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).
Tests and modifications to prevent engine oil loss and manage oil levels in the sump during a road test.
| Identifier | ExFiles\Box 1\4\ B001_X 100a-page200 | |
| Date | 6th February 1933 | |
| To Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} From GWH.{George W. Hancock - Head Chateauroux} E PLEASE RETURN X4057 JN Hotel de France, CHATEAUROUX, Indre. France. 6.2.33 Seen. will E indicate alterations we are to make 3 PER. 11. By - E designer mod. B.H. & Case B/SS{S. Smith} We have received your memo HS{Lord Ernest Hives - Chair}-RM{William Robotham - Chief Engineer} 8/KT 4.2.33. We have not as yet been able to carry out any oil temp. tests as we have been too busy trying to prevent loss of oil from front of engine. The reason for this is that on the run from Derby to here it was found necessary to put 2 qrts of oil in at Folkestone, and 1 qrts at Rouen, with very erratic oil pressures during the journey. We noticed that the gauge in the sump, when travelling at speeds, showed practically empty. We have therefore been trying to prevent the oil being lost from the front of the engine, also to keep the supply in the rear compartment. The result of the modifications to the bottom half we have reported to you. We are now considerable better off in the loss of oil from the front of the engine than what we were, but it still is not altogether cured. We are however, maintaining the oil more level in the bottom chamber; at 60 mph. the gauge reads 3/4 of the amount of oil in the engine. We are satisfied with regard to that condition. To obtain this result we have made the weirs to a height of 2 1/8" from the top face of the base chamber; that is the weirs have been increased in height approximately 1 1/4 inches. The by-pass holes in the weirs remain as stated in our last report. We further carried out an interesting test to watch the effect of the oil in the base chamber by first heating up the bottom half to approximately 80°, then placing 1 1/4 gallons of oil at 90° in the engine base, put base facing forward in the back of 19 EX, and then took it on the road. Upon acceleration there is a slight building up of the oil in the rear compartment. Running at a steady mileage the oil was perfectly level in each compartment. Taking a normal brake effect at 50mph. the oil surged up to the top of each weir, but did not overflow. The quantity of oil in each compartment kept approximately the same amount. The test was repeated with severe braking, and although a small quantity of oil surged over the tops of the weirs, the quantity was not sufficient to make it overflow over the front aperture. Upon acceleration after braking the oil became level in each compartment within five seconds. We were quite happy and satisfied with these results. The remaining problem was that of the release oil from the release valve unit is released into the front compartment by a hole in the camshaft housing; the quantity of the release oil is tremendous, therefore to lessen the volume of release oil being emptied into the front compartment we fitted a pipe with a 5/16 bore to take part of the release oil and feed it into the rear | ||