MerCruiser 305 CID (5.0L), Руководство по обслуживанию

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5.0l / 305 cid / 5.7l / 350 cid ENGINES SERVICE MANUAL NUMBER 24
Page 3A-84 90-861327--1 OCTOBER 1999
10. Check cylinder head gasket surfaces for warp with a machinist’s straight-edge and a
feeler gauge. Take measurements diagonally across surfaces (both ways) and straight
down center. If surfaces are warped more than .003 in. (0.07 mm) in a 6 in. area or .007
in. (0.2 mm) overall, block must be resurfaced by an automotive machine shop.
72388
a
b
a - Machinist’s Straight-Edge
b - Feeler Gauge
CYLINDER CONDITIONING
NOTE: Performance of the following operation depends upon engine condition at time of
repair.
NOTE: If cylinder block inspection indicates that block is suitable for continued use (except
for out-of-round or tapered cylinders), they can be conditioned by honing or boring.
1. If cylinders have less than .005 in. (0.127 mm) taper or wear, they can be conditioned
with a hone and fitted with high limit standard size piston. A cylinder bore of more than
.005 in. wear or taper may not clean up entirely when fitted to a high limit piston. To
entirely clean up the bore, it will be necessary to rebore for an oversize piston. If more
than .005 in. taper or wear, bore and hone to smallest oversize that will permit complete
resurfacing of all cylinders.
2. When pistons are being fitted and honing is not necessary, cylinder bores may be
cleaned with a hot water and detergent wash. After cleaning, swab cylinder bores
several times with light engine oil and a clean cloth, then wipe with a clean dry cloth.
CYLINDER BORING
IMPORTANT: Before using any type boring bar, file top of cylinder block to remove
dirt or burrs. This prevents boring bar tilt, (the rebored cylinder wall is not at right
angles to crankshaft.)
1. File top of cylinder block to remove dirt and burrs.
2. Measure piston to be fitted with a micrometer, measuring at center of piston skirt and
at right angles to piston pin. Bore cylinder to same diameter as piston and hone to give
specified clearance.
NOTE: Hone cylinders as outlined under “Cylinder Honing” and “Piston Selection,”
following.
3. Carefully observe instructions furnished by manufacturer of equipment being used.
Index