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).
Autovac failures on the Phantom model, including flap valve issues and petrol line gassing.
| Identifier | ExFiles\Box 40\4\ Scan289 | |
| Date | 19th November 1928 | |
| To Br.{T. E. Bellringer - Repair Manager} from Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} c. to Hn{F. C. Honeyman - Retail orders}; g.{Mr Griffiths - Chief Accountant / Mr Gnapp} to Mx.{John H Maddocks - Chief Proving Officer} AUTOVAC FAILURES ON PHANTOM. With reference to Br1/S14.11.28. Our experience is that on certain Autovacs, for some obscure reason, the flap valve occasionally fails to close. There does not seem to be any inconsistency about the behaviour of this valve and the trouble is therefore all the more difficult to trace. We have only encountered the trouble once or twice in all the Autovacs we have had in our hands. We recommend that if an Autovac gives trouble consistently, it should be changed and the offending instrument sent to us for investigation. Another trouble which may easily be mistaken for an Autovac failure is gassing in the petrol line. We have come across this trouble since fitting petrol filters with metal bowls. It will only occur if a very volatile petrol is used, and usually with a non-ventilated bonnet in hot weather. This trouble can easily be distinguished from the autovac trouble because if when the car dries up, the autovac is turned off and the float chamber cover removed, when the autovac is turned on after the car has been standing a few moments, the float chamber will fill with petrol if the stoppage has only been caused through gassing in the pipe line. We have a modification in hand which consists of ventilating the filter and which entirely overcomes the troubl of gassing in the pipe line ---- | ||