Lovol 1004-4, User Handbook Manual, Page: 41 / 87

Air filter
Environmental conditions have an important effect on the frequency at which the air filter needs service. Certain air
filters have a separate dust bowl (A1) which must be cleaned at intervals. The amount of dust in the bowl shows if it
has been removed at the correct time for the conditions of operation. Do not let dust completely fill the bowl, because
this will reduce the life of the filter element (A2).
Certain air filters have automatic dust valves (B1) through which dust is expelled from the filter. The rubber dust
valve must be kept clean. Ensure that the sides of the valves close completely together and that they can separate
freely.
If a restriction indicator (C) is fitted, it will indicate precisely when the air filter element needs service. This prevents
the premature removal of the filter element which causes extra cost or late removal to the element which can cause
loss of engine power.
The filter element must be cleaned or renewed according to the manufacturer's recommendations.
Restriction indicator
The restriction indicator for these engines must work at a pressure difference of 508/558 mm of water gauge. It is
fitted on the air filter outlet or between the air filter and the induction manifold.
When the red warning indicator (C1) is seen through the clear panel (C2) after the engine has stopped, the air filter
element must be removed for service.
After a clean element has been fitted, press the rubber bottom (C3) or the button (C4) of the restriction indicator to
reset the red warning indicator.
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