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).
Query regarding issues with the self-adjusting tappet mechanism on a Phantom III chassis, including misfiring and valve problems.
| Identifier | ExFiles\Box 146\3\ scan0196 | |
| Date | 2nd December 1936 | |
| Pedes 1245 To Rolls-Royce Ltd. Derby ........ Rm.{William Robotham - Chief Engineer} Copy to ...... Hd.{Mr Hayward/Mr Huddy} Mr Levallois Sr/VA4/ET.2.12.36 Re: SELF ADJUSTING TAPPET MECHANISM ON PHANTOM III CHASSIS Will you please let us know as soon as possible the clearance on diameter between the plungers and the bores in the casings. Has any alteration been carried out of late to the above or has more working clearance been given to the plungers. Have you experienced any trouble due to the plungers holding the valves off their seats and thereby causing misfiring and irregular running at slow engine speeds.? We have experienced starting up trouble on chassis 3.AZ.20, our Trials car, and since the changing of the engine oil from Castrol XL to Mobiloil arctic as recommended in Depot Sheet N° Hd.{Mr Hayward/Mr Huddy}317, this trouble has disappeared. Another trouble, however, has developed, which we are now investigating and that is that, after the engine been run a short distance, the plungers appear to be holding several of the valves off their seats, causing the engine to misfire. As soon as we have definitely located the trouble, we will drop you a line. Sr/VA.VA. M.{Mr Moon / Mr Moore} Sewell. Please supply the clearance information, also a sketch to show the trouble due to works driving the pin into the side of the eccentric. Rm.{William Robotham - Chief Engineer} | ||