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).
Solution to a mysterious water loss from the cooling system and a note on oil loss from shock dampers.
| Identifier | ExFiles\Box 1\4\ B001_X 100a-page034 | |
| Date | 13th November 1932 | |
| To ns.{Norman Scott} From G.W.H. hotel de france, Chateauroux, FRANCE. 13.11.32. 2.PER.II. we have solved the mysterious loss of water from the water system. Apparently it is not the pump that is too efficient, but we have got to verify that point. The trouble is caused by the position of the overflow pipe outlet. This comes almost to the bottom of the radiator. There is a space between the bottom of the radiator and the front underpan. The underpan being fastened to the crossmember. The shape of the underpan is such that when the car is travelling at speed it causes a depression to be formed in the space at the bottom of the radiator. This depression actually causes a depression in the top tank of the radiator sufficient to hold the water momentarily, the pump then delivers a certain amount filling the top tank causing it to overflow. The depression then in the top tank is greater than that caused by the suction and air enters. This goes on until a gallon of water is lost. we have definitely cured it by two methods. Firstly, we plugged up the overflow pipe, then fitted a radiator cap with a hole in the top open to atmosphere. We fully expected water to be thrown out, but instead no water came out and none was lost. Secondly, The pipe we had soldered on to the radiator cap approx. 3" high was taken off leaving just a hole in the cap. The result was just as good, no water was lost. Thirdly, We replaced the overflow pipe with a scoop at the bottom facing the wind. Standard radiator cap fitted without the valve. Result. - No water lost. We are pleased we have got this result as we have tried all ways to make the waterflow, but were not successful, and we had grave doubts of steam pockets in the cylinder head. SHOCK DAMPERS. The loss of oil from the glands is not consistent. The front dampers are giving no trouble. The cause is weakness in the design of the gland cap bolted on to the case by two studs and nuts. | ||