Kohler Command Pro CV980 - Manual (Page 34)

5.6
Section 5
Fuel System and Governor
Lean
Rich
Adjust to
Midpoint
Lean
Rich
Adjust to
Midpoint
Left Side Right Side
Carburetor Adjustments
Adjustment
DZȱ Š›‹ž›Ž˜›ȱŠ“žœ–Ž—œȱœ‘˜ž•ȱ‹Žȱ–ŠŽȱ˜—•¢ȱ
ŠĞŽ›ȱ‘ŽȱŽ—’—Žȱ‘Šœȱ Š›–Žȱž™ǯ
The carburetor is designed to deliver the correct
fuel-to-air mixture to the engine under all operating
conditions. The main fuel jet is calibrated at the
factory and is not adjustable*. The idle fuel adjusting
needle is also set at the factory and normally does not
need adjustment.
ȘDZȱ —’—Žœȱ˜™Ž›Š’—ȱŠȱŠ•’žŽœȱŠ‹˜ŸŽȱ
Š™™›˜¡’–ŠŽ•¢ȱŗśŖŖȱ–ȱǻśŖŖŖȱĞǯǼȱ–Š¢ȱ
require a special ‘‘high altitude’’ main
“ŽǯȱŽŽ›ȱ˜ȱȁȁ’‘ȱ•’žŽȱ™Ž›Š’˜—ȂȂȱ
later in this section.
If, however, the engine is hard-starting or does not
operate properly, it may be necessary to adjust or
service the carburetor.
Low Idle Speed (RPM) Adjustment
1. ˜ ȱ•Žȱ™ŽŽȱǻǼȱŽĴ’—DZȱ•ŠŒŽȱ‘Žȱ‘›˜Ĵ•Žȱ
control in the “idleȄȱ˜›ȱȃslowȄȱ™˜œ’’˜—ǯȱŽȱ‘Žȱ
low idle speed approximately 300 RPM less than
‘Žȱ’—Ž—Žȱ˜›ȱœ™ŽŒ’ꮍȱ ˜ŸŽ›—Žȱ•Žȱ™ŽŽǰȱ
by turning the low idle speed adjusting screw
in or out. Check the speed using a tachometer.
IMPORTANT: The Governed Idle Speed
“žœ–Ž—ȱ–žœȱ˜••˜ ȱŠ—¢ȱ›ŽœŽĴ’—ȱ˜ȱ‘Žȱ
Low Idle Speed.
ȘDZȱ ‘ŽȱŠŒžŠ•ȱ•˜ ȱ’•Žȱœ™ŽŽȱŽ™Ž—œȱ˜—ȱ
the application. Refer to the equipment
manufacturer’s recommendations.
The low idle speed for basic engines is
1200 RPM. To ensure best results when
œŽĴ’—ȱ‘Žȱ•˜ ȱ’•ŽȱžŽ•ȱ—ŽŽ•Žǰȱ‘Žȱ•˜ ȱ
idle speed should be 1200 RPM (± 75
RPM).
Figure 5-5. Carburetor Adjustment Locations.
Low Idle Fuel Adjustment
DZȱ —’—Žœȱ ’••ȱ‘ŠŸŽȱę¡Žȱ•˜ ȱ’•Žȱ˜›ȱ•’–’Ž›ȱ
caps on the two idle fuel adjusting needles.
Step 3 can only be performed within the
•’–’œȱŠ••˜ Žȱ‹¢ȱ‘ŽȱŒŠ™ǯȱ˜ȱ—˜ȱŠĴŽ–™ȱ˜ȱ
remove the limiter caps.
ȱ ŗǯȱ Š›ȱ‘ŽȱŽ—’—ŽȱŠ—ȱ›ž—ȱŠȱ‘Š•ȱ‘›˜Ĵ•Žȱ˜›ȱśȱ˜ȱŗŖȱ
minutes to warm up. The engine must be warm
‹Ž˜›Žȱ˜’—ȱœŽ™œȱŘǰȱřǰȱŠ—ȱŚǯ
ȱŘǯȱ •ŠŒŽȱ‘Žȱ‘›˜Ĵ•ŽȱŒ˜—›˜•ȱ’—˜ȱ‘Žȱȃ’•ŽȄȱ˜›ȱȃœ•˜ Ȅȱ
™˜œ’’˜—ǯȱ“žœȱ‘Žȱ•˜ ȱ’•Žȱœ™ŽŽȱ˜ȱŗŘŖŖȱ
ǯȱ˜••˜ ȱ‘Žȱȃ“žœ’—ȱ‘Žȱ˜ ȱ•Žȱ™ŽŽȱ
ǻǼȄȱ™›˜ŒŽž›Žǯ
3.ȱ ˜ ȱ•ŽȱžŽ•ȱŽŽ•ŽǻœǼȱŽĴ’—DZ Place the
‘›˜Ĵ•Žȱ’—˜ȱ‘Žȱȃ’•ŽȄȱ˜›ȱȃœ•˜ Ȅȱ™˜œ’’˜—ǯ
a. Turn one of the low idle fuel adjusting
needles out (counterclockwise) from the
™›Ž•’–’—Š›¢ȱœŽĴ’—ȱž—’•ȱ‘ŽȱŽ—’—Žȱœ™ŽŽȱ
decreases (rich). Note the position of the
needle. Now turn the adjusting needle in
(clockwise). The engine speed may increase,
then it will decrease as the needle is turned
in (lean). Note the position of the needle. Set
the adjusting needle midway between the
›’Œ‘ȱŠ—ȱ•ŽŠ—ȱœŽĴ’—œǯȱŽŽȱ’ž›ŽȱśȬŜǯ
b. Repeat the procedure on the other
low idle adjustment needle.
ȱ Śǯȱ ŽŒ‘ŽŒ”ȦŠ“žœȱ‘Žȱ˜ ȱ•Žȱ™ŽŽȱǻǼǰȱ˜ȱ‘Žȱ
œ™ŽŒ’ꮍȱœŽĴ’—ǯ
Figure 5-6. Optimum Low Idle Fuel Settings.
Low Idle
Speed
(RPM)
Adjustment
Screw
Low Idle Fuel
Adjustments
(With Limiters)
Bowl
Vent