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 an engine failure on chassis GAU-48 due to a sheared split pin, discussing material upgrades and a replacement engine.
| Identifier | ExFiles\Box 130\1\ scan0006 | |
| Date | 2nd February 1933 | |
| To Wor.{Arthur Wormald - General Works Manager}from Hd.{Mr Hayward/Mr Huddy} Hd{Mr Hayward/Mr Huddy}2/MW2.2.33. 20/25 HP. Chassis No.GAU-48 - Park Ward Trials Car. ------------------------------------------- The above car which has been used by Cr.{Mr Cra???ster / Mr Chichester} has now had the engine unit completely dismantled for inspection to find out the cause of the damage to the crankcase etc. After very careful investigation there is no doubt that the 1/16th split pin in No.3 Conn. Rod big end bolt has sheared, causing the nut to become loose from the bolt and the big end conn. rod bearing cap to become detached and so cause all the damage to the cylinders, crankcase, conn, rod and piston. Since this engine was built this particular type of split pin has been superseded by a stronger type made of Staybrite steel. In view of the increased performance on the Synchro-mesh type chassis, and the fact that one can accelerate to 60 m.p.h. so easily on third gear, and the engine revs. are approximately in the vicinity of 3000 per minute, I suggest for your consideration that the views of the Design Dept. and Experimental Dept. are obtained as regards this failure, to ascertain whether any action should be taken to the engines in service. The various types fitted to engines are as follows :- 1/16th Split Pin easy fitting type 142 Chassis 1/16th Split Pin mild steel, better fitting type 94 " The remainder of the engines have been fitted with 1/16th Split Pin Staybrite steel, latest type. The new engine unit is now being assembled in the chassis and we shall have the car on test tomorrow, Friday. The new engine No. is L.3.B. and as the change of engine numbers affects the Registration of the car, it will be necessary for the party in whose name the car is registered to be advised of the new engine number, in order that the party in turn can advise the Licencing Authority concerned. Hd.{Mr Hayward/Mr Huddy} | ||