Yanmar 3JH4E Service Manual page 304

9. Coolant system
• Do not use the pump for showering.
If the pump outlet is deformed for showering,
the increase in water pressure will increase
the load on the motor and cause motor
seizure.
• When sludge has built up in the bilge to be
drained, position the strainer about 20 cm
above the sludge. When the pump is
stopped, be sure there is sludge remaining
inside the pump housing.
• The specific gravity for the battery fluid is
1.25.
• Refer to your local dealer for impeller
replacement.
The local dealer will perform the following.
The impeller replacement kit includes one
impeller and 3 films for adjusting the side
gap. If after replacing the impeller the pump
does not drain, place side gap adjustment
washers underneath the bottom plate to
adjust. Select the number of films used in
accordance with the following. (When the
pump is draining, the electric current load is
about 10A for 12V and 5A for 24V. The pump
operates efficiently at these electric current
loads.)
Steps for replacement
1) Remove the impeller plate by taking out the
M4 screws and opening the top of the
diaphragm switch.
(Screw lock has been applied to the screw,
and a dryer should be used to heat the screw
before removing it.)
2) Clean the inside of the pump.
3) Grease the plate, impeller, and film for side
gap adjustment, and then reassemble the
pump by inserting first the film plate and then
the impeller.
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