Selecting The Reverse Gear Shim - SELVA MARINE Blue Whale 250 EFI Service Manual

LOWR
5. Calculate the pinion shim thickness (T3)
as shown in the examples below.
NOTE:
"P" is the deviation of the lower case dimen-
sion from standard. The "P" mark a is
stamped on the trim tab mounting surface of
the lower case in 0.01 mm units. If the "P"
mark is unreadable, assume that "P" is zero
and check the backlash when the unit is
assembled.
Calculation formula:
Pinion shim thickness (T3) =
82.00 + P/100 – M3 – M4
Example:
If "M3" is 50.75 mm and "M4" is 30.57 mm
and "P" is (+2), then
T3 = 82.00 + (+2)/100 – 50.75 – 30.57 mm
= 82.00 + 0.02 – 50.75 – 30.57 mm
= 0.70 mm
If "M3" is 50.70 mm and "M4" is 30.53 mm
and "P" is (–3), then
T3 = 82.00 + (–3)/100 – 50.70 – 30.53 mm
= 82.00 – 0.03 – 50.70 – 30.53 mm
= 0.74 mm
6. Select the pinion shim(s) (T3) as follows.
Calculated numeral
at 1/100 place
1, 2
3, 4, 5
6, 7, 8
9, 10
6-55
Lower unit
Rounded numeral
0
2
5
8
Available shim thicknesses:
0.10, 0.12, 0.15, 0.18, 0.30, 0.40, and
0.50 mm
Example:
If "T3" is 0.70 mm, then the pinion shim is
0.78 mm.
If "T3" is 0.74 mm, then the pinion shim is
0.72 mm.

Selecting the reverse gear shim

1. Turn the thrust bearing 1 2 or 3 times to
seat the bearing retainer 2, and then
measure the bearing height (M1) as
shown.
NOTE:
• Select the shim thickness (T1) by using the
specified measurement(s) and the calcula-
tion formula.
• Measure the bearing retainer at 3 points to
find the height average.
Digital caliper 3: 90890-06704
2. Calculate the reverse gear shim thick-
ness (T1) as shown in the examples
below.
6P23H11