SECTION 10 -- ENGINE -- CHAPTER 1
129
CYLINDER HEAD
CAUTION
Handle all parts carefully.
Do not put your hands or fingers between parts.
Wear the prescribed safety clothing, including
goggles, gloves and safety footwear.
Use tool
380000302
to remove and refit valve
springs.
Clean all parts carefully before proceeding with the
operations described below.
Cylinder Head Mating Surface Check
The mating surface of the head (1) with the cylinder
block should be checked with a rule (2) and a feeler
gauge (3).
The deformation measured on the full length of the
cylinder head must be no greater than 0.20 mm
(0.0078 in).
If it is any higher, regrind the cylinder head according
to the dimensions and warnings given in the following
figure.
MIF1058A
278
Cylinder Head Thickness
The nominal thickness A of the cylinder head is 95
±
0.25 mm (3.7401
±
0.0098 in) the maximum permis-
sible amount of metal removed must not exceed the
thickness B of 0.13 mm (0.0051 in).
NOTE:
After regrinding, check the valve recessing
and if necessary regrind the valve seats to obtain the
recessing prescribed on page 9.
MIF1059A
279
TOLERANCES
CHARACTERISTIC SUBJECT OF TOLERANCE
GRAPHIC SYMBOL
SHAPE
Flatness
Cylinder Head Hydraulic Seal Check
Check the hydraulic seal using the appropriate tools.
Using a pump, introduce water heated to
∼
90
°
C (
∼
194
°
F) at a pressure of 2 to 3 bar (29 to
43.5 psi).
If there is any leakage from the cup plugs, replace
them, using a suitable drift for their disassembly -- as-
sembly.
NOTE:
Before fitting the plugs (3, fig. 250), apply a
water--reactive sealant on their sealing surface.
If you find any leakage from the cylinder head, it must
be changed.
Содержание 90
Страница 132: ...132 SECTION 10 ENGINE CHAPTER 1 ...