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 discussing the operation of the Autovac fuel system, float, and suction valve mechanisms.
| Identifier | ExFiles\Box 40\4\ Scan150 | |
| Date | 30th November 1925 guessed | |
| -2- thus more petrol will be passed through the tank than in case No.1. in which the amount of petrol passed depended only upon the working stroke of the float; the same reading will be registered by the Galometer in each case although more petrol has passed in the second case than in the first. Of course, it may be stated that as soon as the float falls, the suction valve will be opened and the flow of petrol will be arrested, but this action cannot be instantaneous owing to the time required to exhaust the Autovac, especially so in case No.11. where the suction will be small, and it is quite possible that during this period of time all the petrol will fall from the float chamber, if not all, at any rate more than in case No.1. will fall. This condition will of course also occur when the reservoir is empty and the Autovac is filling it up to its correct level. We should be pleased if you could let us know whether this assumption is correct - there may be some action of the valve mechanism which prevents it occurring - it is rather difficult to follow the toggle mechanism on the drawing supplied, in any case it would be interesting to receive your views on the matter. Thanking you in anticipation. Yours faithfully, | ||