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).
Engine seizure tests under cold starting and rich mixture conditions.
| Identifier | ExFiles\Box 87\2\ scan0053 | |
| Date | 17th April 1935 guessed | |
| -2- Cold Starting. Our next test consisted of running at full throttle at 4,000 r.p.m. with the engine cold, in this test we started up and ran the engine up to 4,000 r.p.m. full throttle immediately the engine fired and before the oil could get to the bearings, but even this did not produce a seizure. We also tried the effect of running at low speed full throttle starting from cold in order to prolong the time of the oil getting into circulation, but we were no more successful than in our previous tests. Rich Mixture. We then decided to run a series of tests with a rich mixture, in the first test we flooded the carburetters and set the mixture control full rich and warmed up the engine in the normal manner, except that the mixture control was left in the full rich position the whole time, and again we were unsuccessful in producing a seizure. Our next rich mixture test consisted of running the engine with mixture set full strong at various speed from 4,000 r.p.m. down to 750 r.p.m. full throttle with the jacket water kept as cold as possible. Continuing our tests with rich mixture we then started up with the engine cold and the mixture set full strong, and carburetters flooded for several minutes before starting. Immediately the engine fired on starting up it was run at 2,000 r.p.m. full throttle and kept running for 20 minutes with the mixture set at full strong, and with the carburetters flooding continuously the whole time. This test was repeated with the engine running at as low a speed as possible, but without success in the way of seizures. Our next test consisted of running the engine at various speeds with one cylinder not firing and with the mixture set full rich, the carburetters were flooded before starting in order to get as much wet fuel as possible into the bore that was not firing. We ran the engine in this manner at various speeds for 2 hours. We did one further test with one cylinder not firing, and in this test we ran the engine, after flooding the carburetters, full rich at 500 to 750 r.p.m. for 10 mins. in order to again fill the cut-out cylinder with as much wet fuel as possible, in order to wash as much lubricating oil as we could from the cylinder walls, and at the end of the 10 mins. we opened the engine up to 2000 r.p.m., but again without the slightest sign of a seizure. | ||