Bosch PB-650 Service Manual
  1. Manuals
  2. Brands
  3. Bosch Manuals
  4. Blower
  5. PB-650
  6. Service manual
Bosch PB-650 Service Manual

Bosch PB-650 Service Manual

Hide thumbs
Table of Contents

Advertisement

Quick Links

Download this manual
REVISED JUNE 2004
Ord. No. 403-12

Advertisement

Table of Contents
loading

Related Manuals for Bosch PB-650

Summary of Contents for Bosch PB-650

  • Page 1 REVISED JUNE 2004 Ord. No. 403-12...
  • Page 2 INTRODUCTION This service manual contains information for service and maintenance of ECHO POWER BLOWER, model PB-650 (Serial Number up to 35999999) and PB-750 (Serial Number up to 35999999). For systematic diagnosis, to avoid extra work and time loss, please refer to “Troubleshooting guide”...

  • Page 3: Table Of Contents

    PB-650 PB-750 TABLE OF CONTENTS Page Page 1 SERVICE INFORMATION ........2 Removing handle .......... 26 Specifications ..........2 Replacing throttle wire and switch ....27 Technical data ..........3 Adjusting throttle control lever friction ..27 Torque limits ............ 4 Assembling handle ........

  • Page 4: Service Information

    PB-650 SERVICE INFORMATION PB-750 1 SERVICE INFORMATION 1-1 Specifications Model PB-650 PB-750 Dimensions Length* mm(in) 375 (14.8) Width* mm(in) 470 (18.5) Height* mm(in) 527 (20.8) Dry weight** kg(lb) 10.7 (23.6) 11.4 (25.1) Engine Type KIORITZ, air-cooled, two-stroke, single cylinder Rotation...

  • Page 5: Technical Data

    PB-650 PB-750 SERVICE INFORMATION 1-2 Technical data Model PB-650 PB-750 Engine Idling speed r/min 2200 - 2800 Wide open throttle speed r/min 7000 Compression pressure MPa (kgf/cm ) (psi) 0.8 (8.0) (115) Ignition system Spark plug gap mm(in) 0.6 - 0.7 (0.024 - 0.028)

  • Page 6: Torque Limits

    PB-650 SERVICE INFORMATION PB-750 1-3 Torque limits Descriptions Size kgf • cm N• m in• lbf Starter Starter pawl assembly M 10 80 - 100 8 - 10 70 - 90 system Starter case M 5*** 35 - 50 3.5 - 5.0...

  • Page 7: Special Repairing Materials

    PB-650 PB-750 SERVICE INFORMATION 1-4 Special repairing materials Material Location Remarks Grease Rewind spring Starter center post Lithium based grease Oil seal inner lips Thread locking sealant Ball bearing Loctite #675 or equivalent Muffler Loctite #242, ThreeBond #1327 or equivalent...

  • Page 8: Service Limits

    PB-650 SERVICE INFORMATION PB-750 1-5 Service limits 5K248 5K249 5K250 5K247 5K251 5K016 5K042 5K252 5K219 5K220 Description mm(in) Cylinder bore When plating is worn and aluminum can be seen Piston outer diameter Min. 47.95 (1.888) Piston pin bore Max.

  • Page 9: Special Tools

    PB-650 PB-750 SERVICE INFORMATION 1-6 Special tools 3: a = 4 4: a = 5 Part Number Description Used for: 897801-33330 Tachometer PET-1000 895115-00330 Magneto wrench 895610-79920 L-hex wrench (4 mm) 895611-79920 L-hex wrench (5 mm) 897501-03938 Puller 897537-30130 Piston stopper...

  • Page 10: Starter System

    PB-650 STARTER SYSTEM PB-750 2 STARTER SYSTEM ( A ) Pawl carrier ( B ) Starter pawl ( C ) Starter drum ( D ) Rewind spring ( E ) Starter case ( F ) Starter rope ( G ) Rope guide...

  • Page 11: Removing Starter Drum And Rope

    PB-650 STARTER SYSTEM PB-750 2-1 Removing starter drum and rope 1. Unscrew four bolts of starter case (A) to remove it from engine body. 2. Pull off the starter rope knot (B) in starter grip . 3. Cut off or untie the knot (B) and allow rope to slowly rewind by holding starter drum.

  • Page 12: Replacing Rope Guide

    PB-650 STARTER SYSTEM PB-750 2-2 Replacing rope guide If rope guide is worn out or damaged, replace it as follows: 1. Remove or break rope guide by prying from starter case with a screwdriver. 2. Push out remaining guide from case.

  • Page 13: Installing Starter Drum And Rope

    PB-650 STARTER SYSTEM PB-750 2-4 Installing starter drum and rope 1. When installing a new starter rope, singe both ends of rope to prevent fraying. WARNING DANGER Do not use flame in an area where gasoline is stored or flammable gases may exist.

  • Page 14: Increasing Rope Tension

    PB-650 STARTER SYSTEM PB-750 2-5 Increasing rope tension 1. Pre-tension spring by rotating starter drum counterclockwise 3 to 4 turns with rope hooked at the notch (A). 2. Hold starter drum to prevent it from rewinding, and pull on starter grip, to take up the rope slack.

  • Page 15: Ignition System

    PB-650 IGNITION SYSTEM PB-750 3 IGNITION SYSTEM ( A ) Spark plug ( B ) Spark plug cap coil ( C ) Spark plug cap ( D ) Flywheel ( E ) Ignition coil ( F ) Primary lead (G) Ignition switch...

  • Page 16: Testing Spark

    PB-650 IGNITION SYSTEM PB-750 3-2 Testing spark WARNING DANGER Do not touch the spark plug while perform- ing the test to avoid receiving electric shock. WARNING DANGER Do not check the spark in an area where gaso- 5K124 5K123 line is spilled or flammable gases may exist.

  • Page 17: Replacing Spark Plug Cap And Coil

    PB-650 IGNITION SYSTEM PB-750 3-4 Replacing spark plug cap and coil 1. Disconnect the spark plug cap (A). 2. Drip some oil in the cap (A) to aid in removing the cap. 3. Remove spark plug cap (A) from high tension lead (B).

  • Page 18: Checking Ignition Switch

    PB-650 IGNITION SYSTEM PB-750 3-6 Checking ignition switch 1. Disconnect lead coupler at bottom of unit and connect the probes of an ohm-meter or a continuity tester to the switch side of lead coupler and termi- nal. 2. When the ignition switch is in RUN position, the tester should indicate infinite resistance.

  • Page 19: Setting Pole Shoe Air Gaps

    PB-650 IGNITION SYSTEM PB-750 3-9 Setting pole shoe air gaps 1. Loosen ignition coil bolts and insert 0.3 mm (0.012 in) feeler gauges of two magneto wrenches 895115-00330 (A) respectively between both ends of ignition coil core and flywheel magnets.

  • Page 20: Fuel System

    PB-650 FUEL SYSTEM PB-750 4 FUEL SYSTEM PB-650 PB-750 ( A ) Air cleaner cover ( B ) Air filter ( C ) Air cleaner case ( D ) Carburetor ( E ) Intake insulator ( F ) Intake gasket...

  • Page 21: Cleaning Air Filter

    PB-650 PB-750 FUEL SYSTEM 4-1 Cleaning air filter 1. Close the choke shutter to prevent dust entering cylinder and remove the air cleaner cover and the air filter. 2. Clean the air filter and the cover with compressed air. WARNING...

  • Page 22: Adjusting Carburetor

    PB-650 FUEL SYSTEM PB-750 4-3 Adjusting carburetor GENERAL ADJUSTMENT RULES: Before starting the unit for adjustment, check the following items: - Air filter must be cleaned and properly installed. - Exhaust port of muffler must be clear of carbon. - The unit must be equipped with blowing pipes.

  • Page 23: Testing Carburetor

    PB-650 PB-750 FUEL SYSTEM 4-4 Testing carburetor 1. To fill and wet fuel pump circuit with fuel, push purge pump several times. 2. Pull off black fuel line from carburetor and con- nect pressure tester 897803-30131 (A) to fuel inlet on carburetor.

  • Page 24: Checking Fuel Tank And Vent

    PB-650 FUEL SYSTEM PB-750 4-5 Checking fuel tank and vent 1. Disconnect black fuel line from carburetor and connect pressure tester 897803-30131 to fuel line with an appropriate joint. 2. Pinch vent pipe (A) to block the air passage, and apply 0.1 kgf/cm...

  • Page 25: Checking Metering Lever

    PB-650 PB-750 FUEL SYSTEM 4-6 Replacing fuel line and grommet (continued) 4. Reinstall grommet to fuel tank together with pipe joint and pipes. NOTE: Pipe joint (D) (part number : V186-000080) has not installed on the unit serial number 35003000 and before.

  • Page 26: Checking Diaphragm And Others

    PB-650 FUEL SYSTEM PB-750 4-9 Checking diaphragm and others 1. Check metering diaphragm (A) for hardening, dis- tortion, or pin hole. Replace it as required. 2. Remove pump body assembly (B) and pump dia- phragm (C). 3. Check pump diaphragm, and replace it if hard- ened or curled at the valve tabs.

  • Page 27: Checking Pulse Passages

    4. Install gasket and insulator and the other remain- ing parts. 4-12 (Option) Assembling heavy duty air cleaner kit for PB-650 (Part number : P021-007160) 1. After removing air cleaner lid and air filter, loosen bolt 900105-05060 (A) to remove air cleaner case, carburetor and intake gasket.

  • Page 28: Handle And Control System

    PB-650 HANDLE AND CONTROL SYSTEM PB-750 5 HANDLE AND CONTROL SYSTEM ( A ) Throttle control lever ( B ) Front handle ( C ) Throttle control trigger ( D ) Ignition switch ( E ) Throttle wire ( F ) Handle bracket 5-1 Adjusting handle position 1.

  • Page 29: Replacing Throttle Wire And Switch

    PB-650 HANDLE AND CONTROL SYSTEM PB-750 5-3 Replacing throttle wire and switch 1. Disconnect lead coupler, terminal and throttle cable at the engine side. 2. Separate the right side half of handle. Remove throttle control part and ignition switch. 3. Remove tape from corrugated tube (A).

  • Page 30: Adjusting Throttle Wire

    PB-650 HANDLE AND CONTROL SYSTEM PB-750 5-7 Adjusting throttle wire 1. Loosen nut (A) and adjust the length (B) to 5 - 6 mm by turning nut (C). Fix the length (B) by tighten- ing nut (A). 5-8 (Option) Assembling static protection kit (Part number : 900500) 1.

  • Page 31: Backpack Frame

    PB-650 PB-750 BACKPACK FRAME 6 BACKPACK FRAME Backpack harness Clip Back cushion Backpack frame Cushion Hook 6-1 Replacing back cushion and harness 1. Remove backpack cushion by pulling four hooks off. 2. Replace the hooks with new ones if their elastic- ity is fatigued.

  • Page 32: Removing Backpack Frame

    1. Disconnect throttle wire and fuel pipes from Car- buretor. 2. Disconnect primary lead coupler (A) and remove ground lead terminal (B) from crankcase. For the units of PB-650 serial number up to 35003140 2K471 3. Remove three nuts and washers (C) on frame and disconect engine unit form frame.

  • Page 33: Blower System

    PB-650 BLOWER SYSTEM PB-750 7 BLOWER SYSTEM ( A ) Blower grid ( B ) Frame side fan case ( C ) Fan ( D ) Engine side fan case ( E ) Elbow blowing pipe 7-1 Replacing elbow blowing pipe 1.

  • Page 34: Replacing Fan Case Grid

    1. Remove fan case with engine block from back- pack frame (refer to 6-2 “Removing backpack frame”). Added rib For the units of PB-650 serial number up to 35003000 2. Remove former blower grid (A) from fan case. 3. Replace former engine side fan case with cur- rent engine side fan case (refer to 7-3 “Separating...

  • Page 35: Assembling Fan And Fan Case

    PB-650 BLOWER SYSTEM PB-750 7-3 Separating fan case and engine 1. Remove all the tapping bolts (A) securing fan case and replace frame side fan case if defective. 2. Remove spark plug and engine cover. 3. Insert piston stopper 897537-30130 in the spark- plug hole by hand.

  • Page 36: Assembling Engine Unit On Backpack Frame

    PB-650 BLOWER SYSTEM PB-750 7-5 Assembling engine unit on backpack frame 1. Assemble engine unit to backpack frame using three washers (B) and flange nuts (A). NOTE : Coat threads of cushions with Loctite #222 or ThreeBond 1344N or equivalent.

  • Page 37: Engine

    PB-650 PB-750 ENGINE 8 ENGINE Cylinder Cylinder cover Intake gasket Exhaust gasket Cylinder gasket Piston ring Piston Piston pin (J ) Snap ring Needle bearing Circular washer (M) Ball bearing Dowel pin Oil seal Crankcase Crankshaft assembly Woodruff key Crankcase gasket...

  • Page 38: Cleaning Cooling Air Passage

    PB-650 ENGINE PB-750 8-2 Cleaning cooling air passage 1. Remove spark plug and engine cover. 2. Inspect cylinder cooling fins for blockage with dirt or dust. WARNING Always wear eye protection when using com- pressed air. Eye damage can occur from flying particles.

  • Page 39: Testing Crankcase And Cylinder Sealings

    PB-650 PB-750 ENGINE 8-4 Testing crankcase and cylinder sealings 1. Remove muffler and carburetor. 2. Close Intake port and crankcase pulse passage using pressure plug 897826-16131 (A), pressure plate 897827-16131 (B). 3. Close exhaust port with pressure plug 897834- 79930 (C), and install muffler.

  • Page 40: Removing Flywheel

    PB-650 ENGINE PB-750 8-6 Removing flywheel 1. Remove fan case with engine block from back- pack frame (refer to 6-2 “Removing backpack frame”). 2. Remove spark plug and engine cover. 3. Insert piston stopper 897537-30130 in the spark plug hole by hand.

  • Page 41: Installing Flywheel

    NOTE : Do not use the squared end of broken pis- ton ring when cleaning the 1st piston ring groove of Cut view B PB-650 and PB-750, because the 1st piston ring is Cut view C key-stone ring and the 1st ring groove is trapezoid shape to meet the key-stone ring.

  • Page 42: Disassembling Crankcase

    PB-650 ENGINE PB-750 8-10 Disassembling crankcase 1. Remove four bolts securing the crankcase. 2. Remove woodruff key from crankshaft to avoid damage of oil seal. 3. Hold the crankcase half and tap crankshaft end using a plastic mallet to separate the crankcase halves.

  • Page 43: Assembling Main Ball Bearing

    PB-650 PB-750 ENGINE 8-12 Assembling main ball bearing 1. Heat bearing housing of crankcase to 1 10°C (230°F) for easier installation of main ball bearing. 2. Apply thin coating of Loctite #675 in circumfer- ence of the bearing housing. Do not apply the Loctite too much, or the Loctite flows inside the ball bear- ing and damage the bearing.

  • Page 44: Assembling Oil Seal

    PB-650 ENGINE PB-750 8-14 Assembling oil seal Seal lip 1. Apply lithium based grease on dust lip and seal Dust lip lip of oil seal to avoid damage of lips while inserting crankshaft into the oil seal. Oil seal section 2.

  • Page 45: Installing Piston

    PB-650 PB-750 ENGINE 8-16 Installing piston 1. Lubricate needle bearing with the two-stroke oil. 2. Insert needle bearing into the small end bore of connecting rod. 3. Place piston over the small end of connecting rod, so that the arrow mark (A) on piston points to- ward the exhaust side.

  • Page 46: Maintenance Guide

    PB-650 PB-750 MAINTENANCE GUIDE 9 MAINTENANCE GUIDE 9-1 Troubleshooting guide TROUBLE Engine does not crank. Engine does not start. Fuel leaks. Idling is not stable. Acceleration is poor. Engine stalls at high speed. Engine lacks power. Engine overheats. Engine misfires.
  • Page 47 PB-650 PB-750 MAINTENANCE GUIDE 9-1 Troubleshooting guide (Continued) Check first. CHECKING REFERENCES Fuel system / Carburetor 13 12 11 10 09 08 07 06 05 04 03 02 01 Air filter 4-1, 4-12 Fuel cap / strainer Carburetor adjustment Carburetor leakage...

  • Page 48: Service Intervals

    PB-650 PB-750 MAINTENANCE GUIDE 9-2 Service Intervals Intervals weekly 3 months Yearly Check point Service Reference Daily monthly 100 hours 600 hours Screws, bolts, and nuts Inspect / Retighten / Replace Air filter Clean 4-1, 4-12 Replace Carburetor Inspect / Rebuild...

  • Page 49: Disassembly Chart

    PB-650 PB-750 MAINTENANCE GUIDE 9-3 Disassembly chart Starter Air cleaner Spark Air filter assembly cover plug (2-1) (4-1, 4-12) (4-1, 4-12) Carburetor (4-4) Pawl Backpack Fuel Engine carrier frame tank cover (2-6) (6-2) Muffler (8-3) Engine Outer fan mount case...

  • Page 50: Index

    PB-650 INDEX PB-750 Idling (idle) speed 3, 20 Service information 2 to 7 Adapter, piston pin tool 7, 39,43 Air filter 19,25 Ignition coil 15, 16, 17 Service intervals 46 Ball bearing, crankcase 40, 41 Ignition switch 16, 27 Service limits 6...
  • Page 51 Printed in Japan 0406 TOKYO JAPAN...

This manual is also suitable for:

Pb-750

Table of Contents