Check compression pressure

AR01.00-S-1201PS

Check compression pressure

17.07.2018

Engine

642 in model 470, 471

1

Compression pressure recorder

2

Adapter

3

Screw-in piece

 Warning

Risk of injury. Skin or eye injuries may result when handling hot or glowing objects.

Wear protective gloves, protective clothing and safety glasses, if necessary.

AS00.00-Z-0002-01A

 Warning

Risk of accident from vehicle starting off by itself when engine running. Risk of injury (bruises and burns) resulting from working on the engine while it is being started or when it is running.

Secure vehicle to prevent it from starting off by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.

AS00.00-Z-0005-01A

Topical note

Notes on avoiding damage through contamination and foreign objects

AH00.00-P-5000-01A

Preparation

1

Bring engine to operating temperature (approx. 80 °C) and switch off.

 Check compression pressure for an engine is at operating temperature.

2

Remove glow plugs and check glow plug wells for contamination.

AR15.20-S-4111PS

3

Start engine via the contact switch of the compression pressure recorder (1) and allow to rotate multiple times to remove combustion residues in the cylinder.

AR01.10-S-0110PS

4

Screw screw-in piece (3) with installed check valve into glow plug hole of cylinder to be checked such that it is air-sealed.

 Screw-in fitting

*642589026300

5

Connect compression pressure recorder (1) with adapter (2) to screw-in piece (3) such that it is air-sealed.

 Screw-in fitting

*642589026300

 Compression tester

*001589762100



Check

6

Rotate engine via the contact switch of the compression pressure recorder (1) until the pressure no longer rises on the compression pressure recorder (1).

AR01.10-S-0110PS

7

Perform testing procedure in the cylinder order on the remaining cylinders in the same way.

8

Compare measured pressure values with specified test values.

Installation tolerance or new value of compression pressure

*BE01.00-N-1001-01L

Wear limit or limit value of compression pressure

*BE01.00-N-1002-01L

Compression pressure, permissible difference between the cylinders

*BE01.00-N-1003-01L

If the minimum compression pressure is undershot or the permissible difference between the individual cylinders is exceeded:



Check cylinder leakage.

AR01.00-S-1300PS



Install

9

Install glow plugs.

AR15.20-S-4111PS

Compression pressure

Number

Designation

Engine 642 in model 470, 471

BE01.00-N-1001-01L

Installation tolerance or new value of compression pressure

bar

23...30

Compression pressure

Number

Designation

Engine 642 in model 470, 471

BE01.00-N-1002-01L

Wear limit or limit value of compression pressure

bar

17

Compression pressure

Number

Designation

Engine 642 in model 470, 471

BE01.00-N-1003-01L

Compression pressure, permissible difference between the cylinders

bar

3