Isuzu 3LA, Руководство пользователя

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II. Engine Component Description
U
L-Series Diesel 16
Cylinder Head
The L-series cylinder heads are cast iron with
replaceable valve guides and valve seats. The
head casting number is embossed at the front of
the head’s casting just below the injector
nozzle bore.
Compression tests are conducted using a
compression gauge adapter used as a glow plug
insert, special tool number 5-88402-656-0.
Refer to workshop manual for procedure.
The service limit for this engine is 370 psi
(26.0 kg/cm
2
). Standard pressure is 441 psi
(31.0 kg/cm
2
). Isuzu allows an 8% variance
between cylinders on compression tests, but
there can be no more than a 15% difference
between any two cylinders.
Letters A-F represent the different
measurements that need to be taken to
determine head warpage.
Upper & Lower face warpage specifications:
Standard: 0.075 mm. (0.0029 in.)
Limit: 0.15 mm. (0.0059 in.)
Max Grinding Allowance: 0.3 mm. (0.0118 in.)
Head Height:
Standard: 64 mm. (2.5197 in.)
Limit: 63.7 mm. (2.5079 in.)
IMPORTANT: Valve depression must be
checked to ensure that it is still within
specification.
Casting #