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).
Letter from AC-Sphinx Sparking Plug Co. Ltd. about the test results of a clogged and split oil filter.
| Identifier | ExFiles\Box 135\3\ scan0265 | |
| Date | 6th April 1938 | |
| 1139. AC-SPHINX SPARKING PLUG Co. LTD. DIRECTORS: N.F.Stockbridge, W.O.Kennington, C.J.Bartlett. Telegrams: SPHINX,DUNSTABLE. DUNSTABLE, BEDS.,ENGLAND. Telephone: DUNSTABLE 360. Our Ref. DBB/DJG Your Ref. 6th April, 1938. Messrs. Rolls Royce Ltd., DERBY. Rm{William Robotham - Chief Engineer} For the Attention of Mr. L. H.{Arthur M. Hanbury - Head Complaints} Swindail. Dear Sirs, Oil Filters. In reply to your letter of the 4th instant, the contents of which we have read with interest, we must apologise for some little delay in letting you have results of our tests, but these have now been completed. The used Oil Filter had very little flow indeed, and from all practical points of view appeared to be nearly clogged, which is borne out by the fact that final weighing of the Filter element after dismantling proved the used Filter to be quite considerably heavier, but we are extremely puzzled to know how with originally clean oil the Filter can have become clogged at such an early stage. We wonder whether there was any peculiarity about this particular engine which will account for this happening, and would be interested to know if you have any suggestions to make regarding this behaviour. The principal point, however, which we set out to investigate was the split of the Filter case, and in this connection it was not until we raised the pressure to something like 150 lbs. per sq. in. that we were able to prove leakage, though this would of course have been much more apparent after a longish run on the car with the oil at a fairly high temperature. Upon dismantling the Filter, we found a perfectly clean split extending from the edge of the half pressing to about 3/8" away from the seam. This was undoubtedly caused in the original draw, and can only have AC Air Cleaners - AC Clocks - AC Fuel Pumps - AC Oil Filters - AC Oil Gauges - AC Plugs - AC Speedometers - AC Windscreen Wipers. | ||