Alignment Of Output Coupling - CAPITOL HY- 6900 Service Manual

3.4 ALIGNMENT OF OUTPUT
COUPLING
In marine application, final alignment of
output flange and propeller shaft coupling
must be accomplished when the vessel is
afloat and not in dry-dock, because most
hulls will flex. This is positively necessary to
meet warranty requirements.
Mounting feet on housing permit unit to be
bolted to bed rails, power plant frame,
keelsons, etc.
The distance of the first shaft bearing from
the mating surface of the reverse gear
output coupling is extremely important. To
avoid undue force on the reverse gear
bearings, the propeller shaft bearing should
be located at least twelve and preferably
twenty shaft diameters from the reverse
gear output coupling.
NOTE:
The same alignment procedures should be
followed even if a flexible coupling is used. The
most accurate method is to use a non-flexible
spacer of the same size first. Flexible couplings
are used only to dampen noise and vibration and
to correct minor misalignment.
Now align shaft coupling to reverse gear
coupling. Lay a straight edge across the
edges at top and sides to line up couplings.
Do not burr or mar mating surfaces. Insert
feeler gauge between couplings and run it
all around the flange. Clearance should not
be more than .006" at any point. Shim
engine and reverse gear as necessary.
Mounting feet have threaded holes for
jacking screws.
Loosen gear housing to engine housing
bolts and check with feeler gauge. Maximum
variation for SAE "0 housing is .008"; for
SAE #1 housing is .006".
Tighten four gear housing capscrews at 90º
intervals. Secure engine and gear mounting
feet. Loosen four gear-housing bolts.
Recheck housing and coupling parallelism. If
within limits tighten housing and coupling
bolts.
Be sure transmission is connected to oil
cooler.
NOTE:
Under no condition is the engine to be supported
by gear housing.
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