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).
Comparison of crankcase oil dilution using different oils, fuels, and choker systems on Springfield chassis.
| Identifier | ExFiles\Box 50\3\ Scan132 | |
| Date | 9th July 1921 guessed | |
| Cy2 - G 9721 Sheet #2. 97-LG, a low compression Springfield chassis, both run hard to Montreal and back by Mr. Platford in hot summer weather. [Table for chassis 78-NE] 78-NE Brand of Oil: A- Mobiloil B Heavy Body, Mileage: 374, Brand of Gasoline: Gulf & Socony, Induction Pipe: Hot, Choker System: Derby Pilot Jet, No. of Times Used: 6, % of Gasoline in Crankcase Oil: 5.4 Brand of Oil: B- Do, Mileage: 419, Brand of Gasoline: Socony & Purol (Canadian), Induction Pipe: Heated, Choker System: Springfield Choker, No. of Times Used: 8, % of Gasoline in Crankcase Oil: 5.8 Brand of Oil: C- Do, Mileage: 114, Brand of Gasoline: Low Flash (Canadian), Induction Pipe: Heated, Choker System: Not Used, No. of Times Used: Not Used, % of Gasoline in Crankcase Oil: 3.6 (In test "C" greatest dilution occurred though mixture lever was kept on extreme weak side all the time.) [Table for chassis 97-LG] 97-LG Brand of Oil: A- Texaco Extra Heavy, Mileage: 337, Brand of Gasoline: Gulf & Socony, Induction Pipe: Heated pipe for 50% of run. Then heat cut off but pipe left otherwise unaltered, Choker System: Derby primer, No. of Times Used: 2, % of Gasoline in Crankcase Oil: 2.06 Brand of Oil: B- Do, Mileage: 441, Brand of Gasoline: Low Flash (Canadian) & Socony, Induction Pipe: Heated pipe, Choker System: Derby Pilot Jet, No. of Times Used: 6, % of Gasoline in Crankcase Oil: 2.59 (These results are better than obtained on 78-NE high compression engine, although the pistons on 97-LG had less mileage to their credit.) With further reference to the effect of the various choker schemes on crankcase dilution, we have obtained the following results by cutting off the gasoline supply and allowing the engine (driven by the starter motor) to exhaust the float chamber. Engine speed about 90 r.p.m. Derby primer - throttle closed ............. 12 seconds Throttle open in ordinary position for starting .................. 50 " [Red stamp across the center of the document: COPY] | ||