Volvo Penta D2-55, Руководство по ремонту

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Group 21 Short block
Cylinder head, overhaul
Disassembling cylinder head
Special tools: 885 023, 885 498
1. Remove the valves (1) and valve springs (3).
Compress the springs with compressor 885 023
together with pressure foot 885 498 and remove
the valve cotters (5). Place the valves in order in
a marked valve holder, so they can be refitted in
their original positions. Remove the valve stem
seals (2).
2. Clean all components. Be especially careful with
the cylinder head oil and coolant channels.
3. Remove any remaining carbon/deposit from the
cylinder head sealing surface.
Note. A wire brush may not be used for cleaning the
cylinder head bolt threads or the underside of the bolt
heads.
F B E
A C D
Inspecting the cylinder head
Cylinder head warping must not exceed the value giv-
en in “Technical data”. The check should be done with
a feeler gauge and a straight edge. Measurement is
done at six positions (A - F).
If warpage above the permissible level is found, the
cylinder head must be changed. If leakage has been
found, or if the cylinder head has blow lines, no spe-
cial measurement is needed since such a cylinder
head will have to be attended to in any case.
Check the valve seats and check that the studs are
firmly seated.
Inspect the cylinder head for cracks. Carefully check
the areas around the valve seats and the holes for the
injector nozzles.
885 023 885 498