Mercury 300 XS OptiMax Manual page 119

IMPORTANT: The recommended mounting height is based on performance
testing with a single‑engine application on a hull with no stepped or notched
transoms. Your performance results may vary, depending on hull design.
For best overall performance on boats with Sport Master gearcases, try to
mount the outboard so the propeller shaft centerline is even with the bottom of
the boat, as this gearcase is designed for surfacing applications.
722.6 mm
(28.45 in.)
a - Underside of transom bracket hooks
b - Bottom of the boat
c - Distance between "a" and "b"
d - Propeller shaft centerline
Item
Model
20 in. driveshaft models
c
1. Some models may not be available with this outboard.
eng
OUTBOARD INSTALLATION
c
1.
Recommended Mounting Height Range
685–732 mm (27–30 in.)
113
a
b
d
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