Somerford Mini Ltd. Ordering Parts Using This Catalogue

External Engine - 848 and 997cc
No. Part No. Description Qty. Remarks No. Part No. Description Qty. Remarks
848 and 997cc Engine Identification
The 848cc A Series engine was the original engine in the Mini when the car was launched in 1959. It
continued in production until the cessation of the Mini Van, the last batches of which made it to
commercial fleet operators in early 1984. Like other Mini engines that continued in production after the
1970s, the 848cc engine received a timing chain tensioner pad at the end of that decade.
However it never got the strengthened cylinder block or the other ‘A Plus’ modifications wrought on the
998, 1098 and 1275cc engines - the 998 (which shared its block with the 1098) and 1275cc engines
being scheduled to have much longer production lives in the Austin Metro.1980s 848cc engines can
therefore only be easily identified by a bulge in the timing chain cover, giving away the fact that there
is a chain tensioner pad assembly inside. 848cc engines used with automatic gearboxes are different in
several respects to those used with manual; 848cc automatics ceased production in 1971.
In fact, the only other BMC/Leyland vehicles to use the 848cc engine were the Mini Moke, a handful of
early 1980s Metro Vans and the final batch of Austin A35 Vans built as AA patrol vans in 1968! The
latter was the only non-transverse 848cc A Series engine type ever produced, incidentally, while it would
be very unlikely indeed for you to find one of the other two transplanted into your Mini.
The 997cc A Series engine is most closely related to the 848cc unit from which it was directly developed
(which is why it is included with the 848cc engine in sections of this catalogue). It only saw use in one
model of Mini, the first incarnation of Mini Cooper, and was produced from 1961 to 1963. The only
other application of note for a 997cc A Series was in John Cooper’s ‘Formula Junior’ racing cars, from
which most of the components were borrowed for the Mini Cooper.
Engine serial number prefix codes are impor tant in identifying what you have in your car and
establishing which replacement parts to fit to it. The 848 and 997cc engine number prefixes used on
Mini engines are listed here for that reason. The engine serial number is stamped on a plate affixed to
the cylinder head mating face or ‘deck’ of the cylinder block, at the front of the engine towards the right
hand side, as you look at the engine in the car. Note that the last code letter before the serial number
itself always relates to the compression ratio of the engine: H for high compression, L for low
compression.
Factory reconditioned engines always lost their serial numbers in favour of an engine number plate
stamped with the appropriate part number for the intended application for each engine. In the absence
of an engine serial number on a factory reconditioned unit, this is the only means of identification - but
beware! Factory reconditioned engines were more often than not built up with whatever suitable
components were to hand; for example , new parts were usually plucked from the engine production line
and were therefore of the latest design. Reused components came from stocks of parts which would do
the same job, but w ere not necessarily the same design, all lumped to gether. In other words, parts used
in the rebuild were frequently incorrect in an historic sense for the engine being rebuilt.
848 and 997cc Engine Serial Number Prefix Codes 1959-69
8A/ 848cc Austin manual gearbox engines only up to engine no. 25000 (1959-60)
8MB/ 848cc Morris manual gearbox engines only up to engine no. 25000 (1959-60)
8AM/ 848cc Austin and Morris manual gearbox engines without closed circuit breathing from
engine no. 25001 (1960-69)
8AH/ 848cc Austin and Morris automatic gearbox engines without closed circuit breathing
(1964-69)
8AJ/ 848cc Austin and Morris manual gearbox engines with closed circuit breathing (1964-69)
8AK/ 848cc Austin and Morris automatic gearbox engines with closed circuit breathing (1964-69)
8WR/ 848cc Wolseley and Riley manual gearbox engines (1961-63)
9F/SA 997cc Austin and Morris Cooper manual gearbox engines (1961-63)
848cc Engine Serial Number Prefix Codes 1969-84
85H/ Engines from 1969 onwards
With the advent of 85H/ serial numbers in 1969, the codes became far more complex. 85H/ was
followed by a three digit number and either one or two letters . The number referred to the
transmission fitted (manual/automatic, type of gearchange, type of drive shaft joints, final drive ratio etc .),
the charging system fitted (dynamo or alternator), plus any unusual specifications (Police, Post Office or
other utility users, export market specific requirements).
The one or two letters following the three digit number referred to emission controls fitted (type of
crankcase ventilation, air intake system, evaporative loss control, etc .). Unfortunately with regard to the
848cc engine there are too many combinations of codes to list in the space available here, but if you
contact Somerford Mini with your full engine number we can ‘unpick’ the codes to tell you exactly what
specification your engine was built to.
BMC/Leyland/Unipart Mini 848 and 997cc Reconditioned Engine P art Nos.
8G13 848cc manual gearbox engine, with 1 3/8" tail diameter type crankshaft accepting oil-fed
primary gear bush (1959-62; replaces D.U. bush type)
8G28 848cc manual gearbox engine, with 1 3/8" tail diameter type crankshaft for Deva primary
gear bush (1962-63)
8G35 848cc manual gearbox engine, with 1 1/2" tail diameter type crankshaft for Deva primary
gear bush and warning light type oil filter head (1964-67)
8G45 848cc manual gearbox engine, with 1 1/2" tail diameter type crankshaft for Deva primary
gear bush and non-warning light type oil filter head (1964-80)
GSE1101 848cc manual gearbox engine; later ‘Gold Seal’ part number. Spec. as 8G45 (1964-80)
RKM1101 848cc manual gearbox engine; later ‘Silver Seal’ part number. Spec . as 8G45 (1964-80)
RKM1118 848cc manual gearbox engine; later ‘Silver Seal’ par t number. Spec. as 8G45; replaced
RKM1101 (1964-80)
BHM1307 848cc manual gearbox engine, with 1 1/2" tail diameter type crankshaft for Deva primary
gear bush and timing chain tensioner (1980-84)
8G52 848cc automatic gearbox engine without closed circuit breathing (1964-69)
8G53 848cc automatic gearbox engine with closed circuit breathing (1964-71;848cc automatic
discontinued after 1971)
8G18 997cc high compression engine, with 1 3/8" tail diameter type crankshaft accepting oil-fed
primary gear bush (1961-62; replaces D.U. bush type)
8G36 997cc high compression engine, with 1 3/8" tail diameter type crankshaft for Deva primar y
gear bush (1962-63)
8G29 997cc high compression engine, with 1 1/2" tail diameter type crankshaft for Deva primar y
gear bush (1963)
8G23 997cc low compression engine , with 1 3/8" tail diameter type crankshaft accepting oil-fed
primary gear bush (1961-62; replaces D.U. bush type)
8G37 997cc low compression engine, with 1 3/8" tail diameter type crankshaft for Deva primary
gear bush (1962-63)
8G30 997cc low compression engine, with 1 1/2" tail diameter type crankshaft for Deva primary
gear bush (1963)
There never was a differentiation made between open circuit or closed circuit breathing, nor between
dynamo or alternator fitment, on manual transmission reconditioned engines. The factory instructed that
the parts concerned (rock er cover, tappet cover, pulley etc.) should be swapped over from the old engine
to the new one as required. All factory reconditioned 848cc engines were high compression ratio units .
Rebuilt or Repaired Engine Assemblies
Somerford Mini Ltd. offers an engine rebuilding and repair service, courtesy of its workshop facility. We
can carry out repairs or rebuilds on late-model engines, but the extent of rebuilding on an early engine is
governed by - and sometimes restricted by - par ts availability.
Please contact us to discuss your Mini engine requirements - it would be helpful if you could supply us
not only the details of what’s gone wrong with your engine , but also the full engine number (if known)
and type (capacity, high or low compression, gearbox, breathing system, etc.). The more you can provide
us with,the better we can ascertain how we might possibly help you.
Gasket Sets
1 GUG49 GASKET SET, con version (‘bottom end set’)1 Manual gearbox models.
GEG254 GASKET SET, con version (‘bottom end set’)1 Automatic gearbox models.
Conversion gasket sets (often called ‘bottom end’ or ‘supplementary’ sets) include gaskets for the following:
water pump, front cover, tappet chest covers, front mounting plate, oil pump, oil filter head, engine to
gearbox joint and flywheel/torque converter housing. Washers, seals and O rings are included for the
following: priming plug, drain tap/plug, main bearing cap, front cover, tappet chest covers, distributor
housing and oil suction pipe. Note that the tappet chest cover gaskets included are the post-1966 rubber
type - customers requiring the earlier cork gaskets should purchase them separately.
EGS001 GASKET SET, full engine 1 Manual gearbox models.
The full engine gasket set includes the conversion gasket set listed above plus a cylinder head gask et set
(‘decoke’ or ‘decarbonising’ set) minus the head gasket itself, which should be purchased separately
according to the engine size.
External Engine Components
2 2K8169 PLUG, core, cylinder block 4
3 2K1345 PLUG, oil pressure release valve passage 2
4 12H1734 PLUG, oil gallery 2
5 ADP210 PLUG, oil feed 1 Automatic gearbox.
6 1B3664 WASHER, sealing 1 Automatic gearbox.
7 1A1964 RESTRICTOR, cam bearing oil feed 1
8 CAM150 STUD, cylinder head, long 4
9 CAM151 STUD, cylinder head, short 5
10 CHS2513 STUD, fuel pump drive aperture 2 1959-69.
CHS2515 STUD, fuel pump drive aperture 2 1969 on.
From 1959-69 the fuel pump drive aperture studs secured a blanking plate, plus the open circuit
breathing vent pipe (if fitted). From 1969 onwards, they secured the mechanical fuel pump. For
mechanical fuel pump fixing details, including the gasket (which is not the same as the blanking plate
gasket), please see the ‘Fuel Pumps - Carburetter’ section in the Fuel and Exhaust Systems area of the
Somerford Mini Catalogue.
Tel. 01249 721421 Fax. 01249 721316 www.somerford-mini.co.uk
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