Takeuchi TB175W, Руководство по ремонту

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III-67 TB175W
B. Warm up engine – Next, let the engine warm up to normal operat-
ing temperature and set both fan and temperature on high. Feel both
heater supply and return hoses. If there is a noticeable difference in
their temperature, it indicates a low flow of coolant through the heater
core (a partially closed or blocked heater control valve). This could re-
sult in poor heating performance during cold weather conditions.
2. Inspect Other Functions
There are some things you can’t see or feel when you inspect the thermostat,
heater core, radiator pressure cap, electrical switch and control valve func-
tions. Some of these can be checked with the pressure and thermostat testers
as described in
Chapter 6
. A hand pump pressure tester can also be used to
check for coolant leaks. This is done by using the pump to raise the pressure
inside the system above normal operating pressure to force small suspected
leaks to show up.
Heater/cooling electrical and valve component inspection is the same as
air conditioner inspection. The controls are operated to see if they function
correctly to maintain or vary cab temperature and air flow.
Preventive Maintenance Worksheet
Please feel free to modify or copy the worksheet in Figure 7-9. Actual vehicle
use, mileage, operating conditions and maintenance budget may influence service
frequency.
Inspection & Maintenance
Figure 7-8
Heater/cooling system
potential problem areas and
checks are indicated in this
drawing.