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).
On an investigation into over-oiling issues in Cadillac overhead valve engines and the solutions they implemented.
Identifier | ExFiles\Box 174\2\ img111 | |
Date | 25th April 1937 | |
Snett a R.D. Latest file Sg.{Arthur F. Sidgreaves - MD} and Mr. [Crossed Out] C. Rm.{William Robotham - Chief Engineer}-----May [Crossed Out] De..-DMB..-Des. [Crossed Out] E.1/HP.25.4.37. Top Over-oiling of Overhead Valve Engines. I made a special point of enquiring about the above at Cadillacs, and found that they have been through exactly the same troubles as we experience. Over-oiling on the 12 cylinder Cadillacs came up very violently under city driving conditions, resulting in excessive oil consumption, fouled plugs and burnt valves. The difficulty was so pronounced in connection with a fleet of 12 cylinder Cadillacs taxicabs operating in New York that an arrangement was made whereby all the 12 cylinder chassis were bought back and replaced by 8 cylinder side valve cabs. On the other hand the same car that gave all this trouble in New York was quite satisfactory driven out in the West. The modifications adopted by Cadillacs to overcome the trouble are:- (1) Baffles to prevent oil splash on valve springs. (2) Improved drainage. (3) Mis-matched holes for feeding oil to the rocker tip. (4) A felt packing to seal the top valve spring washer. (5) Oil supply to rockers arranged with a relief hole so that oil pressure cannot build up with speed. With regard to item No.(3) they prefer the mis-matched holes to metering oil through felt pellets, such as we have adopted. They say they tried the latter scheme but found that it tended to become silted up. With regard to the felt seal mentioned in item | ||