Section 6. Lubrication System - Kohler CH940 Service Manual

General
This engine uses a full pressure lubrication system.
This system delivers oil under pressure to the
crankshaft, camshaft, and connecting rod bearing
surfaces. In addition to lubricating the bearing
surfaces, the lubrication system supplies oil to the
hydraulic valve lifters.
A high-efficiency gerotor pump is located in the
closure plate. The oil pump maintains high oil flow
and oil pressure, even at low speeds and high
operating temperatures. A pressure relief valve limits
the maximum pressure of the system.
Service
The closure plate must be removed to service the oil
pickup, the pressure relief valve, and the oil pump.
Refer to the appropriate procedures in Sections 8, 9,
and 10.
Oil Recommendations
Using the proper type and weight of oil in the
crankcase is extremely important. So is checking oil
daily and changing oil regularly. It is also
recommended that a consistent brand of oil be used.
Failure to use the correct oil, or using dirty oil, causes
premature engine wear and failure.
Use high-quality detergent oil of API (American
Petroleum Institute) service class SG, SH, SJ or
higher. Select the viscosity based on the air
temperature at the time of operation as shown in the
following table.
R E C O M M E N D E D S A E V I S C O S I T Y G R A D E S
**
*
5W-20, 5W-30
°F -20 0 20 32
°C -30 -20 -10 0
TEMPERATURE RANGE EXPECTED BEFORE NEXT OIL CHANGE
* Use of synthetic oil having 5W-20 or 5W-30 rating is acceptable,
up to 4°C (40°F)
** Synthetic oils will provide better starting in extreme cold below
23°C (-10°F)
Section 6
Lubrication System
10W-30
Kohler 10W-30
40 60 80 100
10 20 30 40
Lubrication System
NOTE: Using other than service class SG, SH, SJ or
higher oil, or extending oil change intervals
longer than recommended can cause engine
damage.
NOTE: Synthetic oils meeting the listed
classifications may be used with oil changes
performed at the recommended intervals.
However, to allow piston rings to properly
seat, a new or rebuilt engine should be
operated for at least 50 hours using standard
petroleum based oil before switching to
synthetic oil.
A logo or symbol on oil containers identifies the API
service class and SAE viscosity grade. See Figure 6-1.
Figure 6-1. Oil Container Logo.
The top portion of the symbol shows service class
such as API SERVICE CLASS SJ. The symbol may
show additional categories such as SH, SG/CC, or
CD. The center portion shows the viscosity grade
such as SAE 10W-30. If the bottom portion shows
Energy Conserving, it means that oil is intended to
improve fuel economy in passenger car engines.
Section 6
6
6.1