3208 INDUSTRIAL AND MARINE ENGINES
DISASSEMBLY AND ASSEMBLY
DISASSEMBLE CYLINDER HEADS
FT806 Cylinder Head Stand
FT967 Adapter Plate
8S2263 Valve Spring Tester
8S7170 Valve Seat Insert Puller Group
a) remove cylinder heads
1. Fasten a hoist and put the cylinder head in
position on tool (A). Use adapter plates (1) from
tooling (A) to hold the head in place.
2. Put tension on the valve springs with tool (C)
and remove the locks.
NOTE: Later engines have only one valve spring and a
spacer instead of the inner spring.
3. Remove tool (C), retainer, springs, washer, and
valve from the cylinder head. Put identification
on the valve as to its location in the cylinder
4. Check the spring force with tool (B). The spring
force for the outer spring is 35 ± 5 lb. (15.9 ± 2.3
kg) when the length of the spring under the test
force is 1.715 in. (43.56 mm). The spring force
for the inner spring (if so equipped) is 16.5 ± 4
lb. (7.4 ± 1.8 kg) when the length of the spring
under the test force is 1.715 in. (43.56 mm).
5. Do Steps 2 through 4 again for the remainder of
6. Remove the exhaust valve seat inserts with
NOTE: The valve guides are part of the cylinder head.
Measure the bore in each valve guide .75 in. (19.0 mm)
from the outside edge on both ends of each valve guide.
The bore must be .3745 ± .0005 in. (9.512 ± 0.013 mm).
The maximum permissible bore is .3760 in. (9.550 mm).
Valve guides worn more than the maximum
specification can be made to the original size by