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).
Troubleshooting guide listing engine running problems and their probable causes.
| Identifier | ExFiles\Box 178\1\ img072 | |
| Date | 26th November 1925 | |
| - 11 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs{Lord Ernest Hives - Chair}/ACL/LG261125. TROUBLE. PROBABLE CAUSE. Richness at low speeds light loads. 1: Jet set before air valve starts to lift. 2: Diaphragm set too low down in high speed choke. 3: Spring pressing tightly on air valve when in down position. 4: Leakage passed dash-pot cover. 5: Leak holes too small. Richness at position where air ports open. 1: Spring pressing too tightly on air valve. 2: Low speed jet too rich. 3: Leakage past dash-pot cover. Weak at high speeds. 1: Obstruction in jet or filter. 2: Collar on needle valve moved from its correct position which prevents needle lifting to its full extent and thereby restricting petrol flow. Poor acceleration with no popping back. 1: Air valve not lifting quickly enough due to insufficient leak holes. Popping back on acceleration. 1: Cold hot-spot. 2: Obstruction in jet or filter. 3: Very rapid lift of air valve due to wear. High speed jet weak at high speeds and unable to make sufficiently rich. 1: Spring not lifting jet needle or operating toggle not permitting jet to lift to full extent. 2: Filter stopped. | ||