1. 24 590 27 Rev. A KohlerEngines.com CH18-CH23, CH620-CH740, CH750 Owner's Manual IMPORTANT: Read all safety precautions and instructions carefully before operating equipment. Refer to operating instruction of equipment that this engine powers. Ensure engine is stopped and level before performing any maintenance or service. Warranty coverage as outlined in the warranty card and on KohlerEngines.com. Please review carefully as it provides you speci fi c rights and obligations. Record engine information to reference when ordering parts or obtaining warranty coverage. Engine Model Speci fi cation Serial Number Purchase Date CV18-CV23, CV620-CV740, CV750

2. 2 24 590 27 Rev. A KohlerEngines.com Safety Precautions WARNING: A hazard that could result in death, serious injury, or substantial property damage. CAUTION: A hazard that could result in minor personal injury or property damage. NOTE: is used to notify people of important installation, operation, or maintenance information. WARNING Explosive Fuel can cause fi res and severe burns. Do not fi ll fuel tank while engine is hot or running. Gasoline is extremely fl ammable and its vapors can explode if ignited. Store gasoline only in approved containers, in well ventilated, unoccupied buildings, away from sparks or fl ames. Spilled fuel could ignite if it comes in contact with hot parts or sparks from ignition. Never use gasoline as a cleaning agent. WARNING Hot Parts can cause severe burns. Do not touch engine while operating or just after stopping. Never operate engine with heat shields or guards removed. WARNING Rotating Parts can cause severe injury. Stay away while engine is in operation. Keep hands, feet, hair, and clothing away from all moving parts to prevent injury. Never operate engine with covers, shrouds, or guards removed. WARNING Accidental Starts can cause severe injury or death. Disconnect and ground spark plug lead(s) before servicing. Before working on engine or equipment, disable engine as follows: 1) Disconnect spark plug lead(s). 2) Disconnect negative (–) battery cable from battery. WARNING Carbon Monoxide can cause severe nausea, fainting or death. Avoid inhaling exhaust fumes. Engine exhaust gases contain poisonous carbon monoxide. Carbon monoxide is odorless, colorless, and can cause death if inhaled. CAUTION Electrical Shock can cause injury. Do not touch wires while engine is running. California Proposition 65 Warning Engine exhaust from this product contains chemicals known to State of California to cause cancer, birth defects, or other reproductive harm.

4. 4 24 590 27 Rev. A KohlerEngines.com Starting WARNING Carbon Monoxide can cause severe nausea, fainting or death. Avoid inhaling exhaust fumes. Engine exhaust gases contain poisonous carbon monoxide. Carbon monoxide is odorless, colorless, and can cause death if inhaled. WARNING Rotating Parts can cause severe injury. Stay away while engine is in operation. Keep hands, feet, hair, and clothing away from all moving parts to prevent injury. Never operate engine with covers, shrouds, or guards removed. NOTE: Do not crank engine continuously for more than 10 seconds. Allow a 60 second cool down period between starting attempts. Failure to follow these guidelines can burn out starter motor. NOTE: Upon start-up, a metallic ticking may occur. Run engine for 5 minutes. If noise continues, run engine at mid throttle for 20 minutes. If noise persists, take engine to your local Kohler authorized dealer. 1. Place throttle control midway between slow and fast positions. Place choke control into ON position. 2. Turn key switch to START position. Release switch as soon as engine starts. If starter does not turn engine over, shut off key switch immediately. Do not make further attempts to start engine until condition is corrected. Do not jump start. See your Kohler authorized dealer for trouble analysis. 3. Cold engine: Gradually return choke control to OFF position after engine starts and warms up. Engine/equipment may be operated during warm-up period, but it may be necessary to leave choke partially on until engine warms up. Warm engine: return choke to OFF position as soon as engine starts. Cold Weather Starting Hints 1. Use proper oil for temperature expected. 2. Disengage all possible external loads. 3. Use fresh winter grade fuel. Winter grade fuel has higher volatility to improve starting. Stopping 1. If possible, remove load by disengaging all PTO driven attachments. 2. Position throttle control between half and full throttle; stop engine. Angle of Operation Refer to operating instructions of equipment this engine powers. Do not operate this engine exceeding maximum angle of operation; see speci fi cation table. Engine damage could result from insuf fi cient lubrication. Engine Speed NOTE: Do not tamper with governor setting to increase maximum engine speed. Overspeed is hazardous and will void warranty. Cold Weather Operation Anti-icing kits can be installed to improve cold weather operation and are available through your local Kohler authorized dealer. High Altitude Operation This engine may require a high altitude carburetor kit to ensure correct engine operation at altitudes above 4000 ft. (1219 meters). To obtain high altitude kit information or to fi nd a Kohler authorized dealer visit KohlerEngines.com or call 1-800-544-2444 (U.S. and Canada). This engine should be operated in its original con fi guration below 4000 ft. (1219 meters) as damage may occur if high altitude carburetor kit is installed and operated below 4000 ft. (1219 meters).

7. 7 24 590 27 Rev. A KohlerEngines.com 4. Check all parts for wear, cracks, or damage, and that ejector area is clean. 5. Install new element(s). 6. Reinstall end cap(s) with dust ejector valve/ screen down; secure with retaining clips. Breather Tube Ensure both ends of breather tube are properly connected. Oil Cooler (if equipped) 1. Clean fi ns with a brush or compressed air. 2. Remove two screws securing oil cooler, and tilt to clean back side. 3. Reinstall oil cooler. Air Cooling WARNING Hot Parts can cause severe burns. Do not touch engine while operating or just after stopping. Never operate engine with heat shields or guards removed. Proper cooling is essential. To prevent over heating, clean screens, cooling fi ns, and other external surfaces of engine. Avoid spraying water at wiring harness or any electrical components. See Maintenance Schedule. Repairs/Service Parts We recommend that you use a Kohler authorized dealer for all maintenance, service, and replacement parts for engine. To fi nd a Kohler authorized dealer visit KohlerEngines.com or call 1-800-544-2444 (U.S. and Canada). Storage If engine will be out of service for 2 months or more follow procedure below. 1. Add Kohler PRO Series fuel treatment or equivalent to fuel tank. Run engine 2-3 minutes to get stabilized fuel into fuel system (failures due to untreated fuel are not warrantable). 2. Change oil while engine is still warm from operation. Remove spark plug(s) and pour about 1 oz. of engine oil into cylinder(s). Replace spark plug(s) and crank engine slowly to distribute oil. 3. Disconnect negative (-) battery cable. 4. Store engine in a clean, dry place. Spark Plugs CAUTION Electrical Shock can cause injury. Do not touch wires while engine is running. Clean out spark plug recess. Remove plug and replace. 1. Check gap using wire feeler gauge. Adjust gap, see speci fi cation table for adjustment. 2. Install plug into cylinder head. 3. Torque plug to 20 ft. lb. (27 N·m). Air Cleaner NOTE: Operating engine with loose or damaged air cleaner components could cause premature wear and failure. Replace all bent or damaged components. NOTE: Paper element cannot be blown out with compressed air. Low-Pro fi le/Commercial Mower Loosen knob and remove air cleaner cover. Precleaner: 1. Remove precleaner from paper element. 2. Replace or wash precleaner in warm water with detergent. Rinse and allow to air dry. 3. Saturate precleaner with new engine oil; squeeze out excess oil. 4. Reinstall precleaner over paper element. Paper Element: 1. Clean area around element. Remove wing nut, element cover, and paper element with precleaner. 2. Separate precleaner from element; service precleaner and replace paper element. 3. Check condition of rubber seal and replace if necessary. 4. Install new paper element on base; install precleaner over paper element; reinstall element cover and secure with wing nut. Reinstall air cleaner cover and secure with knob. Heavy-Duty 1. Unhook retaining clips and remove end cap(s). 2. Check and clean inlet screen (if equipped). 3. Pull air cleaner element out of housing and replace. Check condition of inner element; replace when dirty.

8. 24 590 27 Rev. A KohlerEngines.com Troubleshooting Do not attempt to service or replace major engine components, or any items that require special timing or adjustment procedures. This work should be performed by a Kohler authorized dealer. © 2011 by Kohler Co. All rights reserved. Possible Cause Problem No Fuel Improper Fuel Dirt In Fuel Line Dirty Debris Screen Incorrect Oil Level Engine Overloaded Dirty Air Cleaner Faulty Spark Plug Will Not Start ●●● ● ● ● ● Hard Starting ●● ●●●● Stops Suddenly ● ●●●●●● Lacks Power ●●●● ● ● ● Operates Erratically ●●● ● ● ● Knocks or Pings ●● ● ● Skips or Mis fi res ●●● ● ● Back fi res ●● ● ● ● Overheats ●●●● ● ● High Fuel Consumption ●●● Engine Speci fi cations Model Bore Stroke Displacement Oil Capacity (Re fi ll) Spark Plug Gap Maximum Angle of Operation (@ full oil level)* CH18/CH620 3.03 in. (77 mm) 2.6 in. (67 mm) 38.1 cu. in. (624 cc) 1.7-1.9 U.S. qt. (1.6-1.8 L) 0.03 in. (0.76 mm) 25° CV18/CV620 CH20/CH640 CV20/CV640 CH23/CH680 3.2 in. (80 mm) 41 cu. in. (674 cc) CH670 CV23/CV680 CV670 CH730 3.27 in. (83 mm) 44.2 cu. in. (725 cc) CV730 CH740 CV740 CH750 2.72 in. (69 mm) 45.6 cu. in. (747 cc) CV750 *Exceeding maximum angle of operation may cause engine damage from insuf fi cient lubrication. Additional speci fi cation information can be found in service manual at KohlerEngines.com. Exhaust Emission Control System for models CH18-CH23, CV18-CV23, CH620-CH740, CV620- CV740, CH750, and CV750 is EM for U.S. EPA, California, and Europe. Any and all horsepower (hp) references by Kohler are Certi fi ed Power Ratings and per SAE J1940 & J1995 hp standards. Details on Certi fi ed Power Ratings can be found at KohlerEngines.com.

5. 5 24 590 27 Rev. A KohlerEngines.com Maintenance Instructions WARNING Before working on engine or equipment, disable engine as follows: 1) Disconnect spark plug lead(s). 2) Disconnect negative (–) battery cable from battery. Accidental Starts can cause severe injury or death. Disconnect and ground spark plug lead(s) before servicing. Normal maintenance, replacement or repair of emission control devices and systems may be performed by any repair establishment or individual; however, warranty repairs must be performed by a Kohler authorized dealer found at KohlerEngines.com or 1-800-544-2444 (U.S. and Canada). Maintenance Schedule Weekly ● Check heavy-duty air cleaner element. Every 25 Hours or Annually 1 ● Service/replace low-pro fi le precleaner. Every 100 Hours or Annually 1 ● Replace low-pro fi le air cleaner element. ● Change oil. ● Remove cooling shrouds and clean cooling areas. ● Check oil cooler fi ns, clean as necessary (if equipped). Every 200 Hours ● Change oil fi lter. ● Replace fuel fi lter. Every 250 Hours 1 ● Replace heavy-duty air cleaner element and check inner element. Every 500 Hours 1 ● Replace heavy-duty air cleaner inner element. ● Replace spark plugs and set gap. Every 500 Hours 2 ● Have crankshaft spline lubricated. 1 Perform these procedures more frequently under severe, dusty, dirty conditions. 2 Have a Kohler authorized dealer perform this service. Oil Recommendations We recommend use of Kohler oils for best performance. Other high-quality detergent oils (including synthetic) of API (American Petroleum Institute) service class SJ or higher are acceptable. Select viscosity based on air temperature at time of operation as shown in table below. °F -20 020324060 50 80 100 °C -30 -20 -10 0 10 20 30 40 5W-30 10W-30 SAE 30 Check Oil Level NOTE: To prevent extensive engine wear or damage, never run engine with oil level below or above operating range indicator on dipstick. Ensure engine is cool. Clean oil fi ll/dipstick areas of any debris. 1. Remove dipstick; wipe oil off. a. Press-in cap: reinsert dipstick into tube; press completely down. or b. Thread-on cap: reinsert dipstick into tube; rest cap on tube, do not thread cap onto tube. 2. Remove dipstick; check oil level. Level should be at top of indicator on dipstick. 3. If oil is low on indicator, add oil up to top of indicator mark. 4. Reinstall dipstick and tighten securely.

6. 6 24 590 27 Rev. A KohlerEngines.com Fuel Recommendations WARNING Explosive Fuel can cause fi res and severe burns. Do not fi ll fuel tank while engine is hot or running. Gasoline is extremely fl ammable and its vapors can explode if ignited. Store gasoline only in approved containers, in well ventilated, unoccupied buildings, away from sparks or fl ames. Spilled fuel could ignite if it comes in contact with hot parts or sparks from ignition. Never use gasoline as a cleaning agent. NOTE: E15, E20 and E85 are NOT approved and should NOT be used; effects of old, stale or contaminated fuel are not warrantable. Fuel must meet these requirements: ● Clean, fresh, unleaded gasoline. ● Octane rating of 87 (R+M)/2 or higher. ● Research Octane Number (RON) 90 octane minimum. ● Gasoline up to 10% ethyl alcohol, 90% unleaded is acceptable. ● Methyl Tertiary Butyl Ether (MTBE) and unleaded gasoline blend (max 15% MTBE by volume) are approved. ● Do not add oil to gasoline. ● Do not over fi ll fuel tank. ● Do not use gasoline older than 30 days. Fuel Line Low permeation fuel line must be installed on carbureted Kohler Co. engines to maintain EPA and CARB regulatory compliance. Change Oil and Filter Change oil while engine is warm. 1. Clean area around oil fi ll cap/dipstick, drain plug/oil drain valve. a. Remove drain plug and oil fi ll cap/ dipstick. Allow oil to drain completely. or b. Open oil drain valve cap; if needed, attach a length of 1/2 in. I.D. hose to direct oil into appropriate container; twist valve drain body counterclockwise and pull. Remove dipstick. Allow oil to drain completely. 2. Clean area around oil fi lter. Place a container under fi lter to catch any oil and remove fi lter. Wipe off mounting surface. a. Reinstall drain plug. Torque to 10 ft. lb. (13.6 N·m). or b. Close oil drain valve body, remove hose (if used), and replace cap. 3. Place new fi lter in shallow pan with open end up. Fill with new oil until oil reaches bottom of threads. Allow 2 minutes for oil to be absorbed by fi lter material. 4. Apply a thin fi lm of clean oil to rubber gasket on new fi lter. 5. Refer to instructions on oil fi lter for proper installation. 6. Fill crankcase with new oil. Level should be at top of indicator on dipstick. 7. Reinstall oil fi ll cap/dipstick and tighten securely. 8. Start engine; check for oil leaks. Stop engine; correct leaks. Recheck oil level. 9. Dispose of used oil and fi lter in accordance with local ordinances. Oil Sentry ™ (if equipped) This switch is designed to prevent engine from starting in a low oil or no oil condition. Oil Sentry ™ may not shut down a running engine before damage occurs. In some applications this switch may activate a warning signal. Read your equipment manuals for more information.

3. 3 24 590 27 Rev. A KohlerEngines.com A Dipstick B Oil Fill C Fuel Filter D Oil Filter E Oil Cooler F Oil Drain Plug G Debris Screen H Dust Ejector Valve I Heavy-Duty Air Cleaner J End Cap K Element L Inner Element M Air Cleaner Housing N Inlet Screen O Retaining Clip P Ejector Area Q Air Cleaner Knob R Rubber Seal S Air Cleaner Cover T Wing Nut U Element Cover V Precleaner W Paper Element X Air Cleaner Base Y Low-Pro fi le Air Cleaner Z Oil Fill/Dipstick G I Pre-Start Checklist 1. Check oil level. Add oil if low. Do not over fi ll. 2. Check fuel level. Add fuel if low. Check fuel system components and lines for leaks. 3. Check and clean cooling areas, air intake areas and external surfaces of engine (particularly after storage). 4. Check that air cleaner components and all shrouds, equipment covers, and guards are in place and securely fastened. 5. Check spark arrestor (if equipped). E D B C F K Q S T U R V W X Z Y A H J N O M P L