Test compression pressure

AR01.00-S-1200C

Test compression pressure

15.11.2019

Engine

104.900 in model 638.2

1

Spark plug

2

Ignition coil

3

Compression pressure recorder

4

Throttle valve

 

Remove/install

1

Warm up engine to normal operating temperature

 Coolant temperature 80°C.

 Danger

Risk of death when working on component parts and systems with U >= 30 V alternating voltage (AC) or U >= 60 V direct voltage (DC)

Do not touch damaged or defective live component parts and lines or non-insulated electrical connections and lines.

AS00.00-Z-0035-01A

2

Remove spark plugs (1)



AP15.10-S-1580A

3

Disconnect connector for ignition coil (2)

4

Install in the reverse order

Check

 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

5

Crank engine with starter

6

Guide compression recorder (3) into bore of spark plug (1)

 Compression tester

*001589762100

7

Depress accelerator pedal as far as it will go

8

Crank engine with starter

 To check compression pressure, crank engine through at least 8 cycles.

9

Carry out the test procedure on the other cylinders in the same way



Check

10

Check compression pressure

When new

*BE01.00-N-1001-01A

Wear limit (limit value)

*BE01.00-N-1002-01A

Permissible difference between individual cylinders

*BE01.00-N-1003-01A

Check values for compression pressure

Number

Designation

Engine 104.900

BE01.00-N-1001-01A

When new

bar

10–13

Check values for compression pressure

Number

Designation

Engine 104.900

BE01.00-N-1002-01A

Wear limit (limit value)

bar

7,5

Check values for compression pressure

Number

Designation

Engine 104.900

BE01.00-N-1003-01A

Permissible difference between individual cylinders

bar

3