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).
Tests and modifications for 4 Port cylinder heads, valves, and associated fittings.
| Identifier | ExFiles\Box 92\3\ scan0271 | |
| Date | 31th May 1937 guessed | |
| ( 4 ) Cylinder Heads. 4 Port. LOP. E.88261 Lec.4729-40-63. Complete to the above LOP and Schemes:- Ex. Ph.III. N° 13 unit. E.87735 Cylinder Heads. Harrison car heater taps on engine. New parts fitted to suit Harrison car heater taps on engine. 2 steel gaskets per head removed at 11.210 miles and replaced by Copper and Asbestos. The cylinder heads were removed after 9,000 miles running for the purpose of changing the exhaust valves. There was a fair carbon deposit which was removed. The inserts were in good condition. The heads were again removed at 11.210 miles but the carbon deposit was not removed as it was not excessive. With the copper and asbestos gaskets, water leaks occurred up most of the outside holding down studs, which were cured by wrapping packing material under the nuts and washers. Leaks were experienced from the taps for the Harrison car heater. [Handwritten note] Swell - What are we standardising on the 4 port head. Valves & Fittings. LOP. E.86922 Lec.4903-5341. Complete to above LOP incorporating following new parts:- "A" side head E.88448 Exh.Valves - S/SLV. not stellited. "B" side head E.88447 Exh.Valves - KE.965. stellited. All Exhaust Valves removed at 9000 miles and replaced by 12 new exhaust valves in KE.965 stellited. E.88165 Inlet Valves S/SLV. Diametric clearance in the guides of .0015 - .002 Low carbon valve springs supplied by Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} Fescolised tappets. Standard production. E.88500 bottom tappet springs - produced in S/CV. Oil supply holes plugged up on plunger casing. Plugs removed after 1000 miles running to reduce flow from rocker bushes. 24-Ex.25247 Distance pieces, in conjunction with non-silent tappets. 24-Ex.25504 Adjusting screws. .015" dia.hole drilled in the valve end of each rocker. .015" hole in bronze floating bushes. 4 pellets in felt in each rocker as specified by Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} N° 6 valve on "A" side, exhaust S/SLV, stuck open after 9,000 miles running. Tappet adjustments indicated stretch (contd) | ||