Mercury 225 EFI, Service Manual

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RIGHT HAND NON-RATCHETING
90-884294 OCTOBER 2001 Page 6A-61
3. Take the backlash readings by lightly turning the drive shaft back and forth, (no move-
ment should be noticed at the propeller shaft).
a. Observe the dial indicator and record the reading.
b. Loosen the indicator tool and rotate the drive shaft 90 degrees in a clockwise di-
rection.
c. Repeat step 2 above and take and record another reading. Repeat step 3 until a
total of 4 backlash readings have been taken.
4. Add the four readings together and divide the sum by four. This is your average back-
lash, which should be 0.017 in. - 0.028 in. (0.431 mm - 0.711 mm) (for 1.64:1; 1.75:1
and 1.87 ratios).
5. If backlash is LESS than the specified minimum, REMOVE shim(s) from in front of for-
ward gear bearing race to obtain correct backlash. When reinstalling pinion nut, apply
Loctite 271 to threads of nut.
6. If backlash is MORE than the specified MAXIMUM, add shim(s) in front of forward
gear bearing race to obtain correct backlash. When reinstalling pinion nut, apply Loc-
tite 271 to threads of nut.
NOTE: By adding or subtracting 0.001 in. (0.025 mm) shim, the backlash will change
approximately 0.001 in. (0.025 mm).
Reverse Gear Backlash
CHECKING
Reverse Gear Backlash – 0.030 in. to 0.050 in. (0.76mm to 1.27mm)
Although reverse gear backlash is not adjustable, it may be checked as follows:
NOTE: Torque cover nut to 210 lb. ft. (285 Nm).
1. Apply backward pressure on the propeller shaft as follows:
a. Install the pinion nut adaptor, washer and propeller nut as shown.
23355
a
b
c
a - Pinion Nut Adaptor (91-61067A2)
b - Washer (12-54048)
c - Prop Nut
b. Torque the propeller nut to 45 lb. in. (5 Nm). Rotate the drive shaft 3 full turns in
a clockwise direction and retorque the propeller nut to 45 lb. in. (5 Nm).