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).
Letter to Autovac Manufacturing Co. Ltd. regarding a faulty autovac tank unit from an experimental car.
| Identifier | ExFiles\Box 40\4\ Scan355 | |
| Date | 17th December 1931 | |
| X3579 Hs{Lord Ernest Hives - Chair}/Lid.{A. J. Lidsey}4/KT. Dec.17th, 1931. Autovac Manufacturing Co. Ltd., Heaton Norris, Stockport. Dear Sirs, We are posting to you today, under separate cover, an autovac tank unit taken off one of our experimental cars. The autovac until recently, has given good trouble free service, but now it has developed the trouble of sticking occasionally and not delivering any petrol. From observations we have made it appears that the float reaches the bottom of its stroke, touching the float chamber bottom, before the spring toggles the valve mechanism over to close the air valve and open the suction valve. When sticking occurs the autovac can be made to function again by knocking the tank; the trouble only occurs when the car is stationary, road vibrations are apparently sufficient to free the mechanism when sticking occurs. We suggest that you would like to try out the unit in your glass autovac tank, whn possibly the cause of the trouble could be seen. We have tried the unit in several different tanks, not changing over the float chambers and have found that the trouble follows the float mechanism. The float also appears free from leaks. We shall be very interested to hear that you can find an explanation for this phenomenon. Yours faithfully, FOR ROLLS ROYCE LTD. | ||