Hunter 31, Owner'S Manual, Page: 30 / 138

ENGINE, TRANSMISSION & DRIVETRAIN
PAGE
23
ENGINE
Follow the fuel and lubrication requirements
in the Engine Manual. Check the engine oil
level before and after operation and use a
quality motor oil (refer to Engine Manual).
Be certain the proper amount of oils is in the
crankcase at all times
Engine Alignment:
the engine should be
aligned by experienced marine service per-
sonnel. Final alignment should be done after
launching, with all normal gear aboard. A
description of the procedure follows:
The coupling flanges must come together
evenly at all points, a feeler gauge is used to
check the gap. If adjustment is necessary,
the engine is tilted up or down and/or side-
to-side until the flanges meet evenly. Severe
vibration will result from misalignment and
can cause strut bearing and shaft damage.
Alignment should be checked again after
several weeks of use. Routine checks of
coupling bolts are a must to ensure they are
tight.
Shaft Alignment:
1. Separate the coupling, move the shaft
end back to clear the pilot in the center.
2. Establish the shaft in the center of the
shaft log by raising the shaft until it touches
the top of the log
–
note position
–
lower the
shaft until it touches the bottom of the log
–
note position
–
repeat sideways and locate
shaft in the center; block shaft in this posi-
tion, using a block of wood under the shaft
packing gland.
3. Now, adjust the engine mounts to allow
the pilot on the coupling halves to slip to-
gether without moving shaft up down or
sideways.
4. Adjust the engine mounts as necessary
until a .004
”
feeler gauge will not enter any-
where along the edge of the flange between
the faces.
5. Tighten the locks on the adjustable
mounts
6. Recheck coupling with feeler, readjust if
necessary.
7. Check stuffing box (allow to drip 3 to 5
drops per minute).
Any questions or problems concerning the
engine, please contact the U.S. distributor,
Mastery Marine at (727) 522-9471, or your
local Yanmar service agent.
TRANSMISSION
Follow the lubrication requirements of the
engine manual. The oil level should be checked immediately after operation.
STUFFING BOX
The stuffing box is held to the stern bearing
by a rubber hose secured with hose clamps.
(See the Shaft and Propeller section). The
clamps should be tight and no water should
leak from this location. While underway a
slight drip from the stuffing box at the shaft
exit is necessary (three to five drops a min-
ute) and is normal. To adjust, loosen the
locknut, tighten the gland nut one-quarter turn, a retighten the locknut. If excessive wa-
ter flow persists after adjustment, replace
the packing with 3/16
”
(or 5mm) square flax
packing and then adjust as above.
NOTE: Some models use a packless seal-
ing system. Page 56 or Pages 56A, B, C,
reflects the type of stuffing box used on
this model.