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).
Instructions for diagnosing spark plug faults using a tester based on the resulting light glow.
| Identifier | WestWitteringFiles\I\October1922\ Scan76 | |
| Date | 6th November 1918 | |
| RR 238 (300 Bks.) (SF 152. 6. 11. 18.) MP 197880 ROLLS-ROYCE LIMITED. INSTRUCTIONS. To Order No Customer's No. 3 19 is conveyed back through the condenser to the HT point under test whilst all the other sparks are discharging. The effect then is a continuous glow of mild intensity with an intermittent bright flash every time the spark passes at the test gap. With a little familiarity therefore, the tester should enable properly working plugs to be discriminated from faulty ones, though it will not indicate the nature of any faults that may exist. Too bright a light indicates too wide a gap as the makers say, but too wide a gap will make a dim light if it causes misfiring. Signed F J Allen This Sheet must be filed on completion of the work. | ||