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).
Ongoing development and testing of pistons and liners for the Phantom III engine.
| Identifier | ExFiles\Box 94\5\ scan0116 | |
| Date | 8th February 1936 | |
| Sft.{Mr Swift} Sft{Mr Swift}/Mr Goodall. c. E.{Mr Elliott - Chief Engineer} c. BY.{R.W. Bailey - Chief Engineer} from Mx.{John H Maddocks - Chief Proving Officer} Mx.{John H Maddocks - Chief Proving Officer}1/T.8.2.36. PHANTOM III PISTON DEVELOPMENT. Although we have met with some success in using specially ground pistons with the use of short liners, the position cannot be considered entirely satisfactory. It is important therefore that we push on with the test of the longer "gashed" liner which will give more support for the piston at the bottom of the stroke. We propose to fit the first set of Experimental "gashed" liners which came into the Works on the 6th inst. into Experimental Engine No.5. in conjunction with sealing rings as follows (1) Upper or water seal ring to be DTY.10.E.87908,pink in colour, for purpose of identification, (2) Oil Seal Ring to be D.Specification E87743 - this is a black ring. The question of whether it is considered advisable to hone the liners in position after fitting, or before they are inserted in the crankcase, is not yet settled. For the purpose of this test I shall be quite satisfied to have them honed before fitting, as has been done on our previous tests. With regard to the pistons - will you please arrange to produce a set for this test on which the bottom load diameter is to a dimension of 3.250, this dimension to be continued parallel for 1/2" up the piston skirt, as per amended grinding print herewith. The pistons to be complete with rings - the scraper ring to be the slotted type. Also a set of gudgeon pins with the end buttons modified as per blueprint E87811. It is important that we run this test with marine type rods. I have made enquiries to see whether we can obtain a set from the Experimental Dept. Our previous testing has been done on the strap type rod wiyh lead bronze bearings, and as these are now obsolete, it would be entirely wrong to carry out this important piston test with any other than the standard rods. With regard to your suggestion, we shall be very glad to have the cooperation of an engine bench fitted, when fitting the liners and assembling the engine. Mx.{John H Maddocks - Chief Proving Officer} | ||