Powerhead Reassembly And Installation - Mercury Optimax 115 Service Manual

POWERHEAD
NOTE: BE SURE that water in thermostat tester is allowed to cool sufficiently [below 130
F (56 C)] before testing the other thermostat.

Powerhead Reassembly and Installation

General
Before proceeding with powerhead reassembly, be sure that all parts to be re-used have
been carefully cleaned and thoroughly inspected, as outlined in "Cleaning and Inspec-
tion," preceding. Parts, which have not been properly cleaned (or which are question-
able), can severely damage an otherwise perfectly good powerhead within the first few
minutes of operation. All new powerhead gaskets MUST BE installed during reassembly.
During reassembly, lubricate parts with Quicksilver 2-Cycle Outboard Lubricant when-
ever "light oil" is specified. Quicksilver part numbers of lubricants, sealers and locking
compounds and tools are listed in "Powerhead General Information," preceding.
A torque wrench is essential for correct reassembly of powerhead. DO NOT attempt to
reassemble powerhead without using a torque wrench. Attaching bolts for covers, hous-
ings and cylinder heads MUST BE torqued by tightening bolts in 3 progressive steps (fol-
lowing specified torque sequence) until specified torque is reached (see "Example," fol-
lowing).
EXAMPLE: If cylinder head attaching bolts require a torque of 30 Ib. ft. (41 N·m), a) tighten
all bolts to 10 Ib. ft. (13.5 N·m), following specified torque sequence, b) tighten all bolts
to 20 Ib. ft. (27 N·m), following torque sequence, then finally c) tighten all bolts to 30 Ib.
ft. (41 N·m), following torque sequence.
1. If removed, press lower crankshaft ball bearing onto crankshaft as shown. Be sure
bearing is pressed firmly against counterweight.
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90-855347R1 JANUARY 1999