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).
Carburation practices for both aero and car engines, covering suction, cold starts, and heating.
| Identifier | ExFiles\Box 13\3\ 03-page062 | |
| Date | 1st January 1929 | |
| HS.{Lord Ernest Hives - Chair} E.{Mr Elliott - Chief Engineer} RG.{Mr Rowledge} From R.{Sir Henry Royce} c. to BJ. Wor.{Arthur Wormald - General Works Manager} c. to SG.{Arthur F. Sidgreaves - MD} BY.{R.W. Bailey - Chief Engineer} F.{Mr Friese} 47080 R1/M6.1.29. CARBURATION - AERO & CAR. X.3933 X.7080 X.4434 (1) It is possible that to give satisfactory results we must have fairly vigorous suction upon the carb. This <s>may-have-departed</s> has always been our car practice. We may have departed too far from it in our aero engine practice, hence my suggestion of smaller throats, and sacrificing some power, even if we have to run the supercharger somewhat faster to get the desired induction pipe boost. (2) Probably it is necessary to have an extra supply of petrol to make the mixture over rich for starting cold - i.e. nearly twice the proportion advisable for idling warm. To do this we might have extra starting carb. as well as correct slow speed slot at throttle edge. Here again we should be following our car practice, which we have found so much better and safer than flooding or strangling. (3) Apparently we must in all aero engine work, including the R.{Sir Henry Royce} engine, provide sufficient heat to the carb. It would be easy to turn off if we suffered from over-hot carbs. I realise that we had done something and are doing more, but I am now saying overdo it in all cases as thoroughly and as quickly if we know now. I believe all our earlier engines drew the air for the carbs. from under the cowling. When the mounting would not allow this freezing and other carburation troubles shewed themselves. We have often suggested taking the air through the crankchamber, or part of it, so cooling the oil and warming the air. Some such practice may be found necessary. R.{Sir Henry Royce} | ||