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).
List of technical points and comments regarding bonnet and radiator components.
| Identifier | ExFiles\Box 72\2\ scan0124 | |
| Date | 9th July 1925 guessed | |
| -5- 6. Ferodo bonnet strips. The fixing of the Ferodo on the bonnet strips is not definitely settled. On 7-EX there were two schemes of lacing the Ferodo bon.rest. we await further experment and report. 7. Guide for bonnet lock. There is no guide for the bonnet lock. It is therefore difficult to close the bonnet so that it will lock properly. A guide appears necessary. 8. Bonnet handles. The shape of the bonnet handles has been changed. We prefer the old type. We concur with Hs{Lord Ernest Hives - Chair}'s remarks. Not considered as good as the old ones. 9. Rivetting of bonnet. Countersunk rivets are used on the bonnet in place of the snaphead rivets which have been a characteristic feature on the H.R.for so long. The Works point out that the counter-sunk rivets are more difficult for them to make a neat job. Also on the present standard bonnet, when it is opened, the snaphead rivets butt together and prevent the paint being marked. Snaphead rivets are preferred. We do not wish to alter the well-known appearance of the H.R. more than absolutely necessary. 10. Size of radiator. The radiator is 1.1" higher than the 'V' Series. The length of the radiator tubes however, have been reduced to 350" so that the actual area of the radiator remains approx. the same as 'V' Series. Noted. We had hoped that the new radiator would have greater cooling capacity. 11. Radiator cap. The radiator cap has been modified. It is arranged that when the radiator cap is screwed on it opens the vent & to the radiator which is set at the correct level. This means than the radiator cannot be over-filled or at least, if it is overfilled, the level is automatically correct when the cap is screwed on. The radiator cap has slightly different dimensions from the present standard. Noted. (The general proportions of hexagon nut as compared with size of cap of old one is preferred). We are most anxious not to alter the appearance. | ||