Valve Stem Sealing Rings - Reassembly; Valve Springs; Valve Material; Valve Guides And Cylinder Head Housings - Kohler KD 625/3 Workshop Manual

4
Disassembly / Reassembly
38
40
41
43
- 32 -
39
42

Valve stem sealing rings - Reassembly

Lubricate the inside of the sealing ring with Molikote BR2 Plus and in-
sert them all the way onto the guides using tool 1460 – 108.
To prevent deformation of the sealing ring 1 as it is inserted onto the
valve guide 2 insert it onto tool 3.
Lubricate valve stem with the same type of grease; insert the valves
into the guides rotating them particularly as they enter the sealing ring.

Valve springs

Measure free length with a gauge.
Using a spring tester check that the spring length under two different
loads corresponds to the values below:
Free length A = 52 mm
Length B compressed by a 21 Kg weight = 34.8 mm
Length C compressed by a 32 Kg weight = 25.8 mm.

Valve material

Intake valves A
- Material: X 45 Cr Si 9 - 3 UNI EN 10090
1 = Chromium-plated portion
α = 45°15' ÷ 45°25'
Exhaust valve B
Shaft and head are made of 2 different materials.
2 = Welded portion
3 = Chromium-plated portion
4 = Portion made of X 45 Cr Si 9 - 3 UNI EN 10090
5 = Portion made of X 53 Cr Mn Ni N 21 - 9 UNI EN 10090
α = 45°15' ÷ 45°25'

Valve guides and cylinder head housings

Intake and exhaust valve guides are both made of phosphoric cast
iron.
Components: 1 = Exhaust valve guide
2 = Intake valve guide
Ref.
A
B
C
D
Valve guides with outside diameter increased by 0,5 mm are also
available; in such cases valve guide bore C should also be increased
by 0,5 mm.
KD Workshop Manual_cod. ED0053029350_1° ed_ rev. 00
Dimensions (mm)
42.00
48.00
14.00 ÷ 14.018
14.045 ÷ 14.056