Venting heater

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Post by admin » Site Admin » Sat Sep 22, 2012 8:13 pm
Joined: Fri Aug 24, 2012 5:56 pm
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With the engine at rest ensure that the radiator is completely filled and fit filler cap.

Early models with water control valve fitted to the end of the ventilator assembly inside the cab.

Disconnect heater hose from thermostat housing and temporarily attach another hose to the thermostat housing outlet.

The temporary hose needs to be long enough for the free end to be held above the top of the heater.

Later models with water control valve on top of the heater box under the bonnet as in illustration (Opel diesel engine shown).

Disconnect heater hose from the heater water valve outlet.

All models: place water control valve lever in the 'hot' position.


With the free end of the hose to the engine raised above heater slowly add coolant to water system until coolant flows from the water valve outlet.

Reconnect heater hose to water valve then run engine for a few minutes and check operation of the heater.

Stop engine and check level of coolant in radiator. Level should be 25mm (1 in.) below bottom of radiator filler neck.


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