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COMPILER TECO/ATL
REG. CODE
1-5302-509
MODEL N°
50778
DATE OF ISSUE
10.06.99
REVISION
00
ENDORSED
DATE
10.06.99
33
DISASSEMBLY/REASSEMBLY
VIII
Valve springs
Measure the free length with a gauge.
For LGW 523 - Free length A = 39.8 mm.
Replace the spring if the length value is less than 37.3 mm.
For LGW 627 - Free length A = 45.6 mm
Replace the spring if the length value is less than 43.1 mm.
Valves, specifications
Exhaust valve A - Stem and mushroom are made of two different
materials.
2 Welded section
3 Chromium plated section
4 Section of material: X 45 Cr Si 8 UNI 3992
a
a
a
a
a
= 45°30' to 45°45'
D = 29.00 mm
Intake valve B - Material: X 45 Cr Si 8 UNI 3992
1 = Chromium plated section
a
a
a
a
a
1 = 60°30' to 60°45'
C = 33.00 mm
Valve guides and housings
The intake and exhaust guides are both made of grey iron of
phosphorous pearlitic matrix and are dimensionally the same:
Dimensions (mm):
A = 36.4 to 36.6
B = 11.045 to 11.054
C = 11.000 to 11.018
D = 5.80 to 6.20
E = 9.75 to 9.85
Note: Since they are pre-finished, the guides must no longer be
machined after they have been inserted.
There are also valve guides with outer diameters B increased
by 0.5 mm.
Valve guides, assembly
Insert the guides with a punch, taking value A into account, in
relation to the head surface.
Dimensions (mm):
A = 39.5 to 40.0
B = 7.005 to 7.020
C = 6.960 to 6.990
Play (mm):
(B-C) = 0.015 to 0.050 (B- C) wear limit = 0.10
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