Weifang 495 - Maintenance of Fuel Filter; Calibration of the Fuel Delivery Timing

been mixed with some vlater respectIvely ..
In order to preve:nt dirt and water from entering the fuel pas-
sage, the level of the fuel tank outlet cock must be higher -enough
than that of the tank bottom.
A. maintenance of Fuel Filter
a. The paper element of the fuel filter should be flushed in
clean diesel oil after every 250 working hours. Its service life close-
.~ ly relating to the fuel cleanliness is about 500 hours. If the outer
surface is too dirty or the filter paper has been deformed, the ele-
ment should be replaced before the due time. When flushing the el-
ement, a soft brush nla'y be used to clean off the dirt on the outer
surface tenderly. To avoid dirt entering the inner space of the ele-
ment, the holes on blth ends of the element· spould -be choked up
with rubber or cork plugs in advance.
b. When installing the element ,it must be carefuel ~hat its end·
surfaces must be oil tighted and the inlet and outlet pipes on the
filter head must be connected correctly, otherwise the filter will
lose its ,.;;ffectiveness.
B. Calibration of the Fuel Delivery Timing
The fuel delivery timing should be calibrated in the 3rd order
maintenance or after reassembling the engine, the procedure is as
follows.:
a.
Mount an overflow tube on the first cylind.er delivery valve
holder of the injection pump (Fig. 24). The overflow tube consists
of a high pressure fuel pipe of 45 - 60 mm in length, a plastic (or
rubber) hose and ~ glass tube of 1. 5~2 mm in inner diameter.
b. Place· the governor control lever at the maximum fuel deliv-
ery po.sition and expel up the air from the fuel passage with the
hand puinp. Then turn the crankshaft to let the fuel level·stay still
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