LD Engine Removals & Rebuilds
How I remove my engines and steps I take.
Note, this is for a later model. Earlier models with vary slightly, but the principles are the same.
Remove fuel tank to allow lifting and manoeuvring of the engine, once the items below are removed (Old / early models also require the cylinder head to be removed as well, to get the fuel tank out)
Remove Engine Cowl / Cover (Image 1 – Item 31 and 34)
Remove Flywheel / Magneto (Image 2 – Item 14). so that the Flange below can be removed.
Optional – If leaving off for some time, you may want to remove the stator plate and coils and place inside the Magneto to aid in not losing too much magnetism, depending on how long your stripping it for (Several months or maybe several years!).
Remove the Flange cover (Image 1 – Item 33) There is a screw that tightens this onto the Flange itself. This screw can be difficult turn at times. If it is too difficult, you may want to try and tap the cover off gently with a rubber or wooden mallet and deal with the screw later. This needs to be removed as the engine bolt will hit and damage it, when taping this out later.
Torsion Bar – Upper section: (Image 3 – Item 27 – front bar) – Remove cir-clip (item 20 cir-clip x2) (Item 25 – lock washer x1) (Item 26 – washer x2) – Note again, this is the front bar section. Tap / knock item 27 (bar) out. Once it is out, move the bar (Item 21) up, so that it is no longer connected to the engine case. Note: It must be moved up and out the way, as when you tap the torsion bar below out, Item 19 and 21 move. So if item 19 is still near the engine case, you risk damaging the engine case.
Notes: On old Lambrettas, there is a roller pin / bearing. These are easy to damage and or lose the small roller pins (See item 22 in the image. These little roller pins sit inside a cage). Copper replacement parts are available to replace these. When reinstalling, take extra care in reinserting the bar as you can break the engine case if you apply too much force and get the alignment slightly off.
Torsion Bar – Lower section: (Image 3 – Item 28) Remove dust cover (x2 – Item 32) / Remove cir-clips (x2 – Item 20) / Remove thick washers (x2 – Item 31 – they may look like part of the frame, but they are there!) and tap the torsion bar out, hitting it from the carburettor side. If the bar has not been removed in many years, it may require much force to hit it out. I use an old long wrench extension to hit mine out. You will notice that the entire (Item 19) moves as well. Hitting from the carb side, 28 and item 19 move as one unit and remember to ensure item 21 has not fallen down and is sitting back inside the engine mount area.
Additional Information 1: The number of splines on each end of the bar (item 28) are different. This enables the position of the torsion bar arm to be finely adjusted, which in turn alters the ride height
Additional Information 2: You could also hit the bar from the other side. I have always done mine by hitting from the carb side, which in turn move moves item 19 as well. Hitting it from the other side, can be a pain to get it out the other side, due to additional information 1 comments.
Item 34 – Remove the engine bolt.
Unfortunately, engine bolts can also be a pain to remove at times. I start off by using the long wrench extension and then use an old long screwdriver towards the end. Reminder – If you did not remove your flange cover, this is when you may break part of it off.
Your then ready to remove the engine.
CLICK ON IMAGE TO INCREASE THE SIZE
Summary information For Engine Removals & Rebuilds
Removals
Mag Flange – Try to avoid taking the Mag Flange off if you can. Some come off with hard effort. Some are even harder and you may break the mag flange to try to get it off. I have one at the moment that I am going to put in the oven for a while to heat it up before trying to prize it off, having spent around 7+ hours (+ 1 year soaking in diesel) trying to get it off without breaking it.
x2 Engine Bushes – If replacing the engine bushes, they are difficult to get out. Treat with caution when replacing as you can break the bottom engine casing if too much force is used.
Main Big Engine Pin / Bolt – The engine mount pin (by the stand) tends can be difficult to remove at times. When removing this, be careful of the mag flange side cowl, as the engine pin will knock a bit of this off if it is not removed. To remove the flange cowl part, the magneto / flywheel should be removed.
Stand – The stand pin also seizes up most of the time and requires a hammer and force to get out. I use rust penetrating fluid and a long wrench extension pole (For this and the engine pin) as the tool, to knock it through.
Putting back together
Nuts & Bolts – You would normally put the same screw, nut and bolt back to into where you removed them from. This is not always possible though and if you received a Lambretta in bits.
Oil Leaks – For oil, expect some leaks to happen if you over fill. Especially by the kick start mechanism area.
Cylinder Head – For the cylinder head area, it is very easy to over tighten the head / nuts. Avoid using a torque wrench anywhere. If your intending to take the head and cylinder of, check for hair lines cracks.
Torsion Bar Note 1 (Original roller bushes), it is easy to push the bars back through and damage the roller bearing. Replacements are bronze bushes easily found at various shops.
Torsion Bar Note 2 – When pushing the torsion bars back through, be careful not to hit very hard. If your off by a few mil and tap too hard you will break the engine casing.
Transmission / Gears – If taking the gears apart, be careful not to lose the three (or two, depending on if someone has rebuilt it and replaced the two at one end with one think washer!) slightly thick metal spacer washers (x2 on one end and x1 on the other end). (Images from manual to follow on spacer locations)
Transmission shaft – If you remove this, many roller pins may fall off. The easiest way to put these back on is with a little grease, to hold them all in place.
Kick Start – The kick start lever area also has spacer washers that when you remove the kick start, they sometimes fall away and leaves you wondering where they came from (Images from manual to follow on spacer locations)
if you have put everything back together and have problems kick starting and fireing it up, you may want to look at No Spark Tips & Tricks post
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