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 condition and failures of various engine components following a 10,000 miles test.
| Identifier | ExFiles\Box 4\9\ 09-page201 | |
| Date | 18th January 1926 guessed | |
| -3- Exhaust manifold pipe & fittings; (continued) It has been necessary to form a new flange. The small bracket holding exhaust pipe to frame has broken off. This particular bracket has always broken on the 10,000 miles test. Engine suspension. The engine suspension has remained in good condition. Carburetter & fittings. The air valve cover worked loose during one day's run, it has remained firm since tightening up. The air valve is in good condition Carburetter floods after pulling up, we are of opinion that this is due to the heavy petrol that is in the induction pipe which runs back into carburetter after stopping. We have examined petrol level, float, needle valve and weight, and there does not appear to be any of these out of order. Fan bracket, fan & fan belt. It has been necessary to take out one link out of fan belt as the adjustment was almost taken up. The fan and bracket have given no trouble. Magneto & drive. X.3851. We have had occasion to run on magneto, at low speeds it causes misfires, examination of points shows them to be making poor contact, only half the face of points being in contact. The drive is O.K. Dynamo. Y.4610 This has not given any trouble, but the output is low. At maximum speed it gives 5 amperes; at low speed it gives 2.5 amperes The brushes and gear have remained clean and the commutator looks in good condition. Oil pump. A new oil pump was fitted in Paris before starting on the 10,000 miles. The pump has holes drilled in bottom of gear teeth so as to feed oil to bearing. We have had considerable trouble with the oil pressure since the fitting of the pump. We first found that solder had adhered to the release valve guide and a small piece had become attached to the stem of the release valve, causing it to stick. We have since continually been taking the release valve out and removing hard spots from off the stem of valve, but we have not beenable to complete a run without the oil pressure failing. Our oil pressure would remain O.K. untill the brakes were applied; when the oil pressure drop to 5Lbs. and would not build up again for some considerable time. On one or two occasions the run had to be continued with an oil pressure of 15 lbs. We have taken pump down and found that the stem of release valve was cross binding. In the mean time we have refitted the old pump taken off to prove if there was any cause for the failures. This has so far given no trouble. It immediately builds | ||