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).
Request for the production of specific tappet guides and top spring washers for the Wraith III model.
| Identifier | ExFiles\Box 10\3\ 03-page039 | |
| Date | 25th June 1937 | |
| To HPS.{Horace Percy Smith - Experimental Factory Mgr} from Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}1/AP.25.6.37 WRAITH III. As requested verbally will you please produce for us 6 tappet guides in I/C. otherwise to EW.859. It will be necessary to shrink these into the case when the latter is raised to a temperature of 50°C. In order to obtain the same fit as at present with alum. guides, the external dia. of the cast iron guides to be .0015" bigger than the dimension shewn on EW.859. The above to be produced with the bore offset at 45° as carried out on Wraith No.1. The object of the above is to keep the clearance between the bottom tappets and guides a minimum, to complete the job therefore will you ensure that the tappets in these particular guides do not exceed a diametrical clearance of .001" on assembly. If possible we would like these fitting in Wraith No.3. unit. Remaining 6 tappets and guides as No.1. unit. As we have no bottom tappet springs we are having trouble to overcome valve bounce and are having to do everything at present at the valve spring end. In connection with the above will you please produce 24 top spring washers to Rm.{William Robotham - Chief Engineer}400. These are urgent. Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} | ||