Kohler Confidant ZT710/ZT720/ZT730/ZT740 Engines OEM Service & Repair Manual

1 16 690 01 Rev. E KohlerEngines.com Service Manual ZT710-ZT740 2 Safety 3 Maintenance 5 Speciﬁcations 13 Tools and Aids 16 Troubleshooting 20 Air Cleaner/Intake 22 Fuel System 35 Governor System 36 Lubrication System 38 Electrical System 44 Starter System 52 Emission Compliant Systems 55 Disassembly/Inspection and Service 67 Reassembly 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.

2 Safety 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 fires and severe burns. Do not fill fuel tank while engine is hot or running. Gasoline is extremely flammable and its vapors can explode if ignited. Store gasoline only in approved containers, in well ventilated, unoccupied buildings, away from sparks or flames. Spilled fuel could ignite if it comes in contact with hot parts or sparks from ignition. Never use gasoline as a cleaning agent. 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 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 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 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 Cleaning Solvents can cause severe injury or death. Use only in well ventilated areas away from ignition sources. Carburetor cleaners and solvents are extremely flammable. Follow cleaner manufacturer’s warnings and instructions on its proper and safe use. Never use gasoline as a cleaning agent. CAUTION Electrical Shock can cause injury. Do not touch wires while engine is running. CAUTION Damaging Crankshaft and Flywheel can cause personal injury. Using improper procedures can lead to broken fragments. Broken fragments could be thrown from engine. Always observe and use precautions and procedures when installing flywheel. WARNING Uncoiling Spring can cause severe injury. Wear safety goggles or face protection when servicing retractable starter. Retractable starters contain a powerful, recoil spring that is under tension. Always wear safety goggles when servicing retractable starters and carefully follow instructions in Retractable Starter for relieving spring tension. KohlerEngines.com 16 690 01 Rev. E

3 Maintenance 16 690 01 Rev. E 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. MAINTENANCE SCHEDULE Every 25 Hours¹ ● Service/replace precleaner. Air Cleaner/Intake ● Replace air cleaner element (if not equipped with precleaner). Air Cleaner/Intake Every 100 Hours¹ ● Replace air cleaner element (if equipped with precleaner). Air Cleaner/Intake ● Change oil and filter. Lubrication System ● Remove cooling shrouds and clean cooling areas. Air Cleaner/Intake Every 100 Hours ● Check that all fasteners are in place and components are properly secured. Reassembly ● Replace fuel filter. Every 500 Hours² ● Have valve clearance (lash) checked/adjusted. Reassembly Every 500 Hours ● Replace spark plugs and set gap. Electrical System ¹ Perform these procedures more frequently under severe, dusty, dirty conditions. ² Have a Kohler authorized dealer perform this service. REPAIRS/SERVICE PARTS Kohler genuine service parts can be purchased from Kohler authorized dealers. To find a local Kohler authorized dealer visit KohlerEngines.com or call 1-800-544-2444 (U.S. and Canada).

4 Maintenance KohlerEngines.com 16 690 01 Rev. E 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 0 20 32 40 60 50 80 100 °C -30 -20 -10 0 10 20 30 40 5W-30 10W-30 SAE 30 FUEL RECOMMENDATIONS WARNING Explosive Fuel can cause fires and severe burns. Do not fill fuel tank while engine is hot or running. Gasoline is extremely flammable and its vapors can explode if ignited. Store gasoline only in approved containers, in well ventilated, unoccupied buildings, away from sparks or flames. 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 overfill fuel tank. ● Do not use gasoline older than 30 days. 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.

5 Speciﬁcations 16 690 01 Rev. E KohlerEngines.com Dimensions in millimeters. Inch equivalents shown in [ ]. Engine Dimensions with Low-Proﬁle Air Cleaner 4X Ø 9.005 ± 0.035 [.355 ± .0014] 254.00 B.C. [10.000] 37.00 [1.46]

6 Speciﬁcations KohlerEngines.com 16 690 01 Rev. E 37.00 [1.46] 4X Ø 9.005 ± 0.035 [.355 ± .0014] 254.00 B.C. [10.000] Dimensions in millimeters. Inch equivalents shown in [ ]. Engine Dimensions with Heavy-Duty Air Cleaner

7 Specifications 16 690 01 Rev. E KohlerEngines.com GENERAL SPECIFICATIONS 3,6 ZT710 ZT720 ZT730 ZT740 Bore 83 mm (3.27 in.) Stroke 67 mm (2.64 in.) 69 mm (2.72 in.) Displacement 725 cc (44 cu. in.) 747 cc (46 cu. in.) Oil Capacity (refill) 1.6-1.8 L (1.9-2.1 qt.) Maximum Angle of Operation (@ full oil level) 4 25° TORQUE SPECIFICATIONS 3,5 ZT710 ZT720 ZT730 ZT740 Auto Choke eChoke ™ Stepper Motor to Bracket Fastener Air Cleaner Base to Mounting Studs 3.1 N·m (27.4 in. lb.) 6.2-7.3 N·m (55-65 in. lb.) Baffle and Sheet Metal into Aluminum M5 Thread Forming Fasteners 8.5 N·m (75 in. lb.) into new hole 4.0 N·m (35 in. lb.) into used hole M6 Thread Forming Fasteners 10.7 N·m (95 in. lb.) into new hole 7.3 N·m (65 in. lb.) into used hole Blower Housing and Sheet Metal M3 HI-LO Screw 2.3 N·m (20 in. lb.) M4 HI-LO Screw 2.8 N·m (25 in. lb.) M5 Thread Forming Fasteners 3.4 N·m (30 in. lb.) Carburetor Mounting Nut 6.2-7.3 N·m (55-65 in. lb.) Connecting Rod Cap Fastener (torque in increments) Black Coating Gray Metallic Coating 11.3 N·m (100 in. lb.) 13.6 N·m (120 in. lb.) ENGINE IDENTIFICATION NUMBERS Kohler engine identification numbers (model, specification and serial) should be referenced for efficient repair, ordering correct parts, and engine replacement. Model . . . . . . . . . . . . . . . . . . . . . ZT710 Confidant Engine Numerical Designation Specification . . . . . . . . . . . . . . . ZT710-0001 Serial . . . . . . . . . . . . . . . . . . . . . 4423500328 Year Manufactured Code Factory Code Code Year 44 2014 45 2015 46 2016 3 Values are in Metric units. Values in parentheses are English equivalents. 4 Exceeding maximum angle of operation may cause engine damage from insufficient lubrication. 5 Lubricate threads with engine oil prior to assembly. 6 Any and all horsepower (hp) references by Kohler are Certified Power Ratings and per SAE J1940 & J1995 hp standards. Details on Certified Power Ratings can be found at KohlerEngines.com.

8 Specifications KohlerEngines.com 16 690 01 Rev. E TORQUE SPECIFICATIONS 3,5 ZT710 ZT720 ZT730 ZT740 Crankcase Breather Assembly Breather Reed Cover Stud Breather Reed Cover Hex Nut Breather Cover Fastener 6.2 N·m (55 in. lb.) into new hole 4.0 N·m (35 in. lb.) into used hole 1.3 N·m (12 in. lb.) 8.5 N·m (75 in. lb.) into new hole 4.0 N·m (35 in. lb.) into used hole Oil Drain Plug 13.6 N·m (10 ft. lb.) Cylinder Head Head Bolt Fastener (torque in 2 increments) first to 22.6 N·m (200 in. lb.) finally to 41.8 N·m (370 in. lb.) Rocker Arm Stud 11.3 N·m (100 in. lb.) Rocker Arm Adjuster Setscrew 7.9 N·m (70 in. lb.) Flywheel Retaining Screw 74.5 N·m (55 ft. lb.) Fuel Pump Screw 2.8 N·m (25 in. lb.) Governor Lever Nut 6.8 N·m (60 in. lb.) Ignition Spark Plug 27 N·m (20 ft. lb.) Module Fastener 4.0-6.2 N·m (35-55 in. lb.) Rectifier-Regulator Fastener 4.0 N·m (35 in. lb.) Intake Manifold Mounting Fastener (torque in 2 increments) first to 7.4 N·m (66 in. lb.) finally to 9.9 N·m (88 in. lb.) Muffler M8 Hex Nuts 24.4 N·m (216 in. lb.) 5/16-18 Capscrew 16.9 N·m (150 in. lb.) Bracket Screw 9.9 N·m (88 in. lb.) Oil Pan Fastener 24.4 N·m (216 in. lb.) Oil Pump Screw (no torque sequence) 9.9 N·m (88 in. lb.) Oil Sentry ™ Pressure Switch 4.5 N·m (40 in. lb.) 3 Values are in Metric units. Values in parentheses are English equivalents. 5 Lubricate threads with engine oil prior to assembly.

9 Speciﬁcations 16 690 01 Rev. E KohlerEngines.com TORQUE SPECIFICATIONS 3,5 ZT710 ZT720 ZT730 ZT740 Retractable Starter Mounting Screw 7.3 N·m (65 in. lb.) Center Screw 5.0-6.0 N·m (44-54 in. lb.) Solenoid (Starter) Mounting Hardware 4.0-6.0 N·m (35-53 in. lb.) Nut, Positive (+) Brush Lead 8.0-11.0 N·m (71-97 in. lb.) Speed Control Bracket Fastener 10.7 N·m (95 in. lb.) into new holes 7.3 N·m (65 in. lb.) into used holes Starter Assembly Thru Bolt Inertia Drive Solenoid Shift 4.5-5.7 N·m (40-50 in. lb.) 5.6-9.0 N·m (49-79 in. lb.) Mounting Screw 23.8 N·m (211 in. lb.) Brush Holder Mounting Screw 2.5-3.3 N·m (22-29 in. lb.) Stator Mounting Screw 8.8 N·m (78 in. lb.) Valve Cover Fastener 9.6 N·m (85 in. lb.) CLEARANCE SPECIFICATIONS 3 ZT710 ZT720 ZT730 ZT740 Camshaft End Play 0.06/0.40 mm (0.0024/0.0157 in.) Running Clearance 0.040/0.077 mm (0.0016/0.0030 in.) Bore I.D. New Max. Wear Limit 20.000/20.025 mm (0.7874/0.7884 in.) 20.038 mm (0.7889 in.) Bearing Surface O.D. New Max. Wear Limit 19.948/19.960 mm (0.7854/0.7858 in.) 19.945 mm (0.7852 in.) Connecting Rod Connecting Rod-to-Crankpin Running Clearance New Max. Wear Limit 0.037/0.083 mm (0.0015/0.0033 in.) 0.098 mm (0.0039 in.) Connecting Rod-to-Crankpin Side Clearance 0.261/0.67 mm (0.0102/0.0264 in.) Connecting Rod-to-Piston Pin Running Clearance 0.013/0.032 mm (0.0005/0.0013 in.) Piston Pin End I.D. New Max. Wear Limit 17.013/17.027 mm (0.6698/0.6704 in.) 17.040 mm (0.6709 in.) Crankcase Governor Cross Shaft Bore I.D. New Max. Wear Limit 8.025/8.075 mm (0.3159/0.3179 in.) 8.088 mm (0.3184 in.) 3 Values are in Metric units. Values in parentheses are English equivalents. 5 Lubricate threads with engine oil prior to assembly.

10 Speciﬁcations KohlerEngines.com 16 690 01 Rev. E CLEARANCE SPECIFICATIONS 3 ZT710 ZT720 ZT730 ZT740 Crankshaft End Play (free) 0.075/0.595 mm (0.0030/0.023 in.) Bore (in crankcase) New Max. Wear Limit 40.974/40.987 mm (1.6131/1.6137 in.) 41.000 mm (1.6142 in.) Bore (in oil pan) New 40.974/41.000 mm (1.6131/1.6142 in.) Crankshaft Bore (in oil pan)-to-Crankshaft Running Clearance New 0.039/0.087 mm (0.0015/0.0034 in.) Flywheel End Main Bearing Journal O.D. - New O.D. - Max. Wear Limit Max. Taper Max. Out-of-Round 40.913/40.935 mm (1.6107/1.6116 in.) 40.840 mm (1.608 in.) 0.022 mm (0.0009 in.) 0.025 mm (0.0010 in.) Oil Pan End Main Bearing Journal O.D. - New O.D. - Max. Wear Limit Max. Taper Max. Out-of-Round 40.913/40.935 mm (1.6107/1.6116 in.) 40.840 mm (1.608 in.) 0.022 mm (0.0009 in.) 0.025 mm (0.0010 in.) Connecting Rod Journal O.D. - New O.D. - Max. Wear Limit Max. Taper Max. Out-of-Round 35.950/35.974 mm (1.4154/1.4163 in.) 35.950 mm (1.4154 in.) 0.018 mm (0.0007 in.) 0.025 mm (0.0010 in.) T.I.R. PTO End, Crank in Engine Entire Crank, in V-Blocks 0.279 mm (0.0110 in.) 0.200 mm (0.0079 in.) Cylinder Bore Bore I.D. New Max. Wear Limit Max. Out-of-Round Max. Taper 83.006/83.031 mm (3.2679 in./3.2689 in.) 83.069 mm (3.2704 in.) 0.120 mm (0.0047 in.) 0.050 mm (0.0020 in.) Cylinder Head Max. Out-of-Flatness 0.076 mm (0.003 in.) Governor Governor Cross Shaft-to-Crankcase Running Clearance 0.025/0.126 mm (0.0009/0.0049 in.) Cross Shaft O.D. New Max. Wear Limit 7.949/8.000 mm (0.3129/0.3149 in.) 7.936 mm (0.3124 in.) Governor Gear Shaft-to-Governor Running Clearance 0.050/0.210 mm (0.0020/0.0083 in.) Gear Shaft O.D. New Max. Wear Limit 5.990/6.000 mm (0.2358/0.2362 in.) 5.977 mm (0.2353 in.) Ignition Spark Plug Gap 0.76 mm (0.030 in.) Module Air Gap 0.203/0.305 mm (0.008/0.012 in.) 3 Values are in Metric units. Values in parentheses are English equivalents.

Kohler Confidant ZT710/ZT720/ZT730/ZT740 Engines OEM Service & Repair Manual

You're Reading a Preview

Recently Viewed