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).
Ignition failure on an experimental Phantom II chassis due to the H.T. wire from the coil to distributor breaking down.
| Identifier | ExFiles\Box 168\1\ img108 | |
| Date | 9th July 1931 | |
| X6117 Ry. from Hs{Lord Ernest Hives - Chair}/HEW. Hs{Lord Ernest Hives - Chair}/HEW4/AD9.7.31. H.T. WIRE FROM COIL TO DISTRIBUTOR. We have had another case of ignition failure on an experimental Phantom II chassis due to the short H.T. lead from the centre terminal of the distributor to the ignition coil breaking down where it had been touching the tappet cover. The electric stress and local brush discharge effects on the cable dielectric tending to cause deterioration of the rubber and consequent breakdown, are much increased where the rubber is at a high temperature, hence the necessity to avoid the possibility of a hot earthed metal part coming into contact with the H.T. cable. We proved this some time ago in the laboratory. We understand GWH.{George W. Hancock - Head Chateauroux} had a similar case recently which was mentioned to you and we should be glad to know if you are ensuring that this H.T. wire can not in any circumstances touch the cylinder head or tappet cover. Hs{Lord Ernest Hives - Chair}/HEW. | ||