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).
Letter discussing engine issues like valve burning, corrosion, and detonation in relation to leaded fuel, comparing notes with Curtiss Wright.
| Identifier | ExFiles\Box 173\1\ img098 | |
| Date | 25th January 1934 | |
| U.S.A. Rm.{William Robotham - Chief Engineer} and RHC.{R. H. Coverley - Production Engineer} From Hs{Lord Ernest Hives - Chair}/Lov.{Mr Lovesey} We were very interested in your letters re. visit to Curtiss Wright and the General position of leaded fuel and lead bronze. LEADED FUEL. You have no doubt by this time received our report on valve burning on T.E.L. and will see that their results very closely match up with our experience. You will be interested to hear that apart from completing a 100 hrs. official Type Development we have now completed 100 hr. Official Type Test on 4 c.c. T.E.L. at an endurance power giving 120 lbs. M.E.P. Rated M.E.P.147. We note your remark that the Conqueror has run up to 147 M.E.P. on Type Test and we assume it must have had at least 3 c.c. lead to do this. This is the same M.E.P. as the endurance power of our moderate supercharged Goshawk. Has the "Conqueror" gone to the butt-ended liner purely on account of Ethylene Glycol?. Apart from valve burning have they experienced much cold corrosion of the valves with lead?. We have just had a good example of this on some valves taken from the Phantom which operated the blower rig and has been running on ordinary Pratts Ethyl - the head and underside of valves were badly pitted as if they had been immersed in sea water. Is it found over there that stelliting the faces - or any other treatment - prevents this as distinct from the burning trouble. DETONATION. How do they reckon detonation on their engines? Is the destructive effect of this accompanied by audibility in the way we experience. We know that if the audibility exceeds a certain amount - by listening at a distance - destruction of the top ring occurs - well before trouble with the piston. With the Curtiss Conquerors steel cylinder head they may be able to stand a larger amount of detonation and assume the first signs of trouble would be the piston. Should like to know any further information on this point. Are the liquid cooled engines further removed from detonation than air cooled - in other words what extra M.E.P. can the liquid cooled engine operate above the air cooled - if any. | ||