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).
The causes and proposed lubrication-based solutions for camshaft squawks.
| Identifier | WestWitteringFiles\V\October1930-February1931\ Scan133 | |
| Date | 6th December 1930 | |
| BY.{R.W. Bailey - Chief Engineer} (struck through) FROM E.{Mr Elliott - Chief Engineer} C. to CG. WOH. HS.{Lord Ernest Hives - Chair} (struck through) C. to EP.{G. Eric Platford - Chief Quality Engineer} HS{Lord Ernest Hives - Chair}/GWH.{George W. Hancock - Head Chateauroux} (struck through) ORIGINAL P. 2. CAMSHAFT SQUAWKS. V7090. From results of observations and experiments it has been concluded that squawks are caused by torsional shudders in the camshaft set up by the maximum torque portion of the cam lift. This is aggravated by the cams lifting in pairs, and the worst cams for squawking are Nos. 10, and 12, at the free end of the shaft. It has also been concluded that an improvement in the lubrication would be beneficial, if not even an absolute cure. All of the cams as a matter of fact shew markings of a character indicating insufficient lubrication. The ideal scheme would be to enclose the camshaft in a tube filled with oil, but as this is not practicable on P. 2. a scheme of separate oil cups has been evolved, enclosing and flooding each cam with oil. This scheme has been made applicable to existing chassis, and if found successful can be applied in simpler form to future production. We attach herewith Loc. 2847. giving all the information necessary. Oil is supplied to the camshaft by coupling up the central camshaft bearing with the intermediate oil pressure system. It is necessary to use a bored up camshaft, but the bore can be reduced in diameter if considered to be easier thereby to produce. So far as we can see it will be possible to fit up this scheme on an engine in place in a chassis, without removing the crankshaft, but naturally the valve gear must be stripped, and the bottom half of the crankcase removed. E.{Mr Elliott - Chief Engineer} [Stamp: RECEIVED 8 DEC 1930 HS{Lord Ernest Hives - Chair}] | ||