Mercury 225 EFI Service Manual page 553

RIGHT HAND NON-RATCHETING
2. Install a dial indicator and align the dial indicator pointer so that it is perpendicular to
and touching the "I" mark on the dial indicator tool. Tighten the indicator tool onto the
drive shaft and rotate the drive shaft so that the needle in the dial makes at least one
full revolution and comes to "0" on the dial indicator scale.
a -
b -
c -
d -
e -
3. Take the backlash readings by lightly turning the drive shaft back and forth, so as to
feel the backlash between the gears, (no movement 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-
c. Repeat step 2 above and take and record another reading. Repeat step 3 until a
4. Add the four readings together and divide the sum by four. This is your average back-
lash and it should be 0.030 in. - 0.050 in. (0.76mm - 1.27mm) (for 1.75:1 and 1.87:1
ratios). If backlash is not as indicated, gear case is not properly assembled or parts
are excessively worn and must be replaced before returning gear case to service.
5. Loosen the backlash indicator tool and remove the propeller nut, washer and pinion
nut adaptor. Remove the dial indicator and all its mounting components. Do not re-
move the bearing preload tool. The following instructions give specific instruc-
tions for its removal.
Page 6A-62
a
c
b
a
Nuts (4) (Obtain Locally)
Threaded Rod [3/8 in. (9.5mm) obtain locally]
Dial Indicator Holding Tool (91-83155)
Dial Indicator (91-58222A1)
Indicator Pointer
f - Backlash Indicator Rod (91-53459) (for 1.75:1)
Backlash Indicator Rod (91-78473) (for 1.87:1 ratio)
rection.
total of 4 backlash readings have been taken.
f
e
d
90-884294 OCTOBER 2001
57939