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).
Test report detailing issues with the water system, carburation, and piston wear at specific mileages.
| Identifier | ExFiles\Box 91\3\ scan0207 | |
| Date | 8th October 1935 | |
| ( 2 ) Oil was first noticed in the water system after a mileage of 2,300, a slight leak having developed in the oil heater matrix. No water entered the oil system. Considerable quantities of water was lost from the system during the beginning of the test, via the steam pipe from the Radiator. At a mileage of 6,800, N° 2 Con-necting rod bearing failed, the white metal melting out. CARBURATION. FOUR CARBURETTERS IN THE VEE TO LOP E 87344 LEC 4706 4712 SV. 9. NEEDLES. The mixture control was heavy to operate and the action was uneven. The main jet return springs were reduced from 5 lbs. load to a 3 lb. load. No improvement was obtained. The chief cause was a jamming action between the small pinion and the rack on the main jet actuating rod. We complained of the heaviness of the acceleration pedal load. It required 7 lbs. for a third of the throttle opening and 15 lbs. to keep the throttle full open. A memo. E/PSN.5/MN.8.10.35 was received, giving a modification LEC 4751 for a lower rating throttle springs. We did not test this scheme, as we did not receive the springs. The Carburetters were seldom free from flooding. It was not possible to switch on to take a reading of the Petrol Tank whilst filling, without one or the other Carburetters flooding, making it difficult to start, besides the volume of unpleasent mixture being ejected through the silencer. Before fitting the SV.9. needles, there was a hesitation to start with a moderately hot engine. The vent scheme to the air silencer with considerably lower air temperatures during the tests, overcame the strong mixture trouble experienced during our previous test. When the engine was dismantled for the rod failure, we found two of the air pistons in a gummy condition. This is caused by the colouring matter used in the petrol. CARBURETTER AIR SILENCER LEC 4706 - 4712. No trouble was experienced with the fixing of the air silencer. It effectively silenced the roar of the Carburetters. PISTONS. LOP E 86706 LEC 4617 EX 19713 FULLY SPLIT TYPE. When the pistons were dismantled at a mileage of 6,800, they were examined for cracks etc. No cracks were found. The bedding of the skirts was poor. There was evidence of them having collapsed. The inner portion of each side the slot, showed no bedding. At the top of the skirt, fairly heavy bedding was noticeable. A peculiar feature was that the top ring of N° 1 & 3 pistons of A side was broken .875" from the split of the ring, also with N° 2 piston on B side. | ||