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).
The testing and troubleshooting of a petrol pump, part number E.25588.
| Identifier | WestWitteringFiles\N\July1925-September1925\ Scan323 | |
| Date | 29th September 1925 | |
| R.R. 493A (50 H) (D.D. 31, 12-6-25) J.H.D. EXPERIMENTAL REPORT. Expl. No. REF: HS{Lord Ernest Hives - Chair}/AR/LG29.9.25. R-R PETROL PUMP - E.25588. A new type R-R petrol pump was submitted for test on 4-C-4 on the hangar. Its supply was drawn from a tank 8 ft. below the level of the pump, delivery taking place into a tank 16 ft. above the level of the pump. The engine was run for 1/2 hr., but during that period no petrol was delivered by the pump. The teeth of the pump pinions were then oiled and both suction and delivery pipes primed with petrol, but the pump still refused to deliver petrol. The pump was then dismantled and the relief valve E.25573 thoroughly cleaned, ground in, and checked with blue, to ensure a perfect seating. The engine was run a further 1/2 hr. but pump still refused to function. The relief valve disc and its spring were then removed, and the bye-pass to the suction side plugged up. With this modification the pump began to deliver petrol almost immediately, and put up a good pressure at a 16 ft. head. The test was repeated with an identical pump, and similar results obtained i.e. with the pump standard no delivery took place, but on removing relief valve and plugging up bye-pass, delivery began immediately. These tests indicate that the relief valve is leaking very badly. To confirm this the relief valve chamber cover plate was removed and replaced by a cross piece which served as the relief valve spring anchorage and at the same time allowed the action of the contd :- | ||