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).
Vauxhall's thermostat testing methods and cooling system performance.
| Identifier | ExFiles\Box 156\1\ scan0258 | |
| Date | 17th September 1937 | |
| 2. (4) Messrs. Vauxhall's method of testing thermostats is to take a percentage each month from a batch of deliveries and check them (a) opening and full open temperature. (b) for resistance to fatigue by means of a simple rig which alternately immerses them in cold water and hot water ( 190 - 210°F ) 360 temp. changes per hour being made. Any type thermostat which can withstand this test satisfactorily for 70 hours, is found to be entirely satisfactory in service. Messrs. Vauxhall stress the fact that the standard of reliability which they wish to attain is typified by the similar thermostat unit made by the Harrison Radiator Corporation of Stockport, N.Y. (Note - The thermostat unit which we shall use, purchased from the British Thermostat Co. costs 6/- in lots of 200. The Harrison thermostat can be bought for 34c in lots of 1,000.) The latter test is more in the nature of an experimental development test than a production routine test. (5) The temperature control on the road with these units is very good - maximum variation approx. 6°F.{Mr Friese} (6) They have had to specify anti-freeze to be used in cold weather with their system. We shall have to do the same with ours. In addition to the information given on thermostats we learnt also:- (a) That the maximum water circulation on the 25.H.P. Vauxhall car is roughly the same as on our Bentley or 25/30 cars. i.e. 20 galls/min. (b) That the H.P. absorbed by their 25 H.P. car fan is in the region of 3.B.H.P. (c) That their method of testing for adequate cooling on their cars and trucks, is to run them full throttle (1) In bottom gear at 5 M.P.H. (2) In 2nd gear at 10 M.P.H. (3) in 3rd. gear at 15 M.P.H. (4) in Top gear at 20 M.P.H. and measure critical air temperatures under these conditions minimum satisfactory critical air temp. under these conditions being approx. 38°c. | ||