LAMBRETTA ENGINE LUGS SNAP ITS A FACT!
Now that may sound very scary to some people!
For what ever reason the Lambretta engine lug can snap and its very common.
Now its usually a major pot hole or a good old fashioned smack with a hammer, usually trying to remove or fit an engine mount!
The usual weak side, is the left hand side. Call SIL what you want, but they did do something about it and they added extra strengthening ribs to try and help solve the problem. And it worked – sort of – Indian casings snap less than an Italian or Spanish casing! But even they snap!
It’s very rare the right hand side snaps, this is a more solid design over the left side. Id say maybe the ribs on the left need making thicker. The percentage is about 90% left to 10% right!
When I look and compare Lambrettas casings to Vespa, I’ve always said the Vespa casing is too thin compared to the Lambretta casing. Has it anything to do with saving money on castings I wonder? Or is it something to do with quality of castings? I’ve found Vespa casings harder to weld than Lambretta casings but this always vary! You can have a perfect Innocenti casing and then a very bad one. It’s the same with SIL and Spanish casings.
Compare to an English or German designed casting they are usually over kill, but still crack and snap!
A lot of it is about getting the thicknesses right at the right point. Have some problems and re adjust to improve the casting and moulding – but this is very expensive which leaves us with casings which have had the same design for over 60 years!
Engine lugs snap off! Why, how, when?
When they go some try to re weld and just add loads of weld to make the repair stronger. But if this isn’t done right you end up with a repair like the one shown. Far too much welding rods over welded on a crack, BUT underneath its not welded correctly!
I was asked to ……. just clean up the weld!
I don’t do this any more – this example is why!
Even when you do what you think is a perfect weld, you need to look at holes after its all ground back. These holes need re addressing, drilling out and rewelding – other wise the repair is not as good as it should be.
Check this one out…..
