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).
Issues with single-line petrol gauges and comparing them to other alternatives.
| Identifier | WestWitteringFiles\W\May1931-August1931\ Scan106 | |
| Date | 24th August 1931 | |
| ORIGINAL. To R.{Sir Henry Royce} From Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}3/MJ.24.8.31. c. to Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. to E.{Mr Elliott - Chief Engineer} Da.{Bernard Day - Chassis Design} c. to By.{R.W. Bailey - Chief Engineer} PETROL GAUGES. 84038 K4523. We have now had the single line petrol gauge on test for some months. A feature we have noticed on this gauge is that if the car is run about on short journeys and after each run the tank is topped up, in time the gauge ceases to function. This is because until the level of the petrol tank has fallen to about 16 galls. no pumping action takes place and in consequence the air in the tank bell is gradually replaced by petrol. This is especially noticeable in hot weather. The single line petrol gauge is no worse than the standard double line unit in this respect, but the fault has never become manifest on the present gauge because a hand pump is provided which enables the driver to replace the air in the tank unit at will. Therefore, the only thing necessary to bring the single line petrol gauge into line with the double line petrol gauge is to fit a hand pump. The other disagreeable feature of the centrally vented gauge in the tank is that when the tank is filled full and the car is driven under certain conditions, petrol is spilt in appreciable quantities and might give rise to complaints of fumes in the ears of some of our more particular customers. One method of overcoming this is to collect the petrol so spilt, and convey it to the side of the car by a pipe. We have rigged this up experimentally. Whilst this may overcome the difficulty, the whole petrol gauge becomes so cumbersome that it can hardly be considered a practical proposition, more especially as the tank has to be designed more or less around it already. The alternative hydraulic gauge is the "Nivex" of which you have already had particulars, and which we ran for 10,000 miles in France. The one advantage that this has over the Hobson gauge, is that since it can stand the overload it does not require a balanced pipe line nor does it require the tank to be specially vented to enable it to function. In every other respect it is similar to the K.B. gauge with the added disadvantage that it has moving parts to wear out. One other distance petrol gauge which is widely used is the electrical type. We ourselves have come up against some singularly bad examples of this type, but apparently it has recently been made more reliable, and we are arranging to try one on one of our experimental cars. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||