26-02-2019, 12:58 AM
(This post was last modified: 26-02-2019, 03:36 AM by Tony Press.)
This applies to both the 'Front Bearing Puller' and 'Rear Main Bearings' discussions.
Taken from a 60 year old SKF Catalogue-
The British Standard for both Ball and Roller Bearings-
Size Tolerances for bearings
Bore over 1" - 0.0003" to + 0.0002"
Outside diameter 2" to 3" - 0.0005" to - 0.0010"
Outside diameter 3" to 5" - 0.0008" to - 0.0013"
The SKF Shaft Fit recommended for normal and heavy loads such as internal combustion engines
Cylindrical Roller Bearings up to 1 1/2" shaft diameter - k5i
Ball Bearings up to 4" shaft diameter - k5i
Tolerances k5i for 1 1/8" shaft diameter Ball and Roller Bearing + 0.0002" to + 0.0005"
Tolerances k5i for 1 1/4" shaft diameter Roller Bearing + 0.0003 to + 0.0007"
The SKF Housing Fit recommended for normal and heavy loads such as crankshaft main bearings, direction of loading indeterminate-
Ball and Cylindrical Roller Bearings K7i
Tolerances K7i for housing diameter 2 13/16" - 0.0013" to - 0.0001"
Tolerances K7i for housing diameter 3 1/8" - 0.0016" to - 0.0003"
The bore and housing sizes shown are for SKF Ball Bearing RMS 9, Angular Contact Ball Bearing AMS 9 and Roller Bearing CRM 9 fitted to the Light Shaft and later heavy shaft and CRM 10 from the heavy shaft.
Longbridge could have opted for a looser shaft fit for the front ball/roller and later angular contact bearings to aid assembly, relying on the clamping force of the front crank handle dog to stop any rotation. Given that most shafts don't seem to have suffered from much inner ring 'creep' here this would have been acceptable.
The rear bearing fit is possibly not heavy enough given the number of Light Shafts that had been knurled in the 60's (a very short lived solution)
Sorry for the long post.
Tony.
Taken from a 60 year old SKF Catalogue-
The British Standard for both Ball and Roller Bearings-
Size Tolerances for bearings
Bore over 1" - 0.0003" to + 0.0002"
Outside diameter 2" to 3" - 0.0005" to - 0.0010"
Outside diameter 3" to 5" - 0.0008" to - 0.0013"
The SKF Shaft Fit recommended for normal and heavy loads such as internal combustion engines
Cylindrical Roller Bearings up to 1 1/2" shaft diameter - k5i
Ball Bearings up to 4" shaft diameter - k5i
Tolerances k5i for 1 1/8" shaft diameter Ball and Roller Bearing + 0.0002" to + 0.0005"
Tolerances k5i for 1 1/4" shaft diameter Roller Bearing + 0.0003 to + 0.0007"
The SKF Housing Fit recommended for normal and heavy loads such as crankshaft main bearings, direction of loading indeterminate-
Ball and Cylindrical Roller Bearings K7i
Tolerances K7i for housing diameter 2 13/16" - 0.0013" to - 0.0001"
Tolerances K7i for housing diameter 3 1/8" - 0.0016" to - 0.0003"
The bore and housing sizes shown are for SKF Ball Bearing RMS 9, Angular Contact Ball Bearing AMS 9 and Roller Bearing CRM 9 fitted to the Light Shaft and later heavy shaft and CRM 10 from the heavy shaft.
Longbridge could have opted for a looser shaft fit for the front ball/roller and later angular contact bearings to aid assembly, relying on the clamping force of the front crank handle dog to stop any rotation. Given that most shafts don't seem to have suffered from much inner ring 'creep' here this would have been acceptable.
The rear bearing fit is possibly not heavy enough given the number of Light Shafts that had been knurled in the 60's (a very short lived solution)
Sorry for the long post.
Tony.