Series MM Questions

for those with Series MM sidevalve cars produced between September 1948 and February 1953
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palacebear
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Re: Series MM Questions

Post by palacebear »

Hi.
Answer is NO :)

Series MM with side-valve engine was replaced by split-screen Series 2 with OHV engine during 1952. Series 2 was facelifted during 1954 but retained split-screen until phased out during 1956.

If your shell still has a chassis/id plate on the bulkhead, the chassis number should tell you whether it's a Series MM shell (prefix SMM) or a Series 2 (prefix starting with F).

If it IS a Series MM shell there may, depending on it's age be a number of differences between it and earlier/later shells.
1956 4-door called Max
JohnV
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Re: Series MM Questions - Series MM vs II, "SMM" vs "F" prefixes

Post by JohnV »

With respect, I don't think this is quite correct.

The new ID plates with F-series prefixes were introduced 1 April 1952, presumably to rationalise with the Austin system in the newly combined BMC. It started with serial # 139439, and the old Nuffield practice of allocating separate RHD and LHD sequences ended.

But the first Series II car wasn't until August 1952, at chassis # 160001. So I believe all Series II Minors should have "F" prefixes, and even some late Series MM cars as well.

best, jv.

palacebear wrote: Sun May 20, 2018 11:31 am If your shell still has a chassis/id plate on the bulkhead, the chassis number should tell you whether it's a Series MM shell (prefix SMM) or a Series 2 (prefix starting with F).

If it IS a Series MM shell there may, depending on it's age be a number of differences between it and earlier/later shells.
I have two Minors in upstate New York. One is the 1961 Traveller my dad bought new that year in London, where I was born. It's had a hard life but is still running cheerfully at 54K miles. The second is the oldest Minor confirmed to survive in North America, a LHD high-light Tourer built in April 1949. It's a total basket case, but will be restored over the coming years.
palacebear
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Re: Series MM Questions - Series MM vs II, "SMM" vs "F" prefixes

Post by palacebear »

JohnV wrote: Fri Aug 31, 2018 1:52 pm With respect, I don't think this is quite correct.

The new ID plates with F-series prefixes were introduced 1 April 1952, presumably to rationalise with the Austin system in the newly combined BMC. It started with serial # 139439, and the old Nuffield practice of allocating separate RHD and LHD sequences ended.

But the first Series II car wasn't until August 1952, at chassis # 160001. So I believe all Series II Minors should have "F" prefixes, and even some late Series MM cars as well.

best, jv.
I think you're probably correct. I'd overlooked the 'small' fact that S-MM and S-II were built alongside each other for a few months, hence S-MM with numbers higher than 160001 would in all probability have F prefix numbers! :oops:

I've already got my new copy of Minor Matters and was fascinated by the feature on Clementine. What a great project! I wish you well with her and hope that you keep us all updated on your progress :)
1956 4-door called Max
JohnV
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Re: Series MM Questions - Series MM vs II, "SMM" vs "F" prefixes

Post by JohnV »

Thank you for the good words! :) Clementine will be quite a project, for sure.

But, hey, everyone needs to do one ridiculously complicated, horrifyingly expensive rotisserie restoration in their life ... right?
palacebear wrote: Fri Aug 31, 2018 4:39 pm I've already got my new copy of Minor Matters and was fascinated by the feature on Clementine. What a great project! I wish you well with her and hope that you keep us all updated on your progress :)
I have two Minors in upstate New York. One is the 1961 Traveller my dad bought new that year in London, where I was born. It's had a hard life but is still running cheerfully at 54K miles. The second is the oldest Minor confirmed to survive in North America, a LHD high-light Tourer built in April 1949. It's a total basket case, but will be restored over the coming years.
firedrake1942
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Re: Series MM Questions

Post by firedrake1942 »

No dividdd into mm, early s2 and late s2
Mick Lynch
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Re: Series MM Questions

Post by Mick Lynch »

What’s people’s thoughts on these NOS rings? Salvageable?
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philthehill
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Re: Series MM Questions

Post by philthehill »

Only good for the scrap bin unfortunately :cry:

sirrom918
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Re: Series MM Questions

Post by sirrom918 »

I totally agree with Phil's comment. ESM can supply new piston ring sets from standard size through to +60 for the 918cc Side-Valve Series MM Minor.

https://www.morrisminorspares.com/engin ... 40-p830018
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Mr Spigot
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Re: Series MM Questions

Post by Mr Spigot »

I hope this is posted in the right section; while I have had A-Series Morris Minors for nearly 40 years, I have just entered the world of MMs having also acquired a 1952 convertible with original 918cc engine and am on a steep learning curve!
Are there any recommendations for spark plugs other than Champions? I know the current application is L86 (replacing L10) but wondered if there is much to chose between different makes now. I have used NGKs in my other car with a 1275 Midget engine, after having troubles with Champions many years ago and was advised by the last AA breakdown man to ditch them and switch to NGKs, which I did.
I know the sidevalve engine is not a performance beast(!) and it may not make much difference, but know there will be some informed opinions on this website!
1960 2 door with 1275 Midget engine - WOI 577
1952 MM convertible with original engine - MWD 305
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