Item | Spec to Spec | Engine No to Engine No | Part No | Replaced By |
| Breather | 51L to 61L | N/A | AJ3A | N/A |
| Breather | 62L to 75L | up to 43364 | 3106C | 10-2-245C |
| Breather | 76L to 103L | 43365 to 229685 | 3118C | 10-2-245C |
| Breather | 104L to Date | 229686 to Date | 10-2-245C | N/A |
| Camshaft | 51L to 69L | N/A | J31 | N/A |
| Camshaft | 70L to Date | N/A | 3151C | Current |
| Camshaft End Cover | to 69L | N/A | J27 | N/A |
| Camshaft End Cover | 69L to 75L | to 43364 | 3152 | 3160 |
| Camshaft End Cover | 76L to Date | 43365 to Date | 3160 | Current |
| Carburettor | 51L to 69L | N/A | L65C | 5465C |
| Carburettor Inverted input type | 51L to 71L | to 31123 | 5450C | 5465C |
| Carburettor Closed Petrol Chamber type | 72L to 74L | 31124 to 33034 | L65C | 5465C |
| Carburettor Adjustable Air type | 75L to 84L | 33035 to 219810 | 5465C | 5466C |
| Carburettor 500rpm type | 85L to Date | 219811 to Date | 5466C | Current |
| Carburettor 600rpm type | 85L to Date | 219811 to Date | 5467C | Current |
| Connecting Rod | 51L to 86L | N/A | 5121C | N/A |
| Connecting Rod | 101L to Date | N/A | 5-1/D5CL | Current |
| Connecting Rod Dipper | 51L to 74L | to 33034 | 3126 | 5/16" Whit Tubular |
| Connecting Rod Dipper | 75L to 82L | 33035 to 215999 | 3127 | 1/4" Whit Solid |
| Connecting Rod Dipper | 83L to 86L | 216000 to Date | 3130 | 5/16" BSF Tubular |
| Connecting Rod Dipper | 101L and 102L | to Date | 5-1/D12 | 5/16" BSF Tubular |
| Connecting Rod Dipper | 103L to Date | to Date | 8-4-13C | 5/16" BSF Solid |
| Crankcase | 51L to 52L | N/A | L1 | N/A |
| Crankcase | 53L to 69L | N/A | L1A | N/A |
| Crankcase | 71L Only | 30175 on | 3101 | List 362 |
| Crankcase | 72L to 74L | N/A | 3470 | List 362 |
| Crankcase | 75L to 86L | 33035 on | 3571S | List 362 |
| Crankcase | 101L to 102L | N/A | 5471 | List 363 |
| Crankcase | 103L to Date | N/A | 4/473 | List 363 |
| Crankcase door | 51L to 61L | N/A | 3100 | Current |
| Crankcase door | 62L to 75L | to 43364 | 3102 | 5-1/B19 |
| Crankcase door | 76L to Date | 43365 to date | 3100 | Current |
| Crankshaft | 51L to 69L | N/A | L21 | N/A |
| Crankshaft 1¾" | 70L to 86L | N/A | 3111 | N/A |
| Crankshaft 1¾" Lister-Bruston direct coupled sets | 70L to 86L | N/A | 56111 | N/A |
| Crankshaft 2" with Pinion | 101L to Date | N/A | 5-1/E101C | Current |
| Main Bearing Split type | 51L to 86L | N/A | 3265/6 | N/A |
| Main Bearing Bush type | 101L to Date | N/A | 5-1/B4A | Current |
| Main Bearing Housing Split type | 70L to 85L | N/A | 3261/2 | List 071 |
| Main Bearing Housing Split type | 86L Only | N/A | 3661/2 | List 071 |
| Main Bearing Housing Bush type | 101L Only | N/A | 5-1/B26 | 5-1/B69 & B70 |
| Main Bearing Housing Bush type | 102L to Date | N/A | 5-1/B69 | List 071 |
| Cylinder with Integral Head | to 73L | to 32644 | 5131 | Various |
| Cylinder with Integral Head | 74L to 77L | 32645 to 53659 | 5196 | Various |
| Cylinder, without head Petrol, Paraffin, Gas | 82L to Date | 53660 to Date | 5530C | Various |
| Combustion Head Petrol | 82L to 83L | 53660 to 68471 | 5534P | 5539PC |
| Combustion Head Petrol Tank Cooled | 83L on | 68472 to Date | 5539PC | Current |
| Combustion Head Paraffin Tank Cooled | 80L on | 68472 to Date | 5531K | Current |
| Combustion Head Petrol Hopper Cooled | 80L on | 68472 to Date | 5538P | Current |
| Combustion Head Paraffin Hopper Cooled | 80L on | 68472 to Date | 5545K | Current |
| Combustion Head Gas Tank Cooled | 80L on | 68472 to Date | 5535G | Current |
| Flywheel | Start to 86L | N/A | 5161 | 2 fitted |
| Flywheel 25" x 3¾" x 1¾" Bore | Start to 86L | N/A Lighting Plant Flywheel | 5610 | 1 + 5609 |
| Flywheel 25" x 3¾" x 1¾" Bore | Start to 86L | N/A Lighting Plant Flywheel | 5609 | 1 + 5610 Coupling Facings |
| Flywheel 24" x 3½" x 2" Bore | 101L to Date | N/A | 5-1/E4 | Current |
| Flywheel 25" x 3½" x 2" Bore | 101L to Date | N/A Lighting Plant Flywheel | 5-1/E33 | Current |
| Flywheel 25" x 3½" x 2" Bore | 101L to Date | N/A Lighting Plant Flywheel | 5-1/E32 | Current Coupling Facings |
| Magneto Bosch Trip type | 51L to 56L | N/A | 22 | List 97 |
| Magneto Lucas Trip type | 57L to 69L | N/A | CK5 | List 97 |
| Magneto Lucas Rotary type | 70L to 102L | to 221649 | CK1 | List 97 |
| Magneto See Mag Listing for Mag Types | 103L on | 241490 to 243107 | KP1 or RS1 | List 97 |
| Magneto | 103L to Date | 243108 to Date | RS1 | Current |