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 5,447 miles, detailing engine issues and component checks.
| Identifier | ExFiles\Box 71\4\ scan0135 | |
| Date | 16th April 1925 | |
| 48840 Hotel de France, Chateauroux. Indre. France. GWH.{George W. Hancock - Head Chateauroux}I/Crn. 16.4.25. TO: "HS{Lord Ernest Hives - Chair}" From: G.W.Hancock. -- -- -- -- -- -- -- -- -- -- We wired you this morning, as follows :- NUMBER TWO CONROD BIG END BEARINGS GONE - HANCOCK. and thank you for your wire, reading :- MARSTON LEAVING TODAY WITH NEW COUPLINGS AND OTHER PIECES - HIVES. Report on chassis 93 NK after 5,447 miles. ENGINE. The engine had run particularly smooth up to the big-end going on No.2 con rod. all the white metal has run out of this end. we have no explanation to give but that some foreign matter had passed through the filter. This we know can happen, as very fine pieces of the white metal had passed through to the filter of the oil relay, where it had been held up by the filter there. we had been doing some high speed running, but the car had slowed down on a corner when the bearing went. this was nine miles from the garage. The journal on crankshaft does not appear to be damaged. there are the marks of the grooves of bearing caps, but these are white metal marks. The oil filter was fairly clean. We have taken cylinder head off - nos. 1, 2 & 3 pistons shewed considerable over-oiling. nos. 4, 5 & 6 pistons were well oiled. There was a thick deposit of carbon on pistons, also outer ridge of cylinder. Valves also had a heavy deposit of carbon. Exhaust valve heads have distorted slightly, bedding being approximately half way round seat. These have all been ground in and are now O.K. Inlet valves were very good. guides of all valves are good - no undue wear appears to have taken place. Magneto & dynamo drive O.K. Water pump housing & packing O.K. Exhaust boxes have retained their positions since last fitting up, when more clearance was given to dowel pins. Cast iron choke valve on down take pipe seizes slightly occasionally, but becomes free on its own. At no time has it remained open when car has returned to garage. Carburettor - butterfly throttle has given no trouble. Car has been particularly good for absence of exhaust explosions on over run. Filter - very small amount of dirt & fluff. Air valve diaphragm - the diaphragm has now movement of .0312" up & down, due to the whole becoming elongated where pin goes through dash pot. Oil relay - leather washer has got hard, and top half broken away - new washer required. It still functions, but is sluggish. Filter in same had fair amount of fluff deposit, also small particles of white metal. front engine suspension O.K. | ||