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).
Causes of petrol gauge failures and the subsequent modifications tested.
| Identifier | ExFiles\Box 61\3\ scan0051 | |
| 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. X4523 Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}1/MJ.24.6.30. X.4038. X.7530. X.7772. X.4523. X.7460. PETROL GAUGE. With reference to De/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.{Sir Henry Royce} R.{Sir Henry Royce} 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 | ||