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 from France detailing engine oil leaks, crankcase ventilation issues, and tyre wear problems.
| Identifier | ExFiles\Box 82\1\ scan0069 | |
| Date | 28th March 1933 | |
| X4553W1 To Hs{Lord Ernest Hives - Chair} From GWH{George W. Hancock - Head Chateauroux} Hotel de France Chateauroux Indre B E N S P O R T The engine showed no sign of tightness during yesterdays mileage. The acceleration figures show a falling off from 70 to 80 MPH. The pistons fitted were approx. 1 oz; lighter. The bedding was even after lapping in, no trouble was experienced in the fitting, the instructions were carried out. We found a small blow hole in the machined part of the bottom tank of the radiator, at the O.S. We had reported a slight leak of water from this anchorage. We are loosing a quantity of oil from the rear of the engine into the clutch pit. We have tried various ways of increasing the air pressure in the clutch pit but have not materially reduced the oil leak. It would appear that at high speed the crankcase is not sufficiently ventilated. We cannot increase the suction on the present breather pipe, as by doing so a large amount of oil is drawn out. In our opinion the breather pipe is too small in diameter. A larger dia. breather would allow the air to expand more and reduce the velocity. We should assume then that less oil would be drawn out of the crankcase. In previous cases with the 25 HP we have run with the filler cap off the oil filler with no detrimental results as regards oil coming out, but very definite results with regard to curing oil leaks from front of engine and into clutch case. The car has left here for Calais with A.B. Roberts and R.{Sir Henry Royce} Pattinson. The instructions given to them is to run steady down to Calais to give the pistons a chance of settling down. Roberts is to return with PN.{Mr Northey} Pattinson to return by train to Paris where he will wait and pick the car up again. Thursday morning, Roberts and Pattinson will leave Paris, call at the Montlherry track and do as many miles as possible during the morning, return to Chateauroux in the afternoon. We have run into low speed wobbles as you will have seen by the daily reports. We assume the reason of this is due to the wear of the front tyres. The tread had become flat and from previous experience we know that the steering becomes worse with worn tyres. We have fitted the car up with a complete set of new tyres for PN{Mr Northey}'s run. This has used up all our tyres. We have no further replacements and those tyres will not last the test out. Will you please therefore send us another six tyres. [Signature] G.W.H. | ||