YANMAR Diesel Engine 1GM, 2GM, 3GMD, 3HM. Manual - part 5

IV. After launching

1) Check for water or air intake around the gland part of the stern tube and the kingston cock
fitting.

2) Make sure that the engine installation bolts and shaft joints are firmly secured.

3) Release compression with the decompression lever and slowly run the engine with the
engine starting handle. Relative compression can be determined by comparing the weight (re-
sistance when turning) of the clutch handle when placed in the neutral, ahead, and astern
positions. When there is little weight difference among the three positions, decompression is
complete. If the clutch is heavier when engaged than when disengaged, this indicates that the
shaft is not in the correct position. If the engine is operated under this condition, a broken
propeller shaft may result. Check the alignment of the propeller shaft and the engine.

V. Fuel and lubricating oil

[5-1.] Selection and handling of fuel oil

1) Choice of fuel oil Fuel oils available in countries other than those listed above
which are to equipment specification may be used. Use the chart at below to
determine correct grade of fuel.

United States

ASTM/D975

No.1-D or No.2-D diesel oil

United Kingdom

BS2869

Class A 1 or Class A 2

Air temperature

Diesel/fuel (ASTM/D975)

Below 5°C (40°F)

1-D

Above 5°C (40°F)

2-D

1-a)
As further insurance of satisfactory operation, use fuel having less than 0.5% sulphur.

1-b)
For maximum filter life, sediment and water should not exceed 0.1 %.

1-c)
To maintain proper fuel delivery during cold weather operation, use grade No.1-D diesel fuel
as defined in ASTM Designation D975 with a pour point at least 5.6°C (10°F) below the
lowest outside air temperature.

1-d)
The cetane number should be 40 minimum.
Low atmospheric temperature, as well as high altitude operation, may require use of a fuel
with a higher cetane number.

2) Storing fuel Proper fuel storage is vitally important. Keep all dirt, water and other con-
taminants out of fuel. Avoid storing fuel over long periods of time. Store fuel in a convenient
place away from buildings.

Important

Presence of water or dust in the fuel may cause failure of the engine and
early wear of the fuel injection equipment. Water and dust in the fuel
tank should be removed and clean fuel used. 

3) After each day's operation.
Fill fuel tank at the end of each day's operation. This prevents condensation in fuel tank as moist
air cools.

[5-2.] Selection of lubricating oil

1) Choice of lube oil
The selection of lube oil is very important to a diesel engine. If an unsuitable oil is used, or oil
change is neglected, it may result in damage, and a shorter engine life.
When selecting the lube oil, it must be one of the following.

2) Kinds of lube oil
Choose a lube oil with a rating higher than SAE class CC.

3) Lube oil viscosity
The viscosity of the lube oil greatly influences engine starting and running performance. The lube
oil weight number chosen should vary with the season and temperature.

4) Recommended brands of lube oil for crankcase:

SAE NO.

SAE NO.

SAE NO.

SUPPLIER

BRAND 

TEMP.

TEMP.

TEMP.

TEMP.

Below 10C

10-20C

20-35C

Over 35C

Shell

Rotella

10W,20(W)

20(W)

30, 40

50

Talona

10W

20

30, 40

50

Rimula

20(W)

20(W)

30, 40

-

Caltex

Marine

10W

20

30,40

50

Multi-
purpose

20(W),
10(W)

20

30

50

Mobile

Delvac
Special

10W

20

30

-

Delvac
20W-40

20W-40

20W-40

-

-

Delvac 1100
Series

10W, 20(W)

20(W)

30, 40

50

Delvac 1200
Series

10W, 20(W)

20(W)

30, 40

50

Esso

Estor HD

10W

20

30, 40

50

Lube HD

-

20

30, 40

50

Standard

10W

20

30, 40

50

BP

Energol

20W

20W

40

50

V1. Starting the new engine for the first time

 

Important !

Before starting the engine for the first time check carefully the following
preparations.

[6-1.] Supply of fuel oil

1) Fill fuel into the fuel tank. When you feed fuel from storage tank, put the inlet of the syphon
at the middle of the storage tank. Take care not to draw unwanted materials floating on the fuel
surface or depositing in the bottom.

2) Draining the fuel tank. Be sure to equip the fuel tank with a precipitation tank, as shown in the
figure, and install a drain cock to remove any dirt and water that accumulate. Before starting the
engine. open the drain cock to remove any precipitation and dirt.

1. Precipitation Tank
2. Drain Cock

[6-2.] Supply of lubricating oil
1) Lube oil to the crankcase

1-a)
Remove the lube oil supply port (yellow cap) and supply approved lube oil.

FOR 1GM
1. Oil Supply Port