Replace valve stem seals.

AR05.30-G-3510DD

Replace valve stem seals.

21.08.2019

Engine

900.91/92 in model 000.001

Engine

902.91/93 in model 000.001

Engine

904.94/95/96/97 in model 000.001

Engine

906.90/93/94/95/96/98/99 in model 000.001

Engine

924.91/93/94 in model 000.001

Engine

925.9 in model 000.001

Engine

926.91/92/93/95/97/98 in model 000.001

Modification notes

08.03.2019

Document completely revised

1

Valve stem seal

4

Valve spring retainer

2

Valve guide

5

Valve spring

3

Valve lock

6

Assembly cartridge guide

2

Valve guide

7

Drift

8

Cylinder brush

9

Exhaust valve

10

Intake valves

 Danger

Risk of explosion due to escaping combustible gas or overheating of gas cylinders.Risk of injury caused by burns to skin and eyes. Risk of frostbite to body parts caused by escaping gas and by touching components near the valves when emptying gas cylinders. Risk of poisoning or suffocation caused by inhaling gas.

Remove any sources of ignition.
Protective clothing, safety gloves and safety glasses must always be worn.
Ensure that the work area is adequately ventilated.
When working on vehicles at ambient temperatures over 60 °C, all gas cylinders must be removed.

AS00.00-Z-0018-01A

 Caution

Risk of injury to skin and eyes due to handling of engine oil. Risk of poisoning caused by swallowing engine oil

Wear protective gloves, protective clothing and safety glasses.
Do not fill engine oil into beverage containers.

AS18.00-Z-0001-01A

Topical note

Notes on avoiding damage through contamination and foreign objects

AH00.00-N-5000-01H

Notes on work safety regulations for vehicles with natural gas-powered engines

AH00.10-N-1000-04A



Remove

1.1

Remove spark plugs.

With natural gas engine

AR15.12-G-1010DE

1.2

Remove nozzle holder combination.

With diesel engine

AR07.03-G-6831DD

2

Remove cylinder head.

Diesel engine

AR01.30-G-5800DD

Natural gas engine

AR01.30-G-5800DE

3

Remove valve springs (5) and valve stem seals (1).

AR05.30-G-3510-02DD



Exhaust valve spring, exhaust valve and exhaust valve seat ring modified

BT05.30-N-0004-01RH

 Magnetic pin

*210589004000

 Valve tool case

*541589006100

 Pliers

*606589003700

4

Mark intake valves (10) and exhaust valves (9) and remove from cylinder head.

5

Clean valve guides (2) using cylinder brush (8).

 Cylinder brush

*000589106800



Check

6

Check whether intake valves (10) and exhaust valve (9) can be re-used.



Exhaust valve spring, exhaust valve and exhaust valve seat ring modified

BT05.30-N-0004-01RH

 The valve stems must have no surface damage.
The grooves for the conical valve keepers (3) must not be worn out.
The valve seats must not be burnt.

If burning or damage is detected:



Replace the corresponding intake valve (10) or exhaust valve (9).

7

Check the inside diameter of valve guides (2) in cylinder head.

Inside diameter (machined dimension)

*BE05.30-N-1003-02J

 Drift

*102589002300

If the drift (7) side marked with "+" can be inserted into valve guide (2):



Replace corresponding valve guide (2).

AR05.30-G-3731DD



Install

8

Insert intake valves (10) and exhaust valve (9) into cylinder head.



Exhaust valve spring, exhaust valve and exhaust valve seat ring modified

BT05.30-N-0004-01RH

9

Install valve springs (5) and new valve stem seals (1).

AR05.30-G-3510-02DD

 Magnetic pin

*210589004000

 Valve tool case

*541589006100

 Pliers

*606589003700

10

Install cylinder head.

Diesel engine

AR01.30-G-5800DD

Natural gas engine

AR01.30-G-5800DE

11.1

Install spark plugs.

With natural gas engine

AR15.12-G-1010DE

11.2

Install nozzle holder combination.

With diesel engine

AR07.03-G-6831DD

Check values for valve guides

Number

Designation

ENGINE 900.9, 902.9

ENGINE 904.9## (except 904.971) ## up to 039739, 924.9## ## up to 039739, ENGINE 906.9## (except 906.901/902) ## up to 041955

BE05.30-N-1003-02J

Inside diameter (machined dimension)

mm

8,000...8,022

8,000...8,022

Check values for valve guides

Number

Designation

ENGINE 904.9, 924.9## ## as of 039740, ENGINE 906.9## ## as of 041956, ENGINE 906.901/902 ## up to 041955

Engine 925.9 in model 000.001

BE05.30-N-1003-02J

Inside diameter (machined dimension)

mm

8,000...8,022

8,000...8,022

Check values for valve guides

Number

Designation

ENGINE 926.9## ## up to 041955

ENGINE 926.9## ## as of 041956

BE05.30-N-1003-02J

Inside diameter (machined dimension)

mm

8,000...8,022

8,000...8,022