Honda BF40D Manual page 96

6) Remove the cylinder head assembly from the cylinder
block.
1
7) Remove the cylinder head gasket and the two 6 x 10 mm
dowel pins from the cylinder block.
2
Replace the cylinder head gasket with a new one on
reassembly.
3
4
5
6
7
8
9
10
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12
13
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17
8) Get a commercially available 3 mm screw [pitch: 0.5 mm
(0.02 in)] on hand.
18
Screw the 3 mm screw into the oil path orifice and remove
the oil path orifice.
19
Replace the O-ring with a new one on reassembly.
20
9-5
[2]
CYLINDER
BLOCK
[1]
CYLINDER HEAD
ASSEMBLY
[1]
3 mm screw
[pitch: 0.5 mm (0.02 in)]
(Commercially available)
96
[3]
6 x 10 mm
DOWEL PIN (2)
[4]
CYLINDER HEAD
GASKET
[2]
4.8 x 1.9 mm
O-RING
[3]
OIL PATH
ORIFICE