engine series ID advice needed

[johnnyXS]

I have 3x engines and I am not sure if they are all series 1 or not ?
I have checked several sites including the archive and my head is hurting

Could someone please confirm which series for these 3x engines
150Li* 7741##
150Li* 7967##
150Li* 7381##

[carlos fandango]

Yep all Series 1

all from April 59

[johnnyXS]

thanks Carlos !
I was rather surprised to discover that today .
An ebay importer sold me a series ll engine and a seperate series 3 crankcase

I didn't bother to check as I spoke to the owner several times on the phone , besides they are well known and I thought reputable.

Just shows you can't trust anybody these days

[Digger]

A) Do you mean crankcase cover?

B) What's the problem it will fit?

[johnnyXS]

no digger a cover doesn't have any ID number on it .
The problem is that the seller advertised the engine as a series ll but it appears that it was actually just a series 1 with the later type silent bushes fitted

later I found out that the crankcase had damage to the underside so he sent a spare crankcase as a replacement telling me that it was a series 3 Special. It looks like that crankcase was also a series 1

I see last night that he is still advertising series 1 engines as series 3 specials .

Hence the ID question because there is some confusing identification information out there so I wanted to check

[johnnyXS]

well last night I found another list of frame and engine numbers on the Lambretta Archive site which seems to throw the whole question up in the air again

The ebay importer I bought the engine from is still listing 150 Li* Special' engines with a 727### number ???????????????

How can a supposedly series 1 engine from 1958/59 be fitted to a 1964 onwards series 3 Special ?

Lambretta Archive have a note which states quote' Li 150 engine numbers go up into the 700,001 range and confusion can arise as the Li 150 Special engines also feature within that number range

How can you tell whether a bare crankcase is a series 1 or a series 3 Special if you have no cover or gears and other components to compare ?my head hurts

[HxPaul]

Early s1 crankcases have 6mm studs for the exhaust to mount on,later models have 8mm studs.Early s1 crankcases also have no recess for the dished oil thrower washer.

[johnnyXS]

thank you paul thats a good point but I'm not clear how that helps me ?

When you say 'early' and 'later' what engine numbers are you referring to ?

My dilemma is I have 3x engine numbers starting with 7 which are proportedly Li 150 special engines .
Engine numbers which begin with a 7 like the three that I have listed are apparently 1958/9 series 1 engines according to Carlos and several Lambretta identification lists .

My query is were the early 1963 1964 Li150 specials fitted with series 1 engines starting with 7 ? in which case could the three engines I have listed be Li150 special engines and if so how can you tell them apart from standard Li150 engines without stripping them and counting the gear teeth etc

[HxPaul]

"engine numbers which begin with a 7 like the three that I have listed are apparently 1958/9 series 1 engines according to Carlos and several Lambretta identification lists"

The series 1 Li 150 was started in April 1958 and ended in October 1959 so I would say all engines built in 1958 would be classed as early and all engines built from and including January 1959 would be classed as late,you will have to find out what number they started at ie.700001 and cross reference the numbers on your engines to see if there early or late engines.By the way,as far as I know,series 1 Li150 engines start at 5*****and end at 6*****.

[johnnyXS]

"

The series 1 Li 150 was started in April 1958 and ended in October 1959 so I would say all engines built in 1958 would be classed as early and all engines built from and including January 1959 would be classed as late,

as far as I know,series 1 Li150 engines start at 5*****and end at 6*****.

This doesn't help me identify my engine numbers paul
You've just thrown the same question back to me . ?

The Lambretta Archive state that some Li150 special engine numbers go up into the 7*****
I presume that all Li150Special engines would be Series 3 yes ?
Why is it that the three so called Special engines that I have have 7***** numbers yet Carlos you and several website listings say that these engines are series 1 engines . ?

Its beginning to look to me like Innocenti used some 7***** numbers for their Li150 series 3 Special engines as well as series 1 engines .

I really need someone that owns or has owned a Li150 special with a verified original engine with a 7***** number that can post a picture so that I can compare their engine with those I have for identification purposes .
Guessing is not really helping me, its just confusing the issue further really.

[HxPaul]

Series 3 Li 150 engines and series 3 Li 150 Special engines both have 7***** as there numbers,as for series 1 engines,I'm sorry I cant help you any more than I have.

[steve t]

Have a look at scooterdepoca.com may be of some use as mentioned above series 1 motors have 2x m6 studs to support exhaust mount instead of m8 like series 2&3

[johnnyXS]

Have a look at scooterdepoca.com may be of some use as mentioned above series 1 motors have 2x m6 studs to support exhaust mount instead of m8 like series 2&3

so basically if the crankcase has all 6mm studs its a series 1 and cannot be a Li150 special yes ?

The engine that came in my 64 Special has definitely got 6mm exhaust studs as has the Special crankcase that this seller told me was a Special
I'll contact them and ask them what source they are using to identify their engines .

What I could really do with is a picture of an authenticated Special engine fitted to a Li150 special which I can then compare with mine
thanks for your post

[HxPaul]

If the "Special" crankcase that you have has 6mm exhaust studs,then it is a series 1,as later cases changed the exhaust mount studs to 8mm ............as I said in an earlier post.

[carlos fandango]

.

[Adam_Winstone]

Yep, the exhaust stud size (the 2 that take the main bracket form the top of the exhaust body) will tell you whether you are dealing with a SI casing (6mm, same as all of the other side casing studs), whereas the late 150 Special casings that use confusing/clashing numbers will have 8mm stud threads for these 2 exhaust studs. You can also tell as the SI casings would have no machined chamfer for an oil thrower washer under the front sprocket assembly, whereas the 150 Special casings would.

The late 150 Special casings would also have:

1. Large engine mounts, rather than the smaller SI type.
2. The additional fixing point on the underside of the casing that serves to triangulate the exhaust mounting. No SI casings have this additional lug and thread as they didn't appear until later SIII casings. The 'odd' 150 Specials that confuse the number sequence are very late, e.g. my example is a genuine G reg!

I hope that some of the above helps.

Adam

[johnnyXS]

thank you Adam thats sort of helps but unfortunately the 2x Special cases that I have would appear to be both early ie before silver and gold models.
The engine that came fitted to my 64 Special has the engine number 150Li* 7381## It has 8mm studs and the silent blocks fitted which were finished nuvo white so presumably that is actually an authentic early Special engine ?

The empty 'Special' case I was sold also has the early style silent blocks which also show traces of white paint this number is 150 Li* 7967## and 8mm studsI have no idea what age this is but I will check for the oil thrower depression tomorrow.
.
Johnny

edited fot errors

[Adam_Winstone]

I would suggest that any with 6mm studs are not Special engines, likewise any fitted with the smaller engine mounts are not Special engines. Also when referring to the later Special casings, I don't mean Silver or Gold examples, rather, I am referring to the much later examples that appeared as an odd batch much later, as per my original 1969 G reg example (one owner from new, prior to me).

If any of these motors have barrels on them still, there are various markings, fin differences, inlet port shapes differences (at gasket face), porting differences, etc. Also SI cranks will have brass bush small end bearing, whereas Special motors will have needle roller.

Adam

[Adam_Winstone]

PS - My other thought is that reviewing some of the 150 Special press release / test ride reports will show exactly which features were incorporated into early Specials so should point to differences that should be on all Specials, rather than earlier SI features.

[johnnyXS]

Thank you Adam for your help .
I need to accumulate a lot more brochures, press releases and test reports etc . Online information cannot really be relied upon as most if it appears to have been plagerized from the same unproven sources.

I got the chance to inspect the 3x crankcases today and I think the mystery is resolved.

The engine in my imported 64 LiS150 special has both 8mm exhaust studs (actually bolts have been retrofitted at some point !) and it has the smaller white silent blocks( Third image) number 150Li 7381##

The unknown spare engine has 8mm exhaust studs and no silent blocks so this is not a series 1 (second and First images )