Water Circulating Pump; Cleaning And Inspection - Mercury MerCruiser D2.8L D-Tronic Service Manual

SERVICE MANUAL NUMBER 22

Water Circulating Pump

Refer to Cold Weather or Extended Storage, Draining Instructions in SECTION 1B and
Precautions in this section, BEFORE proceeding.
IMPORTANT: Water circulating pump on D4.2L engines is a larger volume pump and
does NOT interchange with circulating pumps on D2.8L engines.
Removal
1. Drain the seawater system.
2. Drain the closed cooling system.
3. Remove the heat exchanger.
4. Remove alternator drive belts.
5. Disconnect water circulating pump hoses.
6. Remove the pump.
7. Discard gasket.
Typical

Cleaning and Inspection

1. Remove all traces of old gasket material from water circulating pump body.
2. Remove all traces of old gasket material from engine block do NOT allow debris inside,
which might foul cooling system passages.
3. Inspect pump for blockage, cracks, sand holes, corrosion or other damage. Inspect
pump impeller for cracks and erosion. Replace complete pump, if any damage exists.
4. Check impeller shaft and bearings for excessive side play. If play can be felt, replace
complete pump.
5. Inspect pump pulley for bends, cracks, corrosion, or other damage. Inspect pulley for
runout. Replace complete pump, if pulley is damaged or untrue.
90-860074-1 FEBRUARY 2002
a - Water Circulating Pump
b - Gasket
c - Nuts
NOTICE
b
a
c
CLOSED COOLING SYSTEM
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Page 6B-31