07.3-135 Testing injection valves
Preceding work: Removing and installing injection valves (07.3-215). | Operation No. of operation texts and work units or standard texts and flat rates 07-6500 |
Basic and national version as of 1986
Injection valves (92) | test. |
Rough leaktightness test | a) Connect removed injection valves to tester. Bleed pressure line with shutoff cock open and union nut open. Following this, tighten union nut. b) Shutoff cock open; slowly operate hand lever (4s/stroke) and build up pressure to max. 1.5 bar gauge. If a leak is detected at the injection valve, the injection valve must be replaced. |
Test opening pressure | See test data for new injection valves. |
Precision leaktightness test | Close shutoff cock. Flush through injection valve by operating hand lever rapidly several times, open shutoff cock and increase pressure slowly up to 0.5 bar gauge pressure below the previously determined opening pressure, and hold. No drop must form at the injection valve within 15 seconds. |
Chatter test, assessing spray jet | Close shutoff cock and flush through valve by operating hand lever several times (0.5 sec/ stroke). Following this, reduce lever speed to approx. 1 s/stroke. This must cause the valve to chatter. No drop must form at the mouth of the valve. No string jet must form. Unilateral, atomized jet formation within a total spray angle of approx. 35° is permissible. |
Test data
Engine | MB Part No. | Ejection or opening pressure in |
for new injection valves | for used injection valves at least | |||
102 | up to 08/88 | 000 078 40 23 | 3.5-4.1 | 3.0 |
as of 09/88 | 000 078 56 23 2) | 3.7-4.3 | 3.2 | |
1) Injection valves which are out of tolerance must be replaced. Injection valves can be replaced individually within a set.
2) Brass injection valves.
Tightening torques Nm
Injection lines to fuel distributor (reference value) | 10-12 |
Injection lines to injection valves (reference value) | 10-15 |
Commercially available testers and accessories (pay attention to note)
Bosch valve tester KDJE-P 400 | Bosch order designation |
Nozzle tester EFEP 60 H 1) | Bosch No. 0 684 200 700 |
0 - 6 bar pressure gauge, housing 100 mm | Bosch No. 1 687 231 000 |
Pipeline | Bosch No. 1 680 750 001 |
Adapter 2) | Bosch No. KDJE-P 400/7 |
1) Corresponds to previous nozzle tester. The pressure gauge listed or the pressure gauge of pressure measuring device
100 589 13 21 00 is required for testing the injection valves.
2) An adapter must be used because of the modified M101 connection thread of the injection valves.
Note
The opening pressure, chatter, the jet and the leaktightness of the injection valves are tested with the nozzle or valve tester.
Before it is possible to commence the test of the injection valves, the tank of the tester must be filled and the tester bled. Only petroleum should be used for testing.
Assessing jet
Damaged injection valves
Formation of drops
Pencil-like jet
Stringy jet
Good injection valves
Good spray formation
Slightly unilateral atomization