Prototype Mini Automatic 1962

(Re-posting this topic in the more relevant archive section as it was long lost in general Mini Chat - MAB)

 

Underbonnet photo of the first automatic Mini prototype in 1962
 

In 1965 the world's smallest automatic gearbox arrived, specially developed by Automotive Products. All parts were housed in the sump and uniquely lubricated by circulating the engine oil. Announced in 1965 but because of many problems only became available in quantity from 1967 making Mk1 versions very rare. Early testing revealed that oil surge in the sump under cornering could cause oil starvation of the torque converter and sky-high engine revs. To compensate for this failing the oil pump was moved to the centre of the sump and oil capacity was increased.

Final assembly problems also arose and manufacture of the gearboxes was transferred to clinically clean, dust free rooms to ensure a dependable assembly of the unit with its numerous hydraulic valves.

The design itself put all known hydraulic boxes in the shade and to make the most of the engine's meagre output, gave four speeds as against the three of other automatics current at the time.

A mechanical control ensured gear selection according to load when in automatic mode, and there was also a kick-down working directly off the throttle pedal. To compensate for the usual auto power losses on an 850cc, the compression ratio was increased to 9:1 and a larger SU carburettor with inlet manifold was fitted. (I can remember searching for the auto Mini's in scrapyards in the 1970's to aquire these parts for upgrading our 850cc manual cars!)

Useful AP Automatic Technical Information:
http://members.tripo...erica/id72.html

Mini-1100 AP Automatic Transmission:
http://www.austinmem...-105/index.html

Automatic Mini Register:
http://autominiregister.proboards.com/

 

I have been told by an ex-BMC/BL worker that apparently there was a man in Longbridge who's sole and only job was to mate 7 A-series engines and AP autoboxes together each and every working day!

Edited by mab01uk, 17 March 2017 - 07:43 AM.

BMC Pathe film on factory build of the Mini/1100/1300 Automatic Gearbox

 

Does the sound work for you all on the vid above?

No sound unfortunately.......but the film is easy to follow without audio and has very detailed close up shots on the factory build up of an A-Series automatic engine and AP transmission.

Great vid that one, thanks for posting up the Link mab01uk.

 

Many a budding engine builder I think could learn a bit from that, one thing I saw a LOT of was check, check, test and check - each and every part. There were NO short cuts anywhere in that production line.

 

Also of interest was few fitted with (Pollution) Air Pumps.

Did you find any in the scrappiest ? Great post by the way it amazes me the knowledge you have
May I ask are you on the mk1 forum

Did you find any in the scrappiest ? Great post by the way it amazes me the knowledge you have
May I ask are you on the mk1 forum

 

Mini Autos were often found in the scrapyards back in the 1970's so we found quite a few that donated their larger SU carb to upgrade our smaller carbed manual 850cc Mini's and without the insurance penalty of twin SU's for young drivers.

 

Yes I am also sometimes on the Mk1 Forum which is a great resource for early Mini's and have also donated some period info to the main Mk1 Performance website over the years:-

http://mk1-performan...k/mk1_index.htm

I thought so are you the chap who's just bought his son a cool clubby estate

That would be Mark (mk1) the owner of the forum if you are referring to this post. 

http://mk1-forum.net...php?f=6&t=15969

 

mab01uk has the same username on both forums

http://mk1-forum.net...ewprofile&u=141