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).
Tappet rod tube corrosion in an aluminium cylinder head from chassis 97-KR and subsequent testing.
| Identifier | ExFiles\Box 47\2\ Scan144 | |
| Date | 27th September 1929 | |
| To Hn.{F. C. Honeyman - Retail orders} from Hs{Lord Ernest Hives - Chair}/AJL. c. to By.{R.W. Bailey - Chief Engineer} X4117 HS{Lord Ernest Hives - Chair}/AJL.2/MJ.27.9.29. CYLINDER HEAD OFF CHASSIS 97-KR. Corrosion of the tappet rod tubes occurred on the above aluminium cylinder head after it had been in service for less than 1,000 miles. It was thought that the cause of this was insufficient clearance between the tubes and the cylinder head wall, causing local steam traps and impeding the correct water circulation. The clearance was increased by machining out the head locally and the tubes were refitted. The head was then handed over to us for test and examination. It has since run 6,700 miles on 12-EX and has given no trouble; external examination of the head after this test shews no signs of failure. As this trouble is not general it appears that the clearance between the tubes and cylinder head wall is only just sufficient at the best, and should be increased to make sure no other failures can occur. HS{Lord Ernest Hives - Chair}/AJL. | ||