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).
Test report on modifying and observing oil pressure, delivery, and jet performance using different oil types and temperatures.
| Identifier | ExFiles\Box 103\4\ scan0057 | |
| Date | 29th May 1929 guessed | |
| -2- The pressure was increased to 25 lbs/sq.in. - the standard main oil pressure with slightly better results but still No.1 jet was too slow. The supply pipe was then connected to the centre of the delivery pipe in order to obtain better pressure distribution with marked improvement. Jets .032, .046 and .062" diameter were tested, it being finally decided to adopt the latter dimension, this giving a short oil stream at the two centre jets, slightly less at Nos. 2 & 5, and a shade less at Nos.1 & 6, [text obscured by strikethrough] also being large enough to avoid obstruction. Nos.1, 2, 5 & 6 jets were prevented from "streaming" by capillary action, and it was decided to redesign them for use on the car with taper instead of straight nozzles to overcome this as much as possible. A Zenith petrol filter added to the circuit at this stage performed quite well. The pressure previously recorded were taken from the pump or inlet side of the delay valve. With the pump pressure set at 25 lbs/sq.in. it was found that the pressure at the beginning of the delivery pipe was only 6 lbs/sq.in. and with the filter removed 7 lbs/sq.in. To obtain 10 lbs/sq.in. delivery pressure a pump pressure of 30lbs/sq.in. was required. In all the above tests Amber A.{Mr Adams} oil was used, in order to produce the conditions obtained with standard engine oil - Price's Motorine C. - at 0°C. Tests were then taken with Motorine C. at normal temperature, both for feed oil and damping oil. The delay period was reduced to approx. 3 mins. jets 3 and 4 gave a 1" stream, 2 & 5 just falling clear of the nozzles, and 1 and 6 flowing down the nozzles. At 50°C the oil streamed well from all the jets the stream varying from 2-3 inches in length. The delivery pressure at this temperature was 4 lbs/sq.in. for a pump pressure of 35 lbs/sq.in. At 3½ lbs/sq.in. pump pressure the delivery was not quite sufficient to clear the nozzles. W.Bell. | ||