Ignition System; Check Spark Plugs - Kohler CH640 Owner's Manual

5. Reinstall the precleaner over the paper element.
6. Reinstall the air cleaner cover. Secure cover with
the cover retaining knob.
7. When precleaner replacement is necessary order
genuine Kohler parts. See chart below.
CH640 CH730
24 083 02-S 24 083 02-S 24 083 02-S 61 mm (2.4 in.)
- 24 083 05-S 24 083 05-S 71 mm (2.8 in.)
Service Paper Element
Every 100 hours of operation (more oft en under
extremely dusty or dirty conditions) replace the paper
element.
1. Loosen the cover retaining knob and remove the
air cleaner cover.
2. Remove the element cover nut, element cover,
and paper element/precleaner.
3. Remove the precleaner (if so equipped) from the
paper element and service as instructed above.
4. Do not wash the paper element or use
pressurized air, as this will damage the element.
Replace a dirty, bent, or damaged element with
a genuine Kohler element. Handle new elements
carefully; do not use if the sealing surfaces are
bent or damaged.
5. When servicing the air cleaner, check the air
cleaner base. Make sure it is secured and not bent
or damaged. Also, check the element cover for
damage or improper fi t. Replace all damaged air
cleaner components.
NOTE: Before air cleaner reassembly make sure
rubber seal is in position around stud.
Inspect, making sure it is not damaged and
seals with the element cover.
6. Reinstall the paper element, precleaner, element
cover, element cover nut, and air cleaner cover.
Secure cover with cover retaining knob.
7. When element replacement is necessary order
genuine Kohler parts. See chart below.
CH640 CH730
24 083 08-S 47 083 03-S 24 083 08-S 66 mm (2.6 in.)
- 24 083 03-S 24 083 09-S 74 mm (2.9 in.)
Height of
CH740
Precleaner
Height
CH740
of Element
Clean Air Intake/Cooling Areas
To ensure proper cooling, make sure the fl ywheel
screen, cooling fi ns, and other external surfaces of the
engine are kept clean at all times.
Every 100 hours of operation (more oft en under
extremely dusty, dirty conditions), remove the blower
housing and other cooling shrouds. Clean the cooling
fi ns and external surfaces as necessary. Make sure the
cooling shrouds are reinstalled.
NOTE: Operating the engine with a blocked
fl ywheel screen, dirty or plugged cooling
fi ns, and/or cooling shrouds removed, will
cause engine damage due to overheating.

Ignition System

CH640 and CH730 engines are equipped with an
electronic CDI system. CH740 engines are equipped
with an electronic DSAI system. Other than
periodically checking/replacing the spark plugs, no
maintenance, timing, or adjustments are necessary or
possible with these systems.
NOTE: Engines with a DSAI system will have leads
located near the fuel regulator. Connect the
leads for NG and leave disconnected for
LPG.
In the event starting problems should occur which are
not corrected by replacing the spark plugs, see your
Kohler Engine Service Dealer for trouble analysis.

Check Spark Plugs

Every 100 hours of operation, remove the spark plugs,
check condition, and reset the gap or replace with
new plugs as necessary. Every 300 hours or annually
replace the spark plugs. Refer to the chart below for
replacement spark plugs. Equivalent alternate brand
plugs can also be used.
Kohler
Model Part No.
25 132 14-S
CH640
12 132 02-S
CH730
25 132 14-S
12 132 02-S
25 132 12-S
CH740
25 132 14-S
1. Before removing the spark plug, clean the area
around the base of the plug to keep dirt and
debris out of the engine.
2. Remove the plug and check its condition.
Replace the plug if worn or reuse is questionable.
Gap
Champion© mm (in.)
XC12YC 0.51 (0.020)
RC12YC 0.76 (0.030)
XC12YC 0.76 (0.030)
RC12YC 0.76 (0.030)
3071 0.76 (0.030)
XC12YC 0.76 (0.030)
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