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).
Investigation into overheating complaints on the Phantom III model, identifying the cause as radiator matrix silting.
| Identifier | ExFiles\Box 94\3\ scan0206 | |
| Date | 7th June 1937 | |
| To Sg.{Arthur F. Sidgreaves - MD} from Rm{William Robotham - Chief Engineer}/Std. Hs.{Lord Ernest Hives - Chair} c. to E.{Mr Elliott - Chief Engineer} c. to By.{R.W. Bailey - Chief Engineer} c. to Mx.{John H Maddocks - Chief Proving Officer} c. to Hd.{Mr Hayward/Mr Huddy} c. to Br.{T. E. Bellringer - Repair Manager} c. to H.{Arthur M. Hanbury - Head Complaints} & C. 340 OVERHEATING COMPLAINTS - PH.III. We have investigated complaints of the above nature which have so far been received and find that overheating is experienced under two different sets of conditions:- (1) when running in dense traffic and idling for long periods. (2) when driving full throttle at high speeds. The first type of overheating has resulted in a complaint from the owner that his thermometer indicates over 100°C - in general he does not lose water under these conditions - the only cases where water loss has been experienced are due to incorrectly set steam valves. The second type of overheating causes both high temperatures on the thermometer and if the car is driven hard, water loss occurs. The second type of overheating is due to silting up of some of the waterways of the matrix and has been so far confined entirely to the Mk.V. type of matrix which was fitted to the first 171 Ph.III. chassis. The silting up is due to (a) corrosion product of aluminium and iron (mainly aluminium hydroxide) forming in the water system. (b) The corrosion product so formed choking the matrix waterways which are insufficiently large at their ends owing to defective inspection after construction. Some of the defective matrices have been returned to Messrs John Marston (the makers) for examination and a copy of their report is attached. All Ph.III. Mk.VI. matrices have had their waterways opened correctly by our Radiator Shop. No overheating of this nature has been experienced on experimental 15,000 miles cars. Messrs John Marstons are of the opinion that they can renovate silted up matrices by removing the tanks, cleaning out the matrix with an agent known as 'Kyrac' - opening up the waterways and refitting tanks - further, they have undertaken to carry out this operation free of charge if we return defective matrix units to them. continued | ||