155
3. Open the fillers of the radiator and preheater heat exchanger.
4. Start the preheater in the sequence as described above and immediately fill
12 l of water in the heat exchanger through the filler, screw on the filler plug. The
radiator filler should be left open. If the preheater stops spontaneously, repeat its
starting; if it still fails to start, drain water out of the system immediately. Detect and
eliminate the troubles in the preheater operation, then start the preheater and pro-
ceed with warming-up in the sequence described above.
5. Warm the engine until steam begins to come vigorously out of the radiator
filler.
6. Top up the system with the water via the radiator filler and plug up the filler
opening.
7. Continue heating the engine until the water temperature reaches 80
o
C-100
o
C
as per readings of the coolant temperature indicator on the dashboard.
8. De-energize the solenoid valve, blow through the gas ducts of the heat
ex-changer for 20-30 s and switch off the pump unit.
9. Open the cock of the cab heater.
10. Start the engine as described in subsection "Engine Start Without Preheat-
ing".
Engine stop
The running engine is shut down with the help of the engine stop knob which
is connected with lever 7 via tie rod 5 (see Fig. 24). The stop knob is located on the
front panel in the cab.
Before shutting down the engine, let it run during 1-3 min unloaded at me-
dium speed; then reduce the engine speed down to minimum and pull out the knob
as far as it will go.
RUNNING-IN A NEW TRUCK
A service life, reliability, and economical operation of the truck depend on the
initial running-in of the parts in the pre
-
service period. The running-in of the
truck may be performed prior to putting it in operation as well as in the course of
operation. The new truck should be carefully serviced within this period; and the
operation rules listed below are to be strictly observed.
In the course of the truck operation, a care of heat mode of truck units should
be taken. During an initial run of 1000 km (50 hours of engine running) proceed as
follows:
- warm the engine at a speed of 1300-1600 min
-1
;
- do not exceed the travelling speed of 5 km/h with the first gear engaged;
10 km/h, with the second one engaged; 20 km/h, with the third one engaged; 40
km/h, with the fourth one engaged and 50 km/h, with the fifth gear engaged;
- do not use the truck under heavy road conditions and with a trailer;
- tighten up the wheel fastening nuts twice: after 100-150 km and 200-300 km
as well as every time when removing and mounting the wheels on the truck hub;
- do not reduce the tire pressure.
Use the URAL-4420-10, URAL-4420-31 and the URAL-44202-0311-31
trucks over the initial run of 1000 km on hard-surface roads and articulated with a
semi-trailer having GVW 12 t maximum.
After the 1000 km (50 hours of engine running) run follow the procedure de-
scribed in the section "Maintenance in Pre-service Period".
