Check cooling system cap

AR20.30-S-4300E

Check cooling system cap

17.07.2019

Model

447 with engine 274, 622, 651, 654

Model

448 with engine 274

Model

907 with engine 274

1

Cap

2

Adapter

3

Pressure pump

 Warning

Risk of injury to skin and eyes suffering scalding from contact with hot coolantspray. Risk of poisoning from swallowing coolant.

Do not open cooling system unless coolant temperature is below 90 °C. Open cap slowly and release the pressure. Do not pour coolant into beverage containers.
Wear protective gloves, protective clothing and safety glasses.

AS20.00-Z-0001-01A



Check

1

Turn cap (1) on the expansion reservoir counterclockwise, initially by half a revolution, relieve overpressure, and remove cap (1) from the expansion reservoir.

2

Check the cap (1) for corrosion.

If corrosion is present,



change the cap (1).

3

Attach adapter (2) to hose of pressure pump (3).

 Adapter

*210589036300

 Pressure pump

*124589242100

4

Attach cap (1) to the adapter (2).

5

 Slowly apply test pressure to cap (1) and determine opening pressure for stage 1.

 Build up test pressure with max. 0.4 bar per second until opening pressure of stage 1 is reached.
Test pressure must decrease once opening pressure of stage 1  is reached. When the valve is open, an escape of air with only a small flow volume is discernible. Overpressure valve closes max. 0.35 bar after opening pressure of stage 1 is reached.

Pressure relief valve opens

*BE20.30-N-1002-01B

If the specified values are not reached,



change the cap (1).

6

 Apply test pressure to cap (1) and determine opening pressure for stage 2.

 Quickly build up test pressure until opening pressure of stage 2 is reached. Test pressure must decrease once opening pressure of stage 2  is reached.

Pressure relief valve opens

*BE20.30-N-1002-01B

If the specified values are not reached,



change the cap (1).

7

Remove the cap (1) from the adapter (2).

8

Attach cap (1) to the expansion reservoir.

Check values for engine cooling system cap

Number

Designation

Engine 654.9 in model 447

Engine 274 in model 907

BE20.30-N-1002-01B

Pressure relief valve opens

Stage 1

New

bar

1,4 (0,1)

1,4 (0,1)

Used

bar

-

-

Stage 2

New

bar

2,0 (0,2)

2,0 (0,1)

Used

bar

-

-

Check values for engine cooling system cap

Number

Designation

Engine 274 in model 448
Engine 274, 622, 651 in model 447

BE20.30-N-1002-01B

Pressure relief valve opens

Stage 1

New

bar

1,4 (0,1)

Used

bar

-

Stage 2

New

bar

2,0 (0,1)

Used

bar

-