Machine valve seat rings

AR05.30-G-4511MT

Machine valve seat rings

11.11.11

6.11.06

Inside dia. (B)

Engine 447.903

*BE05.30-N-1001-02O



Removing

1

Remove valve spring

AR05.30-G-3511MT

2

Clamp cylinder head onto cylinder head holding fixture

Cylinder head holding fixture



Checking

3

Measure valve setbacks on intake and exhaust valves to cylinder head

 Record measured values for valve setbacks.

AR05.30-G-4100-01MT

 If the reading obtained is not within the permissible tolerance, the valves must be inspected.

If wear is found, fit new valves and check the valve seat rings (1).



Remove/install valves

AR05.30-G-3511MT

*BE05.30-N-1002-01O

*BE05.30-N-1012-01O



*001589532100



*343589004000

4

Pull valves out of cylinder head

 Mark valves relative to the corresponding cylinder head.

5

Inspect valve seat rings (1, 2)

 Slightly stamped in valve seat rings (1, 2) can be reworked.

If valve setbacks measured in operation step 3 are not within the tolerance range or the valve seat rings (1, 2) are heavily stamped in: 

Replace valve seat rings

AR05.30-G-3831MT

6

Use a feeler gauge to check the inside diameter of the valve guides for wear

 If side marked with "+" of the plug gage can be placed in the valve guide then the valve guide must be replaced: 

Check, remove/install valve guides

AR05.30-G-3731MT

*BE05.30-N-1001-02O



*100589102100

Machining

7

Machine valve seat rings (1, 2) in the cylinder head

 If values after machining are below the Check values:



AR05.30-G-4532-01MT

Replace valve seat rings

AR05.30-G-3831MT

*BE05.30-N-1007-03M

*BE05.30-N-1008-03M



*366589006900



Checking

8

Inspect concentricity of valve seat relative to valve guide

 Use a testing set for valve seats to check smooth operation of the valve seat.

AR05.30-G-4532-02MT

 Rework intake valve and exhaust valve seat rings if there is any deviation from Check values: 

Machining valve seat rings with a turning tool

AR05.30-G-4532-01MT

*BE05.30-N-1002-02O

*BE05.30-N-1003-02O



*366589006900



Install

9

Install valves

 The used valves must be ground before installation if no new valves are used:



AR05.30-G-3511MT

Grind valves

AR05.30-G-4202MT

10

Measure valve setbacks again on both intake and exhaust valves

AR05.30-G-4100-01MT

*BE05.30-N-1002-01O

*BE05.30-N-1012-01O



*001589532100



*343589004000

Number

Designation

Engine
447.903

BE05.30-N-1002-01O

Valve setback relative to cylinder head contact surface

mm

0.7 to 1.1

BE05.30-N-1012-01O

Permissible difference between valve setback to cylinder head separating surface

Inlet

mm

0.2

Outlet

mm

0.2

Number

Designation

Engine
444.901

BE05.30-N-1002-01O

Valve setback relative to cylinder head contact surface

mm

0.7 to 1.1

BE05.30-N-1012-01O

Permissible difference between valve setback to cylinder head separating surface

Inlet

mm

0.2

Outlet

mm

0.2

Number

Designation

Engine
444.901,
447.903

BE05.30-N-1001-02O

Valve guide

Outer dia. (A)

Default

mm

18.028 to 18.046

Deviation 0.2

mm

18.235 to 18.256

Deviation 0.4

mm

18.435 to 18.456

Bore dia. in cylinder head (A1)

Standard

mm

18.000 to 18.018

Deviation 0.2

mm

18.200 to 18.221

Deviation 0.4

mm

18.400 to 18.421

Inside dia. (B)

pressed in

mm

12.000 to 12.027

Length (C)

mm

67.0

Distance (D) top edge

Inlet

mm

17.1 to 17.5

Valve guide to contact surface of valve spring

Outlet

mm

17.1 to 17.5

See picture

AR05.30-G-3731MT

BE05.30-N-1002-02O

Valve seat center offset to valve guide

mm

0.02

BE05.30-N-1003-02O

Valve seat concentricity relative to valve guide

mm

0.04

Number

Designation

Engine
444.901,
447.903

BE05.30-N-1007-03M

Valve seat

Valve seat angle at valve seat (J)

Intake

°

30

Outlet

°

45

Valve seat width at valve seat (F)

Intake

mm

1.8 to 3.0

Outlet

mm

1.4 to 2.6

See picture

AR05.30-G-4511MT

BE05.30-N-1008-03M

Valve seat dia. at valve seat ring (finish-machined), machining dimension (G) relative to depth (H) of cylinder head contact surface

Inlet

Dimension (G)

mm

54.99 to 55.01

Dimension (H)

mm

3.90 to 4.10

Outlet

Dimension (G)

mm

47.99 to 48.01

Dimension (H)

mm

3.10 to 3.30

See picture

mm

AR05.30-G-4511MT