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).
Flywheel and clutch issues, detailing slipping caused by over-lubrication and subsequent modifications.
| Identifier | ExFiles\Box 5a\2\ 02-page345 | |
| Date | 18th December 1930 guessed | |
| -6- freer from joggles. This may be due to the variation of the friction loads. This will be verified during the remainder of the test. There has been no wobbles at either high or low speeds. On the extreme left lock a slight sticking has occurred. The steering is not considered to be too light for the high speeds and has been light for shunting, slow speeds etc. Self centreing is O.K. FLYWHEEL AND CLUTCH to LCF G.54364 - LeO 1830/1 - G.L.435. New modified Flywheel & Clutch, incorporating separate Gear ring, revised lightened type, stronger springs, damper plate, automatic lubrication spigot bearing. The clutch during the first 2,000 miles was very smooth in taking up the drive and was generally very good. At 2,500 miles slight slipping was noticed upon acceleration. This slipping increased until at 5,000 miles it would not at times take up the drive on any slight incline. The slipping varied in intensity from time to time. The clutch also seized up with heavy traffic work when several slipping engagements were made. It has been dismantled and a thorough examination made to find the cause of the failures. SLIPPING. This has been caused by the over lubrication of the automatic lubrication to the spigot bearing. The fault being no oil catcher fitted to prevent oil being thrown on to the fabrics. These were saturated with oil. The design is such that excess oil must pass the fabrics before reaching the drain holes. A modification will have to be made on similar lines as the Phantom II to collect excess oil. There is no lubrication reaching the bronze bearing of the clutch plate. This showed definite signs of tightening up. We have before erecting the clutch made the following modifications. The oil catcher in the gear box had a feed hole of .025". We have plugged this up and drilled a .125" hole to reduce the supply of oil. To lubricate the bronze bearing of the clutch plate, We have drilled a .105" hole in the clutch shaft approx. in the centre of the bearing. This will then be automatically lubricated as well as the spigot bearing. The seizing up of the clutch is due to the heat generated, expanding the flywheel spigot for the trunnion sleeve. We had the clearance of the sleeve increased to .004" before the test started, as this clearance has previously cured this complaint. The symptoms of this failure was that the trunnion was not in alignment with the spigot. We have eased and polished the spigot. There is no lubrication to the trunnion sleeve but this feature had been taken up with the D.O. before this failure. The clutch fabrics have been thoroughly washed down with petrol before erecting the clutch. Any improvement derived by the setting back of the flywheel is questionable. | ||