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Part IV Wiring Diagram

 

16 

3-3 Disassembly chart 

 

 

 

3-4 Gasoline engine 

3-4-1 Air director 

 

 

 

 

Gasoline engine 

Air filter 

Carburetor 

Starting control box 

Air director 

Flywheel 

Ignition coil 

First twist out the 
locking handle 
assembly. 

Lift the fan guard 
decoration sheet 
up to take out it. 

Air director 

Air director 
plate 

Cross recessed 
pan head screw 

Acorn nut M6

 

Engine 

Summary of Contents for R740

Page 1: ...R740 Service Manual Chongqing RATO Technology Co Ltd...

Page 2: ...at any time This Manual describes correct methods to service this equipment The Company does not undertake any liability for any personal casualty and equipment damage caused due to ignoring these rul...

Page 3: ...l and on the decals of the generator sets There is the symbol in front of each safety warning Details are as follows Failure to follow instructions will lead to extremely serious injuries Failure to f...

Page 4: ...t judgement 10 3 1 1 Start difficulty 10 3 1 2 Underpower 11 3 1 3 Unstable speed 12 3 1 4 Unable to ignite 12 3 1 5 Overheating of general purpose gasoline engine 13 3 1 6 Abnormal sound 13 3 1 7 Fai...

Page 5: ...Disassembly and assembly 32 3 4 7 Starting control box 39 3 4 8 Starter motor 43 3 5 Electrical schematic diagram electric starting type 44 Appendix 45...

Page 6: ...Introduction 1 Part I Introduction 1 1 Engine components 1 1 1 Structural features Muffler Air filter Starting control box Radiator Fuel drain bolt Governing bracket Starter motor Spark plug Oil level...

Page 7: ...tactless Fuel tank volume L None Minimum fuel consumption rate g kw h 374 Oil capacity L 1 6L No load speed 3800 Rated output power kW 15 Maximum output power kW 16 8 Big air filter Big muffler Big oi...

Page 8: ...mm Connecting rod Inner diameter of small end Inner diameter of big end Big end oil film clearance Small end side clearance 17 005 17 016mm 40 01 40 022mm 0 03 0 054mm 0 2 0 6mm 17 052mm 40 066mm 0 12...

Page 9: ...he maintenance shall be carried out according to the time shown in the table above for the spot inspection period and time If the maintenance interval has expired the maintenance shall be carried out...

Page 10: ...cancer Although this is not certain it is still recommended to avoid direct contact as much as possible In case of contact wash the skin that has been exposed to oil with soap and water immediately a...

Page 11: ...er and dry it thoroughly Or wash it in non flammable solvent and dry it Do not make the foam stained with oil Paper filter element place the filter element on a hard surface gently fold it for several...

Page 12: ...ghtened after pressing the washer If a used spark plug is reinstalled an additional 1 8 1 4 turn shall be tightened after pressing the washer Spark plug torque value 22 2 N m 2 5 Adjustment of valve c...

Page 13: ...xhaust 0 15 0 02mm Adjusting screw Valve clearance Tighten Decrease Loosen Increase Too large clearance Late opening of intake and exhaust valves shortens the intake and exhaust time reduces the valve...

Page 14: ...hen rotating the governing arm shaft counterclockwise tighten the governing arm nut 5 Move the governor arm to the low speed position and check whether the throttle arm is in contact with the throttle...

Page 15: ...deposit Insulator is damaged electrode is severe ablated Replace the spark plug Electrode clearance is incorrect Adjust electrode clearance HV wire has no spark Spark plug is normal HV wire is damaged...

Page 16: ...readed part of spark plug via the cylinder cover pull the starter handle to observe the spark condition 3 1 2 Underpower Phenomenon Cause Remedy When raising the throttle the speed increases slowly an...

Page 17: ...asoline engine There is water in float chamber Clean the float chamber Electrode clearance of spark plug is improper Adjust electrode clearance Ignition coil failure etc Check and replace damaged part...

Page 18: ...ise generates during deflagration Excessive carbon deposit in combustion chamber Clear carbon deposit Fuel label is incorrect Replace fuel Gasoline engine overheating Find the cause and eliminate Othe...

Page 19: ...ate emergency shut down and all control components Adhere to regular maintenance and service and eliminate the fault found in time and prohibit continuous operation of the engine after the failure 7 W...

Page 20: ...ller Valve guide reamer Inspection of oil level of the carburetor Disassembly and installation of valve guide Assembly of the ball bearing Installation of the handle on the assembler and installation...

Page 21: ...ector Gasoline engine Air filter Carburetor Starting control box Air director Flywheel Ignition coil First twist out the locking handle assembly Lift the fan guard decoration sheet up to take out it A...

Page 22: ...mage and in severe cases it may cause casualties 1 Impeller Please align the lug behind the impeller with the hole on the flywheel during installation 2 Flywheel Remove the ignition coil and the charg...

Page 23: ...detection wire to the primary terminal of the ignition coil and make the other detection wire contact with the iron core and then measure the resistance of the primary coil Resistance value on the pri...

Page 24: ...sert a plug gauge between the ignition coil and the flywheel and adjust the ignition coil position 3 After adjustment pre tighten the bolt check the clearance again and then tighten the bolt and apply...

Page 25: ...carburetor At high altitude areas standardized carburetor will cause thick mixed gas drop the output power and increase the fuel consumption rate for the gasoline engine Gasoline engine used at high...

Page 26: ...elatinous substance which will condense gelatinous substance after a long time of deposition to attach to components of the carburetor such as main metering hole oil way and the surface of float chamb...

Page 27: ...e bolts please tighten the bolts according to the torque table b Replacement of altitude kit Disassembly and assembly of carburetor Turn the carburetor upside down and use a cross screwdriver to unscr...

Page 28: ...unscrew the main nozzle to the right For replacement of main nozzles both main nozzles should be replaced When disassembling the main nozzles please place the carburetor in the same direction as the a...

Page 29: ...n Flames a Before assembly check the wear of the float valve the float valve seat and the float spring Float valve Float valve seat Idle metering hole O ring Adjusting screw of mixing ratio Carburetor...

Page 30: ...When the float valve just touches the float seat and the spring is not compressed measure the distance between the top of the float valve and the carburetor body Specified float height 23mm In case of...

Page 31: ...out disassembly from top to bottom Air director of cylinder block Cylinder head bolt Bolt M6 10 Cylinder head cover bolt Valve lifter assembly Sealing ring Cylinder head cover Cylinder head cover bolt...

Page 32: ...er the spring retainer may fall into the crankcase which should be noted Outer diameter of valve stem Use a micrometer to check the outside diameter of valve stem If the diameter is lower than standar...

Page 33: ...e measuring the inner diameter of the valve guide pipe remove carbon depositinside valve guide pipe by valve guide reamer If the inner diameter of the valve guide pipe is below the standard or exceeds...

Page 34: ...valve guide Screw into the reamer clockwise until the reamer is fully screwed into the air valve guide pipe Continue to rotate clockwise to pull out the valve reamer from the valve guide Tool valve g...

Page 35: ...e wiped b Insert the valve and press the valve with effort a few times but do not rotate the valveon the valve seat If the valve seat is stained with paint it indicates that it is in close contact wit...

Page 36: ...s shown in the figure it means that the valve is in good contact with the valve seat cone face g Apply abrasive to valve seat cone surface and rotate valve grinding tool to grind the valve seat h Chec...

Page 37: ...Appendix 32 Disassembly and assembly Crankcase assembly Crankcase gasket Locating pin Crankcase cover assembly Oil seal Bolt M8 50 Bolt M8 55...

Page 38: ...assembly Oil screen Crankcase cover Steel ball Pressure relief valve spring Governing gear components Oil level gauge assembly Oil pump components Locating pin Bolt M6 20 Oil suction pipe Bolt M6 25 O...

Page 39: ...bolt Flat washer Oil sensor Bolt M6 20 Bolt M6 20 Bolt M6 30 Tension disc Breathing tank gasket Breathing tank gasket Breathing plate assembly Breathing tank screen Negative pressure nozzle Governing...

Page 40: ...g moves freely after assembling Make openings of various piston rings keep away from the direction of piston pin and scatter by 120 Connecting rod Assembly Make longer side of big end part be toward m...

Page 41: ...on the top of piston and the edge of upper port of the cylinder Carbon deposits shall be cleared up before the inspection Soak the carbon deposit with kerosene first and then remove it with a blunt sc...

Page 42: ...side During inspection place each ring in its respective piston ring groove Piston rings shall rotate freely to be neither loose nor sluggish Then measure by inserting a thickness gauge into the clea...

Page 43: ...aced Standard Service limit 40 022mm 40 066mm Inspection of camshaft The camshaft is main driving part of valve train of gasoline engine which controls intake and exhaust valves to open or close Its s...

Page 44: ...camshaft journal and camshaft seat or bearing is out of tolerance rotation accuracy of the camshaft will decrease and the contact with related parts will generate deviation plane t cause abnormal wear...

Page 45: ...ut Oil alarm device Assembly Carry out installation by aligning the hole of the control panel Control panel Reset switch 1A Assembly Be careful not to invert the left side and the right side Combinati...

Page 46: ...eck the conduction performance between the black wire and the gasoline engine switch body Position of the gasoline engine switch Conduction ON Non conduction OFF Conduction Combination switch with aut...

Page 47: ...low wires of the oil alarm device 6V battery or dry battery make sure that the alarm indicator is on Black red of the battery Yellow of the battery Never use batteries above 6V Otherwise the bulb will...

Page 48: ...ps to disassemble the starting control box first Installation During installation the opening faces the electromagnetic switch side Tighten the wires of the oil level switch and the fuel cut off solen...

Page 49: ...ite Voltage regulator Red White Yellow Yellow Deep green and deep yellow Yellow Green Battery Flywheel charging coil Spark plug ignition coil Carburetor coil Spark plug ignition coil Starter motor Red...

Page 50: ...10 2 Oil sensor assembly M6 16 9 1 Pressure sensor assembly 1 8 20 2 Muffler assembly M8 20 2 Governing bracket assembly M6 11 1 Other commonly used bolts M6 10 2 Other commonly used nuts M6 10 2 Oth...

Page 51: ...d Address Area B Shuangfu Industrial Park Jiangjin District Chongqing Service hotline 400 681 9981 Fax 023 85553450 Postal code 402247 Website www rato cc E mail ratoservice rato cc service consultati...

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