SELVA MARINE Blue Whale 250 EFI, Service Manual

Page: 250 / 377

LOWR
Lower unit
6-59
6P23H11
3. Calculate the propeller shaft shim thick-
ness (T4) as shown in the examples
below.
NOTE:
“ A ” and “ B ” are the deviation of the propeller
shaft housing dimension from standard. The
“ A ” mark
a
and “ B ” mark
b
are stamped on
the propeller shaft housing in 0.01 mm units.
If the
“ A ” mark or “ B ” mark is unreadable,
assume that “ A ” and “ B ” are zero and check
the free play when the unit is assembled.
Example:
If
“ M6 ” is 15.73 mm and “ M7 ” is 12.50 mm
and “ A ” is ( – 3) and “ B ” is ( – 5), then
T4 = 29.00 + ( – 3)/100 – ( – 5)/100 – 15.73 – 12.50 mm
= 29.00 – 0.03 + 0.05 – 15.73 – 12.50 mm
= 0.79 mm
If “ M6 ” is 15.73 mm and “ M7 ” is 12.50 mm
and “ A ” is (+7) and “ B ” is ( – 6), then
T4 = 29.00 + (+7)/100 – ( – 6)/100 – 15.73 – 12.50 mm
= 29.00 + 0.07 + 0.06 – 15.73 – 12.50 mm
= 0.90 mm
4. Round the numerals for the propeller
shaft shim(s) (T4) as follows.
Example:
If
“ T4 ” is 0.79 mm, then the propeller shaft
shim is 0.78 mm.
If
“ T4 ” is 0.90 mm, then the propeller shaft
shim is 0.88 mm.
5. Calculate and select the propeller shaft
shim thickness (T
’ 4) as shown in the
examples below.
Example:
If
“ T4 ” is 0.78 mm, then
T ’ 4 = 0.78 – 0.30 mm
= 0.48 mm
If “ T4 ” is 0.88 mm, then
T ’ 4 = 0.88 – 0.30 mm
= 0.58 mm
6. If the “ A ” mark or “ B ” mark is unreadable,
measure the propeller shaft free play as
shown.
7. Install the shim(s)
6
, thrust bearing
4
,
propeller shaft
5
, taper roller bearing
7
,
and claw washer
8
, and then tighten the
ring nut
9
to the specified torque.
Calculation formula 1:
Propeller shaft shim thickness (T4) =
29.00 + A/100
– B/100 – M6 – M7
Calculated numeral
at 1/100 place
Rounded numeral
1, 2 0
3, 4, 5 2
6, 7, 8 5
9, 10 8
S69J6626
a
b
Calculation formula 2:
Propeller shaft shim thickness (T ’ 4) =
T4 – 0.30
Available shim thicknesses:
0.10, 0.12, 0.15, 0.18, 0.30, 0.40, and
0.50 mm
Ring nut wrench: 90890-06578
T
R
.
.
Ring nut
9
:
108 N · m (10.8 kgf · m, 79.7 ft · lb)