Checking Boat Transom Construction - Mercury 40 jet fourstroke User Manual

Checking Boat Transom Construction

IMPORTANT: Determine the strength of the boat transom. The
outboard mounting locknuts and bolts should be able to hold
75 Nm (55 lb‑ft) of torque without the boat transom yielding or
cracking. If the boat transom yields or cracks under this torque,
the construction of the transom may not be adequate. The boat
transom must be strengthened or the load carrying area
increased.
a - Transom yielding under bolt torque
b - Transom cracking under bolt torque
When first determining transom strength, use a dial torque
wrench. If the bolt or nut continues to turn without the torque
reading on the dial increasing, it is an indication that the transom
is yielding. The load area can be increased by using a larger
washer or a transom reinforcement plate.
eng
OUTBOARD INSTALLATION
a
121
b
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