Sea Ray 390 Sundancer, Owner'S Manual

Page: 86 / 184

390 Sundancer
®
( 425 Sundancer
®
) 4.6
S
ECTION
4 • B
ILGE
& U
NDERWATER
G
EAR
reverse the propeller after going through a weedy
area to unwrap and clear away any weeds which
may have accumulated. Although reversing will
sometimes help to unwrap lines and nets, they are
difficult to remove without hauling the boat.
Always check for loose or trailing dock lines before
getting underway. When towing a dinghy, remember
that a long line may easily become entangled with
the propeller when backing down.
B. B
ENT
P
ROPELLER AND
/
OR
S
HAFT
A badly damaged or distorted propeller or shaft is
an obvious cause of vibration. Even when the
propeller appears to be perfect, make sure it has
not been pulled off-center by the propeller key.
C. E
NGINE AND
S
HAFT OUT OF
A
LIGNMENT
Although the shaft is properly aligned when it leaves the
factory, after transit and after the boat has been in the
water a few days, the alignment should be rechecked.
The shaft coupling is the connecting point between the
shaft and the engine and the alignment should be set at
.005 or less. Refer to SHAFTS (pg. 4.9) in this section of
this Owner’s Manual.
D. C
OUPLING OUT OF
T
RUE
Although an extremely unlikely condition, check the
couplings if other efforts to correct the vibration fail.
Check the engine half of the coupling (with dial
indicator on the face) to see that it runs true with
the shaft coupling. Also check the coupling keys.
They must fit correctly to prevent forcing the
couplings off center.
E. E
NGINE
P
ART
H
ITTING
B
OAT
S
TRUCTURE
Engines are flexibly mounted to reduce transmission of
vibration to the hull structure. If some part of the engine,
such as the oil pan, reverse gear or reduction gear
housing, contacts a stringer, brace or part of the hull,
vibration will result. The flexible shaft log allows a limited
side motion of the shaft, but an excessive “whip” can
cause the shaft to strike the sides of the shaft hole or
the shaft log with resultant vibration.
F. O
THER
P
OSSIBLE
C
AUSES
Other causes of vibration include the following:
engine out of tune, a bent rudder, a worn strut
bearing, a component of the exhaust system
vibrating against the hull or improper contact
between shaft taper and the propeller hub bore.
12. O
IL
E
XCHANGE
S
YSTEM
(D
ISEL
O
NLY
)
If equipped the oil change system, located on the
inboard port stringer, forward of the port engine,
simplifies changing the oil in the engines, and
generator. The pump is self-priming and pumps in
either direction. The oil change pump is protected
by the 24 volt OIL CHANGE PUMP breaker on the
DC breaker panel on the forward bilge component
board.
O
IL
E
XCHANGE
S
YSTEM
(O
PTIONAL
)
(F
IG
. 4.6.1)
A
C
B
TO GENERATOR
TO PORT ENGINE
TO STARBOARD
ENGINE
DRAIN/FILL HOSE
PUMP
PUMP FLOW SWITCH
OPEN/CLOSE VALVE
OIL EXCHANGE UNIT
A
C
B
D
F
D
F
E
G
H
H
E
G