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).
Letter to Messrs. Crerar, Morgan & Co. Ltd. regarding the unsuitability of their H.S. type sparking plugs for Bentley engines.
| Identifier | ExFiles\Box 58\2\ Scan305 | |
| Date | 4th March 1936 | |
| 862500. Expl. Dept. HS{Lord Ernest Hives - Chair}/Wst.3/MJ. 4th. March, 1936. Messrs. Crerar, Morgan & Co. Ltd., 172, Buckingham Palace Road, LONDON, S.W.1. Dear Sirs, Replying to your letter of the 3rd.inst., referring to your H.S. type Sparking Plugs. We have now received these plugs from Mr. Clark but unfortunately have not tested them because we do not consider they will stand up to the conditions met with on our Bentley engine using leaded fuels. We know this is the case, because you fit a copper electrode and copper electrodes practically disappear in a few hours running when leaded fuel is present. Will you therefore please let us know if you intend to modify these plugs, as we cannot undertake to test them in their present form. We would also point out to you that the reach of these plugs is very unsuitable for our Bentley engine as we require at least 12 mm. reach. Yours faithfully, For Rolls-Royce Ltd. | ||