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).
Modifications to the Autovac fuel system to improve engine running.
| Identifier | WestWitteringFiles\N\July1925-September1925\ Scan67 | |
| Date | 14th August 1925 | |
| R.R. 493A (50 H) (D.D. 31, 12-6-25) J.H.L. EXPERIMENTAL REPORT. -2- Expl. No. REF Hs{Lord Ernest Hives - Chair}/AJL/L.G14.8.25. C Neither increasing nor decreasing the air space above the petrol level in the Autovac float chamber has any effect for the better or for the worse. We have introduced a reservoir in the form of a steam trap between the induction pipe and the Autovac in an attempt to cushion the gas and perhaps condense some of the vapour but no good came of it. We think that if it was possible to introduce pure air into the pipe in place of the highly carburetted air, the effect would not be so noticeable. If air is admitted into the induction pipe momentarily, the effect is a slight increase in engine speed, but without any of the 'lumpy' running or mis-firing associated with the present Autovac action. We have not been able to devise a means of accomplishing this up to the present, it is rather a problem to get rid of the carburetted air and substitute pure air for it. If it were possible to take exhaust gas into the Autovac instead of air, we think an improvement might be affected; the difficulty here however is that the exhaust gases would have to be at atmospheric pressure. The new suction elbow supplied to us by The Autovac Co. (report attached) is the only improvement we have so far been able to find. Hs{Lord Ernest Hives - Chair}/AJL. | ||