Vespa smallframe engine stripdown and rebuild.
15. Replacing the engine in the frame
the engine back into the frame is basically a Haynes-Manual-style
reversal of the dismantling procedure.
might find this process easier with the scooter laid on its side. If
your petrol tank is still in place remove it and lay the bike down,
or alternatively jack the bike up, supporting it with a milk crate
or by hanging it off the ceiling. It's also a lot easier without the
exhaust silencer on the engine (although keep the manifold on there)
and without the rear wheel rim.
first thing you need to do is put the swingarm bolt through the frame
and swingarm, thereby holding the engine in at the front. Tighten the
nut properly if you don't want your engine to fall out when you
next ride the scooter. You will probably find now a convenient time
to adjust the positioning of the electrical cables, especially if you
have an ET3 with wires going into the glovebox. Fix the junction box
onto the swingarm and connect the wires to the terminals. Aren't you
glad you made notes and labelled everything correctly? If you didn't
then basically the wires from the stator connect to the same coloured
wire from the body harness. Of course fading can change the colours
but you get the idea.
you have not yet put the exhaust on the cylinder it is far easier to
do it now. With the cylinder shroud off the engine bolt the exhaust
manifold onto the cylinder using the appropriate gasket. Tourque down
the nuts and fasten the cylinder shroud back on.
next thing to do is attach all the control cables to the engine, and
let me tell you everything you have just done is child's play compared
to this. The clutch and brake cables are easy enough, but the gear
cables are awful. You need 3 or 4 hands to do it - so it's handy
that there exists something called a 4th hand tool.
you need to keep a tension on the cable, plus hold the gear shifter
on the handlebars in neutral, while holding the selector lever
at the gearbox in neutral, and simultaneously holding the little
cable clamps tight up against the selector lever - and remember
which way round the cables go! At the same time you need to use
an 8mm spanner to hold the cable clamp
tightening the screw at the top with a 7mm spanner. Not the best
of designs, nor the easiest of jobs. Add to that the fact that
gear cables are greased (or should be!) and that will make the
clamps slip, so you need to do them damn tight to prevent that.
What fun! After you have done that adjust the cable tensioners
to take up any slack or loosen too-tight cables.
Once everything is connected up and tightened and adjusted
turn on the fuel tap, pull the choke out and kick this engine to
life. (if it won't kick over check the clutch cable is not too tight,
or look at this chart for
more clues. Now go for a ride to check everything works, adjusting
cables etc as
off at the
home to buy yourself a well earned four-pack of beer.