Test Preparation

Data:
Permissible leaks per vacuum circuit (without vacuum reservoir)
- 30 mbar/min at 400 mbar vacuum
Permissible leaks in check valves
- 50 mbar in 10 min at 300 mbar vacuum
Permissible leaks in remaining components
- 20 mbar/min at 300 mbar vacuum
Plug-on length of connections
- 10-12 mm

Special Tools:
Tester for vacuum systems
- 116 589 25 21 00
Distributor
- 115 805 03 22

Self-Made Tool:
1 Blind plug
- Welding wire 4 mm dia. 40 mm long

Note:
The vacuum system is subdivided into 8 test circuits. If a given trouble prevails (e.g. center nozzle not opening) the respective circuit can be tested first.

If a leak or functional trouble is suspected in entire vacuum unit, proceed according to "Testing Check Valve and Vacuum Reservoir" and perform each time the first test step (total test) of the individual vacuum circuits until the faulty vacuum circuit is found. Then continue testing the respective circuit until the actual fault is found.

Preparing For Test:






1. Run engine warm to approx. + 60 °C. Cold engine lock (31 is switched off. Then shut off engine again.






2. Push function selection button "d".