Ce tutorial aims at you help change the gearbox bearings of a type engine Generic on your box 50cc thanks to pics and explanations associated. This tutorial is quite complicated, you have to be patient and rigorous! It is in two parts: Disassembly then assembly.
We advise you to do the tutorial at the same time HOW TO CHANGE YOUR CRANKSHAFT ON ENGINE GENERIC. Discover all of the box bearings suitable for your 50cc with gearbox with Type K engineSR GENERIC, HANWAY .....
Difficulty :
Temps necessary:
1 hours 30 minutes
1) Start par take your motor out of the frame and drain it. For this, consult this tutorial.
2) Remove the ignition cover (4 screws).
3) Remove the candle.
4) Place the piston block in place of the spark plug.
5) Remove the nut from the ignition rotor.
6) Put on the flywheel puller to remove the ignition rotor.
7) Remove the two screws with the Phillips screwdriver.
8) Unscrew the 2 screws from the support using the socket wrench.
9) Disconnect the ignition - Be careful to collect the screw and the washer.
11) Remove the ignition stator.
11) Unscrew the 2 starter screws.
11) Remove the starter support screw on the outside of the engine.
11) Remove the starter using the mallet.
11) Remove the clutch housing (8 screws).
11) Then use the mallet to take out the clutch housing.
11) Remove the 4 screws, washers and springs from the pressure plate.
11) Remove all clutch disks.
11) Then remove the central axis.
11) Unfold the bell nut retaining washer using a screwdriver and hammer.
11) Then remove the clutch nut. Help yourself with the clutch key.
11) Remove the clutch nut (watch out for the washer below)
11) Remove the clutch housing.
11) Remove the clutch washer using flat screwdrivers.
11) Remove the kick pin. Be careful to recover the pinion in the hole of the axis
11) Disassemble the balancing shaft pinion and the crankshaft pinion (watch out for washers and keys)
11) Remove the clutch gasket.
11) Collect the ball and the clutch rod.
11) Unscrew the intake pipe (4 screw).
11) Collect the valves.
11) Remove the piston block
11) Remove the 4 screws and the 4 washers located on the cylinder head, then the cylinder head.
11) Remove the cylinder.
11) Remove the piston pin clip.
11) Remove the piston pin and the piston, pushing with the screwdriver
11) Remove the needle cage.
11) Remove the base gasket.
11) Unscrew and remove the clutch rod.
11) Remove the circlip from the kick pin.
11) Remove the screws from the crankcase (12 screws).
11) Turn the engine over.
11) Remove the screw from the crankcase behind the balancing pinion.
11) Put the nut on the crankshaft, then tap it with the mallet until the engine opens.
11) Remove the crankshaft nut. Open the engine.
11) Remove the gear selector shaft, collect the washer.
11) Remove all of the gearbox elements, starting with par the barrel.
11) Then the forks.
11) Remove the first tree and then the pendulum.
11) Remove the second tree.
11) Put the nut on the crankshaft, then tap it with the mallet.
11) Remove the nut
11) Remove the crankshaft.
11) Get the bearing.
11) Remove the 2 screws from the crankshaft bearing. Then turn the housing over.
11) Remove the oil seals and bearings from the crankshaft and the gearbox using a pin and mallet. The number of bearings varies by model.
11) Do the same on the other part of the housing.
1) Fit the new crankshaft bearings. Press them down well with the mallet. Tip: Put a key when you tap on it to prevent the crankshaft from distorting.
2) Install new bearings and oil seals. Help yourself with a fairly thick shaft and a hammer to drive them.
3) Proceed in the same way on the other part of the housing.
4) Reposition and tighten the 2 bearing screws
5) Replace the engine balancing arm.
6) Replace the gear shafts.
7) Position the first fork.
8) Using the needle-nose pliers, position the locking finger.
9) Replace the barrel.
11) Replace the axis of the first fork. Tip: Grab the fork with pliers and hold it to put the axle.
11) Replace the second fork.
11) Replace the transmission axle.
11) Reposition the washer on the barrel.
11) Do not forget to put the washers back on the selector shaft (1 washer at each end)
11) Replace the gear selector shaft.
11) Heat the casing with a torch.
11) When the crankcase is hot, place the new crankshaft.
11) Apply joint compound all around the housing.
11) Heat with the torch the other part of the casing.
11) Close the cover by tapping on it using the mallet.
11) Replace the housing screws (12 screws). Tighten vigorously.
11) Wipe off excess sealant properly.
11) Replace the nut on the crankshaft.
11) Using the mallet, tap the crankshaft nut to center it.
11) Rotate the crankshaft to make sure it goes back properly. Remove the nut.
11) Install the crankshaft oil seal. Push in well with a pin and mallet.
11) Put on the crankshaft ring seal.
11) Place the crankshaft ring.
11) Replace the key.
11) Replace the 2 crankshaft gears, the washer and the nut.
11) Replace the balancing shaft key.
11) Place the pinion paying attention to the timing of the pinions.
11) Replace the nut on the balance shaft pinion.
11) Lock the balancing shaft gear.
11) Tighten the 2 sprockets using the ratchet.
11) Unlock the pinion.
11) Replace the clutch housing washer.
11) Pour a little can oil.
11) Replace the clutch housing.
11) Replace the washer
11) Then the clutch nut.
11) Replace the clutch housing nut retainer.
11) Replace the nut.
11) Tighten the nut using the clutch key.
11) Bend the clutch retainer nut retainer washer.
11) Replace the clutch rod and ball.
11) Replace the clutch rod.
11) Install the clutch discs, putting transmission oil between each disc. Alternate filled disc and smooth disc.
11) Replace the pressure plate - pay attention to the mounting mark.
11) Position the 4 springs, washers and screws.
11) Tighten vigorously.
11) Install a new crankcase gasket.
11) Replace the clutch cover. Tapouse the mallet to close it securely.
11) Replace the 8 clutch housing screws. Tighten properly
11) Replace the clutch rod and tighten. Remember to reposition the spring in the notch.
11) Position the rod screw and tighten.
11) Fit the crankshaft oil seal. Push in well with the mallet.
11) Position the key on the crankshaft. Press it down with a pliers.
11) Position the stator.
11) Tighten the 2 screws of the stator support.
11) Then the 2 plug connection screws.
11) Finish par the ignition cable.
11) Replace the rotor and tighten the nut.
11) Replace the starter and fix - 2 screws.
11) Place the starter mounting bracket
11) Replace the screw using the BTR key.
11) Tighten the clamp on the mounting bracket.
11) Refit the ignition cover - 5 screws.
11) Replace the valves. Position the intake seals.
11) Replace the intake pipe. Tighten the 4 screws.
11) Unscrew the kick stop.
11) Position the kick.
11) Check the tension by turning the kick.
11) Reposition the kick stopper, tighten slightly.
11) Remove the kick.
11) Tighten the kick stopper.
11) Put the new base gasket.
11) Lubricate the new needle cage, then position it.
11) Put the plunger. Press in the axle with the screwdriver.
11) Replace the piston pin clip.
11) Reposition the cylinder. Remember to lubricate the base.
11) Position the cylinder head.
11) Replace the 4 washers and the 4 nuts.
11) Tighten the nuts with the torque wrench - 18 NM.
You can now reset your engine by helping you this tutorial.