2. Turn off the ignition and remove the key.
3. Remove glow plugs R13-R16 (see figure 5.70).
Figure 5.70. Checking engine compression:
1. Compression gauge,
2. Adapter,
3. Threaded adapter,
R13-R16. Glow plugs.
4. Turn the engine crankshaft with the starter. Disconnect the wiring connector from the Y74 Distributor Pressure Control Valve.
5. Connect compression tester 1 to adapter 2. Screw threaded adapter 3 into the glow plug hole of the cylinder being tested.
(Material borrowed from an online resource: mercedesman.ru)
6. Turn the engine crankshaft with the starter and record the obtained compression value. Compare the obtained value with the required one.
- Compression of a new engine: 29-35 bar.
- Worn engine compression: 18 bar.
- Permissible difference between readings of individual cylinders: 3 bar.
If the compression is below the minimum acceptable level or the difference between the readings of individual cylinders is greater than acceptable, check for leaks.