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).
Ignition issues for the Goshawk engine, with suggestions for modifications to the distributor cover and LT rocker spring.
| Identifier | ExFiles\Box 54\5\ Scan194 | |
| Date | 2nd June 1922 | |
| To By. {R.W. Bailey - Chief Engineer} from R. {Sir Henry Royce} c. to Wor. {Arthur Wormald - General Works Manager} Hs. {Lord Ernest Hives - Chair} EFC. {E. Fowler Clarke - Electrical Engineer} c. to Da. {Bernard Day - Chassis Design} EP. {G. Eric Platford - Chief Quality Engineer} Hy. {Tom Haldenby - Plant Engineer} E. {Mr Elliott - Chief Engineer} 13485 R5/M2.6.22. X.4357. GOSHAWK - IGNITION. X.3485. With reference to the ignition on No.4 Goshawk, I found the distributor cover very tight to get off. I ground a square file into a scraper at the end, which was very nice to scrape this part. It should be made with a definite clearance of I should think 5/1000. On examining the facility for changing the L.T. rocker and contact maker I found it slightly difficult. This could be definitely improved as follows :- The hole in the spring might be made into a slot and the screw fastening the spring could be pointed to a long cone of 60° or slower. A break of about .010 to .012 appeared to be about right for an even make and break. This may be still less if the fibre bakelite rubbing pad is worn. This should be ascertained. (cam may need modifying). The spring of the rocker is I understand made of steel but its rating is too great because it is made too thick. The pressure on the points when in contact seems about right but to lift it and handle it the spring is much too rigid and very likely to be of the wrong pressure, either insufficient or excessive, both of which would be bad. Please send me a new rocker with a better spring and the improvement for facility of fitting. The contacts were found to be in good order. You will remember th with this engine and ignition, I found no fault with either K.L.G. or Lodge plugs of the type Contd. | ||