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).
Cylinder re-grinds and the mileage at which they are typically required for different car models.
| Identifier | ExFiles\Box 107\2\ scan0101 | |
| Date | 3rd June 1938 | |
| BY.{R.W. Bailey - Chief Engineer} Rm{William Robotham - Chief Engineer}/GRH. -------- Hd{Mr Hayward/Mr Huddy}6/IB.3.6.38. ------------ CYLINDER RE-GRINDS. ----------------- In reply to your BY.20/G.2.6.38., we have checked over ninety-one cases of cylinder re-grinds, and these have all been due to normal wear and tear, which in effect amounts to increased oil consumption. We seldom have to re-grind for piston slap, and over-oiling of plugs is generally due to cylinder wear and mileage. Our experience is that customer's require a re-grind on:- 1. Bentley at 30,000 miles. 2. 20/25 HP. " 35,000 " 3. P.II. " 40,000 " Hd.{Mr Hayward/Mr Huddy} | ||