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).
Chassis 93-NK after completing 15,447 miles.
| Identifier | ExFiles\Box 71\4\ scan0220 | |
| Date | 20th May 1925 | |
| R.R. 493A (50H) (D.B. 175 25-9-24) J.H.D. EXPERIMENTAL REPORT. Expl. No. REF: Hs{Lord Ernest Hives - Chair}/GWH{George W. Hancock - Head Chateauroux}2/Crn 20.5.25 C O P Y. To Hs.{Lord Ernest Hives - Chair} from G.W.Hancock. REPORT ON CHASSIS 93-NK AFTER 15,447 MILES. ENGINE. Engine power good and smooth. Compressions even. Examination of pistons shews even lubrication, but on the heavy side. Valves and fittings to E.2217.B. - these are O.K. We have ground in these valves twice during the test. There is already a fair amount of carbon deposit on piston heads. Modified cast iron choke valve in down take pipe to LeC.2035 - we have had no trouble with this since our last report. Carb. butterfly throttle E.73166/7/8 - this has stuck open on two occasions. We stated in our last report that this was due to very fine sand getting on to spindle. We have verified this on dismantling carburetter. There is a very fine crack in the hot-spot induction pipe at the bottom corner close to flange where carburetter is bolted up. After cleaning butterfly spindle we have had no trouble with sticking. Controls to Sch.625 - slight amount of slack has developed in these, but not excessive. We found the ball end on the relay lever had worked loose. We have swelled out the end and tightened this up again. As previously stated, we are now using the boilers and the drivers are of the opinion that the explosions are slightly worse now on retard than they were. Front engine suspension tube to LeC.2027 - this is still quite O.K. Modified throttle governor spring to Sch.632, using spring E.5925 - this is still operating satisfactorily. We have on this car a left and right-hand coupling to this spring; the threads on one side of this have given way. We have had to fix it up temporarily. We believe this was put on for experimental purposes, and is not a production feature. Spring Drive to Sch.628 - this appears from outside examination to be quite O.K. Mag. and Dyn. Drive to LeC.2019 and 2028 - the fabric couplings have slightly deteriorated, otherwise, the drive is O.K. Mag. has been dismantled, and we found the H.T. brush stuck right up in the holder, which has caused heavy sparking to the sector ring. Consequently, this has burnt rather badly. We also found the earthing brush broken. The magneto has been thoroughly cleaned, and these brushes replaced. Water pump white metal packing washer E.70631 - this is still satisfactory. Housing of water pump appears to be O.K. Battery ignition - since cleaning the condenser, connections and making this job O.K., the ignition points are in a very good condition. Please note, that the bone grey fibre rubbing block T.2. was O.K. when we replaced the contact points. This necessarily means that this is not now on the car. Cover E.73134 for oil filter (oil relay system) - quite O.K. Filter taken out for contd :- | ||