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).
Technical report on issues with pistons, carburettors, and the exhaust system.
| Identifier | ExFiles\Box 83\4\ scan0224 | |
| Date | 27th May 1936 guessed | |
| ( 2 ) PISTONS Aerolite Pistons. Identification 04 RM.{William Robotham - Chief Engineer}81 Slotted Scraper Rings. There has been slight piston knocks upon first starting up from cold. There was no sign of a seizure or cracks when examined. CARBURETTERS. LOP EB.2705. We had considerable trouble with the carburetters flooding while slow running (i.e. engine idling). This caused a rich mixture which stopped the engine. The changing of needle & seating made no difference. One float appeared to be causing the trouble. No real satisfactory cause could be located. One thing was noted, that was, the float was heavy on one side and did not float true. This appeared to cause an uneven pressure on the float mechanism which would not shut the needle off. We eventually changed the floats from one carburetter to the other and the flooding ceased. While trying to cure this trouble, we noted that the petrol pump pulsated every 5 secs. which aggravated the trouble. The petrol pump pulsations overcame the floats & caused flooding. This was traced to leaky valves in the pump. CARBURETTER AIR SILENCER. LOP EB.2788 LEC 4818. The air silencer is satisfactory in silencing the carburetter roar. The anchorage has remained firm. The corrugated end for the air intake has become loose in the barrel of silencer. EXHAUST SYSTEM. LOP EB.2828. At 2,600 the tail pipe anchorage became loose and rattled. This anchorage wears quickly, the holes in the steel pressings for anchorage bolts become elongated. At 4,500 miles, a bad exhaust blow developed from the front expansion box where the down exhaust pipe enters. The metal had cracked all round the joint. This was temporary welded up. With the aluminising of the metal, welding cannot be accomplished until all the aluminium has been filed off. An improved front silencer & down pipe was fitted, which has not given any trouble. The manifold which was aluminised, very quickly became a mass of blobs, the aluminium melting and running. It was finally burnt off. A new manifold black enamelled warranted not to burn off was fitted. After two days running there was a fine series of cracks all over the manifold. In less than a week's running, practically all the enamel had vanished, burnt and peeled off, in very fine pieces. The manifold joints have not given any trouble. The intermediate pipe from first silencer to rear silencer, is, on this car too close to the centre chassis cross member, and the spring Handwritten text: (Top left margin) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} RADCLIFFE Any trouble experienced on test? No NEEDLE POSITION VARIES. (Middle left margin) Wyman: why? m/c by outside white (Bottom left margin) ? Noted G.S. | ||