumps
SUGGESTED CORRECTIVE ACTIONCONDITION POSSIBLE
CAUSE
ENGINE SPEEDS
TOO HIGH FOR
REQUIRED
CAPACITY OR
PRESSURE -
continued
Lift too high, suction
hose too small
Faulty suction hose
Blockage at suction
hose entry
Worn pump
impeller(s) or
clearance rings
Impeller blockage
● Higher than normal lift (10' / 3.1m) causes higher engine
speeds, high vacuum and rough operation.
● Use larger suction hose.
● Inner lining of suction hose may collapse when drafting and is
usually undetectable.
● Try a different suction hose on same pump; test for compari-
son against original hose.
● Clean suction hose strainer of obstruction and follow recom-
mended practices for laying suction hose.
● Keep off the bottom of the fluid supply by at least 2' (0.6m)
below the surface of the fluid.
● Repair and/or replace as needed. See heading "Pump Body/
Impeller," beginning on page 32.
● Blockage in the impeller can prevent loss of both capacity and
pressure.
● Back flushing of pumps from discharge to suction may free
blockage. Removing half of the pump body may be required.
(This is considered a major repair.)
DISCHARGE
VALVES DIFFI-
CULT TO
OPERATE
Lack of lubrication
Valve in need of
more clearance
● Recommended weekly lubrication of discharge and suction
valve. Use a good grade of petroleum base silicone grease.
● For Hale Products SVS Valves, use Never-Seize
®
White Food
Grade with PTFE.
● Add gasket to the valve cover per the truck manual.
● Multi-gasket design allows additional gaskets for more clear-
ance and free operation.
Note: Adding too many gaskets to the valve eventually
causes leakage.