Volvo Penta 230 Workshop Manual page 85

244. Lift out the crankshaft and remove the bearing
shells from the block and the caps.
The cylinder bores
245. Measure the cylinders with a 'dial bore gauge'.
Measure for greatest wear transversally, just below
the T.D.C. Measure for smallest wear longitudinally
at the B.D.C.
Cylinder diameter standard:
C-marked: 96.00–96.01 mm (3.77953–3.77992")
D-marked: 96.01–96.02 mm (3.77992–3.78031")
E-marked: 96.02–96.03 mm (3.78031–3.78071")
G-marked: 96.04–96.05 mm (3.78110–3.78150")
Oversize:
No 1: 96.3 mm (3.79134")
No 2: 96.6 mm (3.80315")
Classification
246. At each cylinder there is a letter punched into
the block, giving the class of the bore and that of the
piston. Oversizes are categorized as 'ÖD 1' and 'ÖD
2'. When reboring a cylinder, the new class must be
punched in.
Pistons
247. Measure the pistons with a micrometer 90° to
the gudgeon pin hole and 7 mm (0.2756") from the
lower edge.
Piston diameter, standard:
(C-marked) = 95.940–95.950 mm (3.77717–3.77756")
(D-marked) = 95.950–95.960 mm (3.77756–3.77795")
(E-marked) = 95.960–95.970 mm (3.77795–3.77835")
(G-marked) = 95.980–95.990 mm (3.77874–3.77913")
('ÖD-1') = 96.237–96.252 mm (3.78886–3.78945")
('ÖD 2') = 96.537–96.552 mm (3.80067–3.80126")
248. Calculate the piston clearance:
Example:
Measured cylinder bore ....... min. 96.025
(3.78051–3.7807")
Measured piston diam. ........ max. 96.015
(3.78012–2.77992")
The piston clearance should be max 0.080 mm
(.0031") before overhaul is required, overhauled en-
gines should have a clearance between 0.010 and
0.030 mm (.0004–.0012")
max 96.030 mm
min. 96.010 mm
0.010 0.020
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