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).
Issues and solutions for petrol spillage from filler caps on Phantom II & 20/25 HP models.
Identifier | ExFiles\Box 17\5\ Scan193 | |
Date | 19th April 1933 | |
x7460 To E.{Mr Elliott - Chief Engineer} From Hs{Lord Ernest Hives - Chair}/Wymn. C. Hs.{Lord Ernest Hives - Chair} By.{R.W. Bailey - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Wymn.1/KT.19.4.33. PETROL TANK FILLER CAPS. P.II & 20/25 HP. Complaints have been received that the latest type of petrol filler cap is still giving trouble with regard to petrol spilling. We have carried out tests on various cars and found that (a) when taking a right hand bend quite a large quantity of petrol was forced through the air vent pipe from the top of the tank into the sleeve in the filler pipe filling up same and consequently spurting out of the 2 - .125" air vent holes on to the bodywork. (b) We also found that the leather washers fitted inside the cap were inclined to leak after a time - due to the washer squeezing up and not being pressed tightly on to the face of the filler pipe. Our tests have also proved that when the petrol surges up the filler pipe, it always follows the outside of the pipe (as per sketch). Therefore we have placed the air vent holes on the inside of the pipe and to prevent the petrol that strikes the leather washer from leaking through these holes, we fitted a small baffle plate which can be sweated all round and have 2 - .125" vent holes drilled in the bottom (see drawing). To overcome trouble (a) we have deleted the sleeve entirely. This does not affect the air release (the tank can be filled as fast as the petrol pump can be worked without any air trapping), we actually pumped 5 galls. of petrol in 12 secs. Re. trouble (b) we suggest a small steel washer should be fitted at the back of the spring plate thus increasing the tension applied to the leather washer when in closed position. We would also like to suggest for future cars that the filler cap should be so hinged that when closing same the washer would sit squarely on its seat before being finally compressed instead of the present fitting in which the hinged side of | ||