139QMB Bearings, Seals, Bushings, And Torque
Nov 11, 2015 11:55:20 GMT -5
Fox, Dogbite, and 1 more like this
Post by 90GTVert on Nov 11, 2015 11:55:20 GMT -5
This thread is full of all sorts of specifications for Chinese 139QMB / 1P39QMB engines. There are some strange variations in Chinese scooters, so it's always best to check your scooter before working on it or ordering parts for it and consult a service manual. Use the info here at your own risk.
Bearings
Crankshaft, CVT Side
| Number | I.D. | O.D. | Thickness |
| 6204 C3 | 20mm | 47mm | 14mm |
Crankshaft, Stator Side
| Number | I.D. | O.D. | Thickness |
| See Below. | 17mm | 42mm | 13mm |
These bearings are not a common size. They may be marked in different ways, including 6302-SP, CS-SC03A39, or other designations. A typical 6302 bearings does NOT work because it has a smaller inside diameter. Honda part # 91002-HP1-671 should work or you can search for 17x42x13 bearings and find them from other manufactures or find the special bearings for this engine.
Gearbox
Seals
Crankshaft, CVT Side
| I.D. | O.D. | Thickness |
| 19.8mm | 30mm | 5mm |
Crankshaft, Stator Side
| I.D. | O.D. | Thickness |
| 16.4mm | 30mm | 5mm |
Primary Drive Shaft
| I.D. | O.D. | Thickness |
| 17mm | 30mm | 6mm |
Rear Axle
| I.D. | O.D. | Thickness |
| 27mm | 42mm | 7mm |
Bushings
Engine Mount (x2)
| I.D. | O.D. | Thickness |
| 10mm | 28mm | 22mm |
Rear Shock Mount
| I.D. | O.D. | Thickness |
| 8mm | 20mm | 19mm |
Other Info
NGK Spark Plug Numbers : CR7HS, CR7HIX (iridium)
Spark Plug Gap : 0.024"-0.028" / 0.6mm-0.7mm
Valve Clearance/Lash : 0.002"-0.005" (Commonly Used : 0.002" Intake / 0.003" Exhaust)
Engine Oil Drain Bolt : M12x1.50
Gear Oil Drain Bolt : M8x1.25
Magnetic Drain Plug Kit At Amazon
Flywheel Puller : M24x1.0 RH
Flywheel Puller On Amazon
Torque Specs
Description | Torque |
Axle Nut (Rear Wheel) | 70-80ft-lb |
Clutch Bell Nut | 35-40ft-lb |
Clutch/Torque Driver Nut | 35-40ft-lb |
Cylinder Head Nut (x4) | 10-15ft-lb |
Side Cylinder Bolts (x2) | 6-8ft-lb |
Flywheel Nut | 30-35ft-lb |
Variator Nut | 28-35ft-lb |
Thread Size | Torque |
M6 | 6-9ft-lb |
M8 | 10-20ft-lb |