Mercury 15 EFI FourStroke, Service Manual

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Dial Indicator 91‑ 58222A 1
Dial Indicator Adapter 91‑83155
9. Position the dial indicator tip so that it is perpendicular to and touching the notch in the indicator arm, as shown. Adjust the
angle of the backlash indicator arm, as required. Tighten the fasteners on the dial indicator adapter so that the dial
indicator does not move.
NOTE: Ensure that the dial makes at least one full revolution as the tip is compressed into the dial indicator.
a - Backlash indicator arm
b - Dial indicator tip
c - Dial indicator adapter
d - Dial indicator
e - Threaded rod (obtain locally)
f - Clamp on driveshaft (compresses spring)
10. Zero the dial indicator.
11. Take the backlash reading by lightly turning the driveshaft back and forth.
Forward Gear
Backlash
0.8–1.5 mm (0.031–0.059 in.)
12. If the backlash is not within specification, add or remove shims located between the upper driveshaft bearing and the water
pump base.
NOTE: Removing a 0.1 mm (0.004 in.) shim will increase the axial play value by 0.1 mm (0.004 in.).
Adding a 0.1 mm (0.004 in.) shim will decrease the axial play value by 0.1 mm (0.004 in.).
13. After making shim adjustments, repeat the measurement procedure to ensure the correct backlash specification is
obtained. Then remove all items installed for this procedure.
Shift Shaft and Water Pump Base Installation
1. Inspect the shift shaft bracket, located on the underside of the water pump base. Replace it, if it is damaged.
Description Nm lb‑in. lb‑ft
Shift shaft bracket screw 5.0 44.3 –
2. Insert the shift shaft into the water pump base. Ensure that the new shift shaft O‑ring remains properly seated.
90° 90°
a
b
c
d
e
f
64946
Gear Housing (2.15:1)
90-8M0125265 eng NOVEMBER 2017 © 2018 Mercury Marine Page 6A-35