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).
Inspection report on a faulty G.S.SC. petrol pump detailing the cause of failure, repairs undertaken, and further testing.
| Identifier | ExFiles\Box 96\1\ scan0282 | |
| Date | 18th February 1938 | |
| To By.{R.W. Bailey - Chief Engineer} from Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems} G.{Mr Griffiths - Chief Accountant / Mr Gnapp} MX.{John H Maddocks - Chief Proving Officer} Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems}1/MH.{M. Huckerby}18.2.38. 361 PETROL PUMP OFF 3.AZ.74. No.RB.{R. Bowen}636. This is a G.S.SC. petrol pump and had not been inspected at the works. The complaint Report states recurrent failure of one unit and appears to be a case in which the trial switch has been used and possibly prevented ultimately a complete failure on the road. The R.H. unit was working well with a good delivery on the test rig. The L.H. unit had a laboured action and after a time stuck. There was considerable sideways movement on the toggle gear. The setting of the pump was dependent on how the load was applied. It was applied on one side the points did not break, but if on the opposite side the setting was correct. The pole piece was .005" out of centre and the roller wear in two cases .002", there was slight evidence that the armature had been lightly fouling the pot. This eccentricity combined with the roller wear would throw a side thrust on the contact mechanism. This pump must have been one of the first G.S pumps modified before we tightened up the limits on the concentricity of the pole piece to .003", and we suspect the rollers were slightly below the low limit which would aggravate the trouble. We centralised the pole piece with the end cutter and rebuilt with the same rollers and diaphragm. The side thrust on the toggle disappeared and the pump gave a very good delivery on the rig. We are inspecting the pump throughout and after a satisfactory test will return it to Cricklewood. We have completed 500 hours on the rig with a pump fitted with a positive guide to the spindle to take all side thrust off the toggle mechanism. Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems} | ||