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).
Cause and potential solution for knocks in Phantom II engines.
| Identifier | ExFiles\Box 13\2\ 02-page172 | |
| Date | 16th December 1933 | |
| x7090 To Mr. BY.{R.W. Bailey - Chief Engineer} HS.{Lord Ernest Hives - Chair} KP. MX.{John H Maddocks - Chief Proving Officer} BR.{T. E. Bellringer - Repair Manager} from E.{Mr Elliott - Chief Engineer} E.12/HP.16.12.33. Knocks in Phantom II Engines. Your memo Hd{Mr Hayward/Mr Huddy}20/MW.15.12.33 confirms our conversation re chassis 106-MY and our proposal to reduce the camshaft end play to .004" thou. maximum. We should undoubtedly expect a knock to be set up of the nature you describe with excessive end play due to the anti torque of the camshaft reacting on the helical angle of the wheel teeth, and this anti torque would be at a maximum under the conditions of running you mention, and would tend to disappear when the throttle is opened sufficiently to produce some gas pressure load on the exhaust valves. We think it should be possible with the adjustment washers provided to tighten up this clearance as indicated. E.{Mr Elliott - Chief Engineer} | ||