From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Failures and modifications related to steering and transmission components.
| Identifier | ExFiles\Box 135\2\ scan0186 | |
| Date | 29th September 1943 guessed | |
| -2- STEERING. Steering Pendulum Lever Failure. The Pendulum Lever on 3.B.50 failed at 73,000 miles and consequent upon this failure all other Pendulum Levers have been examined and in the majority of cases found cracked. A separate report has been issued on this subject. The question of design modification is now being investigated. Steering Cam Failure. We have had four failures of the Steering Cam on 10.B.V. at 30,000 miles, 4.B.50 at 13,000 miles and 30.G.VII at 64,000 miles and 128,000 miles. At 128,000 miles 30.G.VII steering was fitted with a new Cam with a deeper case hardening and at the moment this has run approximately 7,000 miles. Steering Nibbles. We have reached the conclusion that for cars of the B.V. and B.50 type we do not wish to fit 7" tyres as they have an adverse effect upon steering, causing nibbles and a tendancy to wobble. This also raises the question of type wear. B.V.'s and B.50's fitted with new 6.50 x 16 tyres are perfectly alright, but as the tyres wear, so the steering begins to wobble, until with a 75% worn tyre the steering becomes unpleasant. On the other hand a 7" tyre will start steering wobbles at the first sign of wear. TRANSMISSION. Clutch Pressure Plate. We had three Clutch Pressure Plates fail on 30.G.VII due to the plates cracking at 64,250 miles, 71,650 miles and 72,550 miles, and one failed on 4.B.50 at 23,350 miles, also due to cracking. After a new plate had been fitted to 4.B.50 we still had symptoms of clutch slip and we therefore removed the "blue" pressure springs fitted, each at a poundage of 110 - 120 lbs and replaced them with "red" pressure springs with a poundage of 150 - 155 lbs. This cured the clutch slip and did not appear to affect the loading of the pedal. Unfortunately, 4.B.50 car was taken off the road shortly afterwards and a further set of "red" springs were then fitted to 30.G.VII. This car has now completed 39,000 miles with these springs and no trouble has yet been experienced with the Pressure Plate. We attribute the failure of the Pressure Plates to Clutch slip and consequent overheating of Pressure Plate. -continued- | ||