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).
Promotional leaflet for E.R. sparking plugs, explaining their benefits, pricing, and maintenance.
| Identifier | ExFiles\Box 162\3\ img113 | |
| Date | 26th April 1938 guessed | |
| THE SPARKING PLUGS THAT COST NO MORE BUT.. OLD PLUGS WASTE POWER! The ignition of the fuel is probably the most important function in an internal combustion engine. The intensity of the spark plays a large part in determining the “completeness” of each explosion that takes place inside the cylinders, and therefore has a direct bearing on the actual power derived from the engine. A weak spark explodes the fuel so slowly that it is not all burnt up before the piston has started on its return stroke and the exhaust valve has opened to let it escape. The result is a loss of both petrol and power. A good strong spark, on the other hand, will explode the mixture quickly and cleanly, giving the greatest power per explosion, with no waste. This means better acceleration, more power on hills and more miles per gallon. You will appreciate, therefore, the importance of keeping your plugs in good condition. If your present plugs have been in your car for over 10,000 miles, they are probably causing a loss of efficiency in your engine. You may find this a little difficult to believe at first, but the truth is that plugs deteriorate so slowly that it is impossible to notice the very gradual loss of power. When you replug with E.R. you will be surprised at the difference in performance. KEEP YOUR PLUGS IN TRIM E.R. make no extravagant claim that E.R. plugs will never burn out or oil up, for indeed no plug manufacturer can honestly claim this. But if the type of plug is correct, plug trouble can almost always be traced to incorrect carburetion or a faulty lubrication system. An excess of oil reaching the combustion chamber due to worn piston rings or cylinder bores or too rich fuel mixture will foul the insulation of the plug with carbon. Excessive overheating and rapid electrode wear may be caused by a weak carburetter setting, leaks in the induction system or too early ignition timing. Providing the engine is in good condition, plugs will require little attention, although occasional cleaning is advisable. All E.R. mica plugs are detachable, and being provided with a metal to metal joint, can be taken to pieces for cleaning as frequently as desired, without fear of damaging the insulation, and with the assurance that a gas-tight joint can easily be obtained when re-assembling. When taking the plug to pieces, it is advisable to use a box spanner on the body while lightly gripping the gland nut in a vice. When detached the insulation should be wiped with a rag soaked in petrol, unless it is caked hard with carbon or fuel deposit, in which case it may be cleaned with a piece of smooth emery paper. The centre electrode and sparking points should also receive similar attention. Metal parts can be scraped to remove carbon. When reassembling, make sure that the copper internal joint washer is in position and is free from grit. ADJUSTING GAPS. For all normal engines a gap of 18 thousandth of an inch between sparking points is recommended, and this gap should be maintained by bending the side point towards the centre pin. It is important that the gap should not become too wide as an over-load would be thrown on the whole ignition system. Before the spark can jump from electrode to electrode the voltage has to build up to break down the resistance of the air in the gap. Obviously, if the gap is very large, a much larger amount of electrical energy is called for before the spark can jump across. Too small a gap will cause poor slow running. THERE IS AN E.R. PLUG FOR EVERY ENGINE MICA RANGE (detachable) 5/-, 6/-, 7/6. STEATITE RANGE (non-detachable) 4/-. E.R. PLUGS LTD. PEGAMOID WORKS, ANGEL ROAD, EDMONTON. N.18. Telephone: TOTtenham 3405. Ref No. 981. | ||