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).
The causes of petrol gauge failures and the subsequent modifications made to resolve them.
| Identifier | ExFiles\Box 15\7\ Scan154 | |
| Date | 24th June 1930 | |
| To R.{Sir Henry Royce} From Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to EV.{Ivan Evernden - coachwork} c. to Cy. c. to C. X 7530 Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}1/EJ.24.6.30. X.4038. X.7530. X.7772. X.4523. X.7460. PETROL GAUGE. With reference to Da{Bernard Day - Chassis Design}/Ev.{Ivan Evernden - coachwork}1/M16.6.30. A short time ago we went into the statistics of gauge failure, a record of which Major Searight Managing Director of Messrs. Claudel Hobson's has, and it was found that 99% were due to the following causes :- (1) The K.S. liquid getting into the capillary tube at the head of the gauge, due to the way the gauge head was handled before being fitted. (2) A leak in the top or bottom of the glass tube due to the fact that the gauge is coupled up and un-coupled more than once on R.R. cars, and in consequence these joints have to put up with more than this on a car where the body and chassis are not made in separate factories. (3) Petrol in the air line due to the gauge being in-correctly coupled up at some time before the delivery of the car. --- After having carefully considered these sources of trouble, the following modifications have been made to the gauge, and were run on the last 10,000 miles test. (1) A chamber of appreciable capacity was left at the top of the glass tube in order to prevent liquid | ||