Check compression pressure

AR01.00-S-1201EG

Check compression pressure

24.10.2018

Model

447, 448 with engine 274

Model

907 with engine 274

1

Electrical feed line

2

Compression pressure recorder

3

Thread adapter

 Danger

Risk of explosion caused by fuel igniting, risk of poisoning caused by inhaling and swallowing fuel as well as risk of injury to eyes and skin caused by contactwith fuel.

No fires, sparks, open flames or smoking. Pour fuels into suitable and appropriately marked containers only.
Wear protective clothing when handling fuel.

AS47.00-Z-0001-01A

 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

 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

Topical note

Notes on avoiding damage through contamination and foreign objects

AH00.00-P-5000-01A



Remove

1

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

 Only check compression pressure for an engine is at operating temperature.

2

Switch off ignition and store transmitter key outside of transmitter range (min. 2 m).

3

Remove spark plugs (R4).

Model 907 with engine 274

AR15.12-D-1010TSC

Model 447, 448 with engine 274

AR15.12-S-1010EG

4

Connect electrical feed lines (1) of compression pressure recorder (2) and crank engine using contact switch at compression pressure recorder (2).

Model 907 with engine 274

AR01.10-D-0010-01TSC

Model 447, 448 with engine 274

AR01.10-S-0010-01E

 Crank engine for approx. 5 s to remove combustion residues from cylinders.

 Compression tester

*001589762100

 Electrical connection kit

*220589009900

5

Screw thread adapter (3) into spark plug thread.

 Screw-in fitting

*270589019100

6

Attach compression pressure recorder (2) to thread adapter (3).

 Compression pressure recorder (2) and thread adapter (3) must attach in an airtight manner with spark plug thread.

 Compression tester

*001589762100

 Electrical connection kit

*220589009900

 Screw-in fitting

*270589019100



Check

7

Crank engine via contact switch of compression pressure recorder (2) until pressure no longer increases in compression pressure recorder (2).

Installation tolerance or new value of compression pressure

*BE01.00-N-1001-04A

Compression pressure, permissible difference between the cylinders

*BE01.00-N-1002-04A

Wear limit or limit value of compression pressure

*BE01.00-N-1003-04A

 Compression tester

*001589762100

 Electrical connection kit

*220589009900

 Screw-in fitting

*270589019100

8

Perform test procedure in cylinder order on additional cylinders in same manner.

Installation tolerance or new value of compression pressure

*BE01.00-N-1001-04A

Compression pressure, permissible difference between the cylinders

*BE01.00-N-1002-04A

Wear limit or limit value of compression pressure

*BE01.00-N-1003-04A

 Compression tester

*001589762100

 Electrical connection kit

*220589009900

 Screw-in fitting

*270589019100

If min. compression pressure is not reached or the permissible difference between the individual cylinders is exceeded



Check cylinder leakage.

AR01.00-S-1300EG



Install

9

Remove all tools.

 Compression tester

*001589762100

 Electrical connection kit

*220589009900

 Screw-in fitting

*270589019100

10

Install spark plugs (R4).

Model 907 with engine 274

AR15.12-D-1010TSC

Model 447, 448 with engine 274

AR15.12-S-1010EG



Check

 Warning

Risk of burn injuries, suffocation and poisoning when working on the exhaust system and the components connected to it. Risk of suffocation and risk of poisoning caused by inhalation of gaseous and solid components of the exhaust. Risk of poisoning caused by skin contact with solid components of the exhaust.

Wear protective clothing and safety glasses. Use the extraction system. Move people out of the hazard area.

AS49.00-Z-0001-01A

11

Perform engine test run. While doing so, check engine for proper operation and leak tightness.

Compression pressure

Number

Designation

Engine 274 in model 907

Engine 274 in model 447, 448

BE01.00-N-1001-04A

Installation tolerance or new value of compression pressure

bar

13,5...17,5

13,5...17,5

Compression pressure

Number

Designation

Engine 274 in model 907

Engine 274 in model 447, 448

BE01.00-N-1002-04A

Compression pressure, permissible difference between the cylinders

bar

1,5

1,5

Compression pressure

Number

Designation

Engine 274 in model 907

Engine 274 in model 447, 448

BE01.00-N-1003-04A

Wear limit or limit value of compression pressure

bar

11,5

11,5