Engine Disassembly - Large Frame

• now that you have drained the oil and removed the motor from the scooter its time to tear it down.
• A engine stand and bench vice will make you life alot easier
• I will spin it around to show you how cool this engine stand is and how much access it gives you

• Lets begin
• Start by removing the forked spark plug clip

unclip the high tension coil wire

remove the bottom screw from the flywheel cover and cylinder shroud

remove the bolt from the cylinder shroud

remove it

pull the spark plug and throw it away

remove the spacer nut

remove the 4 nuts that hold the head in place

• you should have a
• nut
• flat washer
• lock washer

now you can remove the head

next the cylinder

check the piston for scoring, cracks, etc..

remove the cir clips that hold the wrist pin in place

they may look like this or you may need special cir clip pliers to remove them

use the special wrist pin punch

to push the wrist pin out

remove the small needle bearing

remove the base gasket (replace it)

remove the rest of the screws that hold the flywheel cover on

remove the flywheel cover

• remove the rubber plug
• you can pry it out with a screwdriver

this is an access hole got points adjustment

use a flywheel holder to be able to loosen the flywheel nut

• this method works if you do not have an impact
• strike the end of the ratchet with a hammer it works quite well

behind the nut there is a star washer

• use the flywheel puller
• some Vespa scooters have a cir clip that acts as the puller
• back the bolt all the way out

insert the puller and tighten it all the way

hold the puller and tighten the bolt

the flywheel will come right off

• inspect the woodruff key for damage
• also be careful it doesn't fall out (its pretty small)

if the flywheel was ever too loose this will be damaged and will need to be replaced

disconnect the coil wire

• remove the junction box
• it can be pried up with a screwdriver

• it is a good idea to mark the position of the stator before you remove it.
• 3 screws hold it in place remove all of them

you should have a flat and wavy washer

pull the stator off

• feed the wires down through the case
• inspect them for brittle wires or if the copper is green replace them

we are getting there

remove the carb box top screws

there are 2 of them

This is what they look like

remove the carb box top

remove the rubber gasket from the top of the box

unscrew the air filter screws

• they are different
• S 14743 this is the back one
• S 14436 this is the front one

remove the air cleaner

• remove the carb bolts
• 11mm socket
• there are 2 of them and they have a flat washer and lock washer

see

• remove the carburetor
• I usually leave the bolts and washers in the carb body its less stuff to lose

remove the gasket with a pick tool or just rip it because you will replace it

• remove the screw that is under the gasket
• this holds the carb box on

the carb box will now lift off

remove the gasket under the box and replace it

spin the motor to get access to the rear wheel

• remove the cap
• you can pry it off with a screwdriver

• pull the cotter pin out with pliers
• bend the ears straight

pull it out

use a 22mm socket to remove the castle nut

there is a washer behind the nut

now you can remove the hun it should just slide right off

• remove the clips on the brake shoe post
• a pair of needle nose pliers work well

• after you remove both of the clips
• push the brake lever as if you were stepping on the pedal

this will allow you to stick a pry par or screwdriver under the brake shoe between the pin and the shoe

• now get another pry bar and ply like so
• the brake shoe will come right off

this is what you should have

remove the 3 screws that hold the back plate

Remove the back plate

• There are 4 rubber O-Rings behind it
• Remove them with a small pick tool

This is what you should have

Next pry out the Rear Hub Seal

Remove the 3 screws that hold the Clutch Cover they are 6mm and you use a 10mm socket

You should have 1 6mm Lock and 1 6mm Flat washer

Remove the cover

remove and replace the O-ring off the cover

• with a small pick tool remove the pressure plate
• pull down on the retaining clip

then pull out like this

You will notice the tab washer has one of the tabs bent into the castle nut bend it out so you can remove the nut.

replace one of the clutch cover bolts

insert the clutch holding tool (like so you will do it opposite to install the nut)

Use the clutch nut removal tool to remove the nut

it takes a 17mm socket or wrench

• after you remove the nut use 2 prybars or 2 large screwdrivers to help pry the clutch off
• it should not take too much force (don't damage the case)

you can remove it the rest of the way by hand

pull out the washer and replace it

• remove the spacer from behind the clutch
• and remove the woodruff key

this is what you should have

• spin the motor around to the front side
• remove the coil bracket using a philips srewdriver and an 8mm wrench
• there are 2 of them

• remove the coil
• you shouldn't replace it if it is working but its not a bad idea to carry an extra one (generally they work or they don't)

• now move on to the selector box
• remove the 2 7mm nuts with a 11mm socket

you should have 2 nuts, 2 flat washers, and 2 split washers

• once you have the nuts removed put a screwdriver in the pinch bolt area
• spin it down as if you were changing gears

• it will come off like so
• you can pull it off the rest of the way by hand

remove and replace the gasket (it comes in your gasket set)

• now you can begin removing the case bolts
• there are 8 bolts one of them is longer than the others (its the one that the cable holder is attached to)
• you will probably not be able to get the longer one out. you can just remove the nut and washers and leave it in the case half
• behind where the stator was there are 4 studs the you will have to remove the nuts from as well

the bottom bolt is backwards and the nut is on the other side

• after you remove all 12 nuts and washers you can split the case halfs
• this tab can be used to force them apartif you dont have the Case Seperator Tool

use a punch and tap the bottom apart (gently)

• once it seperated a little use the rubber mallet and tap the top
• repeat the procedure on the bottom then top, working the halfs apart a little at a time.
• the kick start gear and spring will probable fall out, just make sure you find them.

if you have the Case Seperator Tool it will be ALOT easier and there is less chance you will screw up the case

start by backing out the large bolt on the puller all the way

using the thumb screws provided thread them into the holes that hold teh flywheel cover in place

• there are 3 of them
• thighen all of them as tight as you can get them by hand

now slowly tighten the bolt

• the case will begin to seperate
• after a few more turns you will be able to seperate it by hand

if the kick start gear spring didn't fall out remove it

remove the case gasket and don't even think of reusing it

a good way to remove the rear axle is to thread the castle nut on backwards

tap it with a hammer

once you knock it free you can remove it by hand

spin the motor and bend the Tab Washer so you can take the nut off

remove the nut

you cna buy a Kit to replace everything (since you are bending the tab washer its a good idea to replace it)

• to remove the Cush Drive just push the end you just took the nut off.
• with your other hand hold a rag to catch the Needle Bearings

dont lose these guys

simply pull the shaft out

• and pull the Cush Drive out
• HERE are some instructions on how to Rebuild it

• I usally don't remove the Oil Sling unless Im gonna sand blast the case but if you do DON'T FORGET TO PUT IT BACK IT.
• When you have to motor put back together and you see it in you parts bowl or whatever you use to store your parts you will be pissed

to remove the crank you can do the same method as removing the rear axle by putting the clutch nut on backwards

another way is to use a pointed puch

set it into the recess in the crank and tap a tap a tap a

you can finish it off with the rubber mallet

pop the Clutch Side Seal out with a screwdriver and REPLACE IT

remove the large CirClip that holds the Main Bearing

to remove the beaing you will need the Bearing Tool

insert the shaft into the canter of the Bearing from the Clutch side

insert the pin in to other side of the tool

put the cup piece on and thred the nut on

just make it snug

insert the bolt in the shaft to tighten it on the bearing

now tighten the large nut while holding the shat from turning

• the bearing will come right out
• You can also tap it out with a large socket (but be careful)

• now remove the Rear Hub Bearing
• start by removing the circlip

from the inside punch it out you can use a long socket extension or a long punch

it will come right out

• next remove the Brake Arm and Cam
• the only reason to remove this is to replace the 2 rubber o-rings on the Cam

let the tension off the arm by removing the spring from it

pull out the cotter pin

Slide out the Cam

here are the O-Rings (they are in the Gasket Set)

now remove the Kick Start Quadrent

• just tap it with the rubber mallet
• catch them on the other side

• the Quadrent and Spring will come out at the same time
• there is an O-ring inside the case you should replace (it can be a cause of an oil leak)

remove and throw away the KickStart Buffers

same goes for the FlyWheel Side Seal

use the Bearing Extractor to remove the FlyWheel Side Bearing

use the same procedure as above

remove the Output Shaft Bearing

• the best way I came up with was to tap it out with a small aluminum punch
• you will have to replace if if you do it this way

if you are reusing the Crankshaft you will have to remove the half of the FlySide Bearing that stay on the Crank

• you can cut it off (not reccomended)
• or use this Puller

this lip goes under the Bearing

like so

insert the Crank Wedge (or a wooden wedge)

insert the puller with the collar all the way up

gently tap it down until it bottoms out

hold the tool with a wrench and twist clockwise by hand