Riley 1½ Modifications



36S/10001   Commencing number.


10157                     Serrated clutch bottom shaft.


10632                     Clutch pedal stop and second pull-off spring added.


110O0                    Clutch plate with black and green springs (engine A1246).


11304                     Hydraulic carburettor dashpot fitted.


11360                     Modified centre bearing to torque tube.


11782                     Larger roller on brake compensator.


37S/12053            Horns moved to wing stays.


12440                     Stitched roof lining.


12560                     Narrow gearbox tunnel; floorboards modified to fit.


12646                     Machined differential box.


12800                     Strengthened lower suspension struts.


13127                     Stiffener to front number plate.


13925                     Mk.II Lucas headlamps and modified cowl.


38S/14544             RYZ clutch plate and light bowl assembly.


14565                     Bolt replaced in trunnion housing.


14581                     Clamp bolt on torque tube deleted.


14685                     2½ litre swivel arms fitted to the 1½ litre model. 

                                            Reason: to improve steering (5" longer).


14740                     Longer anti-roll bar brackets.


14903                     Semi-hydrostatic HNS.1 brakes, lined MR.41, added.


15001                     Second series commencing, including Ley's crown gear housing.


15072                     Second series body (lower front floor).


15151                     Internal bonnet locks.


15306                     Extruded door surround rubbers,


15355                     Hand dipper-switch.


15454                     High trunnion "B" member lowered.


15464                     Trunnion member lowered to suit lower floor in 2nd sanction  body


39S/16156          Softer rubbers fitted to trunnion members.  Reason: to overcome

                      vibration (5 round rubber rings, 1 square edge ring).


16223                     PV6 type rear shock absorbers fitted in place of the PR6 type,

                      H5079 rear shock absorber 0/S, PV6/56 type SA133-70 replaces

                      PR6/56 YD5790. H5080 rear shock absorber N/S, PV6/57 type

                      SA133-69 replaces PR6/57 XD5791.


16692                     Modification to the kingpin bushes, which is an increase in lengh

                      of the steel bush, pt no. A26l8 and the shortening of the brass

                      bush, Pt no. A2525, to prevent grease reaching and damaging the

                      the rubber bushes.  The new part numbers for the bushes are:

                      A2712 bronze bush, A2718 assembly of screwed bush for kingpin.


From October 1950:

                      Introduction of carburettor jet with two feed

                      holes of . 140" diameter replacing jet with 10 feed holes of

                      .093" diameter.  Jets are interchangeable, the old part no. is



From 1st November, 1950:               

                      Introduction of a modified door lock incorporating a stronger bolt,

                      spring, pt. no. RS-41-349. When modifying earlier locks, in addition to

                      the stronger spring, pt. no. RS-41-349, the existing bolt assemblies must be

                      replaced by the following parts:

                      Front door lock - (with only one stud on the bolt assembly

                      acting between the operating lever and the spring reaction

                      lever) LH side new bolt assembly, pt. no. L3321/A RH side new

                      bolt assembly, pt. no. L3321/B

                      Rear door lock - (with 2 studs positioned across the bolt

                      assembly) LH side new bolt assembly, pt. no. L3320/B RH side new

                      bolt assembly, pt. no. L3320/A


39S/17120 ,124, 126-128, 130-135, 145-159, 161-193, 195-209:

                                 1½ litre R.H.D. with new body trim and

                                 door cappings.   Concealed visors, new floorboards and gearbox

                                 cover but fitted with old type facia and round instruments.


(Note these chassis series have gaps).


17010          012, 125, 194, 210 onwards: Common bodies 2½  and 1½ litre, new

                      trim, etc. and with new (1950) style facia and square instruments.


17210          Wings indented to take standard headlamp body. Cars now filled at works with

                      Lockheed no. 33 brake fluid.  For service purposes Girling or Lockheed 33 brake

                      fluid may be used.

                      It has been confirmed that the Girling brake fluid is also suit-

                      able for Arctic conditions, either will mix.


17314          5/32" hole drilled in top of casing, 8" off centre on RH side

                      replaces hole drilled in filler plug.  New filler plug, no.

                      500004, or blank off hole in existing plug. 

                                 Reason: improved venting.


17420          Taper type rebound rubbers replace square type.  New pt. no.


                                 Reason: improved type.

                      Introduction of front suspension lower links with longer web

                      plates (and replace all older type links). 

                                 New part numbers:

                      500043        bottom link assembly RH (1 pair comprising)

                      500045        bottom link assembly rear RH

                      500047        bottom link assembly front LH

                      500044        bottom link assembly LH (1 pair comprising)

                      500046        bottom link assembly rear LH

                      500048        bottom link assembly rear LH

                      Reason: improved type.


19337                     Scuttle ventilator modified by moving the pivot from the central

                      position to the extreme rear.  Reason: to increase opening and

                      improve interior ventilation.


40S/18484          Front suspension no. 1337.  Front brake lining shoes shortened by 1" at the                                  leadingedge on both leading and trailing shoes.  The linings have been

                                 re-riveted with two rivets at these points.

                                 New parts:

                                 300120 front brake and shoe lining assembly  4 off

                                 300121  lining  4 off

                                 300122  rivet  4 off

                                 Reason: to prevent front brake grab.


18562          Floorboards, gearbox cover and ramp plate have been modified to a

                      flanged and bolted down type in place of the previous clip down

                      gearbox cover.  All floorboard, ramp plate and gearbox cover flange

                      joints are now made with a strip of 3" wide Prestik jointing

                      material.  This material is supplied in rolls suitably cut off and

                      stuck to all floorboard and gearbox cover edges, the parts fitted on

                      top and the bolts pushed through the Prestik during assembly. 

                      Redundant holes in ramp plate (on cars without heater fitted) are

                      covered up with leather cloth fixed with Bostik "C" adhesive.  An

                      additional steering column grommet is added to steering column on

                      the front face of the bulkhead.  The ramp plate sound baffle board

                      and felt backing are done away with and now padded carpets are

                      added.  Full modification details from the factory.


18867          Brake pipes re-run to allow hoses to be fitted behind the suspension

                      links instead of in front. 

                                 New part numbers:

                      A7004  front suspension assembly

                      500193 assy of pipe, tee piece to 0/S hose R.H. Drive

                      500194 assy of pipe, tee piece to N/S hose R.H. Drive

                      A7007  front suspension assembly

                      500218 assy of pipe, tee piece to O/S hose L.H. Drive

                      500219 assy of pipe, tee piece to N/S hose L.H. Drive

                      500188 assy of hose bracket R.H. and L.H. Drive

                      500189 assy of hose bracket R.H. and L.H. Drive

                      Reason: to prevent chafing of hose on rim of road wheel.


18924          Introduction of rear telescopic shock absorbers type DA39 replace

                      piston type shock absorber type PV6 necessitating the fitting of a

                      new exhaust tailpipe and expansion box assembly. 

                                 New part nos:

                      500158 rear shock absorber (2 off)

                      D5636  washer (4 off)

                      5W108Z  spring washer (4 off)

                      FN108Z nut (4 off)

                      PW108Z plain washer (2 off )

                      500036 assy of shock absorber mounting bracket (2 off)

                      500213 shock absorber bracket RH (1 off)

                      500214shock absorber bracket LH   (1 off)

                      500172 assy of expansion box and pipes (1 off )

                      500169 tailpipe, rear (1 off)

                      Reason: improvement to design.


41S/19498            Girling type CDR5 front telescopic shock absorbers with 1½" bore

                      replace Girling type DA/6/5 with 1" bore.         

                                 New part numbers;

                      500306 front shock absorber (2 off)

                      500110 anchorage sleeve (2 off )

                      5O0113 nut for anchorage sleeve (2 off )

                      FB108/18N  bolt ½"BSF x 2¼" (additional) (2 off)

                      500111 front shock absorber bottom lug BH (1 off)

                      500112  front shock absorber bottom lug LH (1 off)

                      500114 dowel pin - bottom wishbone  (2 off)


19453                     Export LHD as above


19661                     New type steering wheel pt. no. 500677 introduced incorporating

                      a collet type clamp with fluted lock ring in place of split clamp

                      with bolt and lock nut.  Reason: improved design.


42S/20060   Air scoops pt. nos. 500531 (RH) and 500532 (LH) of swivelling type

                      are now available for attachment to the front doors and are fitted

                      as standard from the above chassis number.  Reason: improved

                      ventilation control.


RME/20505          Introduction of full hydraulic brake gear.

                      Introduction of front hubs incorporating ANF threaded studs.

                      Introduction of front suspension unit having twin leading brake


                      Introduction of hypoid rear axle with open propeller shafts and

                      hubs incorporating A.N.F. threaded studs and stronger rear road

                      springs.  Hypoid 90 oil now used for the rear axle and gearbox

                      as well.

                      With the introduction of full hydraulic brake gear the front wheel

                      cylinders are now 7/8" diameter in place of 1" wheel cylinders.


Engine Nos.


A3100         Static balanced clutch and flywheel.


A7449         New type starter (Lucas 25521 A) without switch, pt. no. R1556. New ST.950                           solenoid switch on   bulkhead.


A9241                    Piston and bore size changed from millimetre to inch measurement.                                        Pistons now marked with the correct size of the cylinder bore for which they                                 are suitable.  The markings on the block should correspond accordingly.


A9490                    Guide for dipstick fitted to crankcase.  New pt. nos:

                      Dipstick       166088)

                      Dipstick ferrule  13454 / 166089

                      Dipstick washer   13455 / 166089 

                      Dipstick guide    166085

                      Reason: improvement to design.


A10311     Introduction of inlet camshaft pt. no. 166119 and exhaust camshaft pt. no. 166120                       with no. 6 form cams (XPJM type). The timing chain and the camshaft chain                              wheels are now marked for ease of timing.  Three bright links on the timing chain                        register with T marks on chain wheels.  Tappet clearance is now 0.15" hot.

                      Reason: improvement to design.


A10292      Oil pipe - engine to adaptor pt. no. 166349 replaced pt. no. H7132. 

                      Reason: fitting of flexible pipe to prevent chatter in oil gauge.


A10614      Introduction of improved type valve rockers, tappets, tappet rods, etc. 

                      Tappet rod pt. no. 166225 (8 off) replaces pt. no. R136 (8 off), tappet assembly

                      pt. no. 166335 (8 off) replaces pt. no. 166095 (8 off),

                      valve rocker RH pt. no. 166227 (4 off) replaces pt. no. R1418 (4 off),

                      valve rocker LH pt. no. 166228 (4 off) replaces pt. no. R1417 (4 off),

                      rocker ball pin pt. no. R1394 (8 off) and adjusting nut pt. no. 10455 (8 off)

                      are replaced by tappet adjusting screw pt. no. 166229 (8 off) and

                      Locknut pt. no. FN205 (8 off). 

                      Reason: improvement to design.


RMA/11941   Introduction of suppressor terminals on plugs pt. no. 163440

                      replacing spark plug terminal pt. no. 168550.

                      Reason: to comply with latest requirements for ignition suppression.


RMA/12280  Introduction of valve spring (outer) pt. no. 166553 replacing

                      valve spring (outer) pt. no. R647.  Reason: to improve valve

                      spring crash which is too low with the 8 x 41 axle ratio.


Gearbox Nos.


BC449 approx. (17-6.52): Introduction of gearbox mainshaft pt. no. 166238

                      with an indent added and an additional retainer ball in the synch

                      hub.  The seven balls will be retained by peening into the hub

                      to prevent any chance of ejection. 

                                 New parts:

                      Mainshaft pt. no. 166238  (1 off)

                      Mainshaft sliding hub assy SA166353  (1 off)


                      Sliding hub top and 3rd 166239  (1 off)

                      Sliding hub cone 19472  (2 off)

                      Spring 194131   (5 off!

                      Spring 166240  (1 off)

                      Ball 1279   (7 off)

                      Reason: to prevent hub working forwards and backwards while running in gear

                      and wearing out against the mating cone.