SELVA MARINE Blue Whale 250 EFI Service Manual page 250

LOWR
3. Calculate the propeller shaft shim thick-
ness (T4) as shown in the examples
below.
a
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.
Calculation formula 1:
Propeller shaft shim thickness (T4) =
29.00 + A/100 – B/100 – M6 – M7
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.
Calculated numeral
at 1/100 place
1, 2
3, 4, 5
6, 7, 8
9, 10
6-59
Lower unit
b
S69J6626
Rounded numeral
0
2
5
8
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.
Calculation formula 2:
Propeller shaft shim thickness (T'4) =
T4 – 0.30
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
Available shim thicknesses:
0.10, 0.12, 0.15, 0.18, 0.30, 0.40, and
0.50 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.
Ring nut wrench: 90890-06578
Ring nut 9:
108 N·m (10.8 kgf·m, 79.7 ft·lb)
6P23H11