Mainship 40 Trawler Single - Propulsion and Shaft Systems

6.1.3 Dripless Shaft Log
You may have purchased your boat with the optional
dripless shaft log seals. The dripless shaft seal receives
water from the raw water side of each engine for cool-
ing. The shaft log seal is 100 percent watertight. The
dripless shaft seal is a one-piece bearing containing
a proprietary lip seal that encompasses the propel-
ler shaft. The seal has no moving parts and remains
motionless. The centrifugal force of the shaft turning
inside the stationary housing flushes a constant sup-
ply of water lubrication through fluted grooves and out
through the shaft log. Fig. 6.1 is a view of a dripless
shaft seal showing associated parts and assemblies.
Figure 6.2
Parts List for Fig. 6.2
1. Shaft Log
2. Flexible Coupling
3. Water Injection Fitting
4. Shaft
5. Shaft Coupling
6. Hose Clamps
7. Seal Carrier
Underwater Gear
Your underwater gear consists of the following:
• Propulsion Components
• Steering Components
• Trim Tabs
• Seawater Intake
• Monitoring Equipment
• Anchor and Windlass
6.1 Propulsion Components
Propulsion components are any component that would
be involved in the movement of your boat. This sec-
tion will detail the components that are submerged or
underwater most of the time.
6.1.1 Propellers
The propeller supplied with your Mainship boat has
been selected as the best propeller for average use.
Consider keeping an extra propeller on your boat. If
the propeller becomes damaged, you can replace it
with a spare and continue your outing. Check with your
Mainship dealer if you want to purchase an extra pro-
peller.
Note: You, as owner, can change propeller sizes to suit
different conditions. However, Mainship Corporation
assumes no liability for performance and damage
caused by the change in propeller size.
6.1.2 Propeller Shaft
The propeller shaft is made of stainless steel Aquamet,
which has excellent corrsion resistance and very
high strength. The coupling at one end of the shaft is
bolted to the transmission. The other end of the shaft
is tapered, threaded and keyed for installation of the
propeller. The propeller shaft pass through the hull
encased in the shaft log. Then, on the underside of the
hull, is attached a strut, which holds the propeller shaft
in postion.
1
2
3
4
5
6
7
Propeller Shaft
Propeller Shaft
Dripless Shaft Seal
(Encases the shaft at the
shaft log)
Shaft Log
Strut (underside of boat)
Figure 6.1
Mainship 40 Trawler Single & Twin • Underwater Gear
6.2