Yanmar 6LYA-STP Mode D'emploi page 46

(8) Replacing Cooling Fresh Water
Cooling performance drops when cooling water is contaminated with rust and scale. Even if LLC
is added, the cooling water must be periodically replaced because the properties of the agent
will degenerate.
To extract the cooling water, open the cooling water cocks (two positions) as shown in 3.4(2).
To resupply cooling water, refer to 3. 2. 4.
4.3.5 Inspection Every 500 Hrs.(or 2 yrs.)
（1）Inspection of AIternator V-Belt Tension
When the V-belt tension falls, the alternator will
fail to generate power due to V-belt slippage, the
cooling water pump will fail to supply cooling
water and overheating of the engine will
occur.
When the V-belt tension is too tight, the V-belt is
liable to earlier damage and the bearings of the
alternator and cooling water pump may be
damaged.
① Check the tension of the V-belt by pressing
the middle of the belt with your finger. With
proper flexion, the V-belt should sink 8〜
10mm.
② Loosen the set bolt and move the alternator
to adjust V-belt tension.
③ Be careful not to deposit oil on the V-belt.
If stained with oil, it is liable to slip and to
stretch. If damaged replace a V-belt.
4.3.6 Inspection Every 1000 Hrs.(or 4 yrs.)
(1) Inspecting Inner Parts of the Seawater Pump
The discharge performance of the seawater
pump falls depending on the use.
The seawater pump must be inspected
periodically. If the discharge volume of cooling
seawater has decreased: (When disassembly
servicing of the seawater pump is necessary,
consult yanmar dealer or distributor.)
①Loosen the side cover set bolts and remove
the side cover. (6 mounting bolts)
②IIuminate the inside of the the seawater
pump with a flashlight and inspect.
③When the following damage is found, disas-
assembly and maintenance are necessary:
Fuel oil
filter
[Fig.30]
Yammar P/N
[Fig.31]
_ _
43
Adjusting
bolt
Alternator
V-belt
Crank pully
V-belt
119593-42280
Lube oil cooler
Impelier
Ser water pump