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).
Faults found during tests with the 98-NK car in France.
| Identifier | ExFiles\Box 71\4\ scan0054 | |
| Date | 25th September 1924 | |
| R.R. 493A (50H) (D.B. 175 25-9-24) J.H.D. EXPERIMENTAL REPORT. Expl. No. X8940 REF. HS{Lord Ernest Hives - Chair}5/LG11.3.25. To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. BJ. c. to RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to DA.{Bernard Day - Chassis Design} BY.{R.W. Bailey - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} S E C R E T. TESTS WITH 98-NK CAR IN FRANCE. X8940 98-NK car ran 5,200 miles in France before the piston failed. During that time the following faults were reported :- (1) The front engine mounting allowed engine to drop. The engine mounting on 98-NK car was returned with the broken piston. It was found that the bearer tubes had bent close up to the bracket brazed at the front end. The tubes were bent sufficient to allow the engine to drop .200". We have been instructed for drop forged bearer arms. For experimental cars we are making these from hand forgings so as to avoid delay in making dies. (2) Excessive oil consumption. When the car was running 500 miles per day, the average oil consumption was 250/260 m.p.g. When the amount of oil to the rockers was reduced it was 280/290 m.p.g. This figure is very much too high. The standard 40/50 HP. running under similar conditions, average 1100/1500 m.p.g. We have been carrying out tests on the bench in connection with this and have proved that we can improve the oil consumption by modifications to existing rings and pistons. This matter is being dealt with in a separate report. (3) Loss of water. There was a complaint of loss of water. On an contd :- | ||