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).
Instructions for the use and maintenance of Alemite fittings and the grease compressor.
| Identifier | ExFiles\Box 76\4\ scan0288 | |
| Date | 3rd June 1921 guessed | |
| Alemite Fittings Each fitting is a check valve formed by a steel ball, held in place with a spring. Sufficient space is left between the ball and the inner wall of the fitting so that clean grease will pass through easily. Once the bearing is filled with grease and the pressure relieved, the spring forces the ball back into place, closing the opening. Thus the fitting performs the double function of retaining the grease and keeping out the dust. If a poor grade of grease is used, small particles of dirt and other foreign substances are apt to collect between the inner wall of the fitting and the ball with the result that the fitting clogs up and the grease cannot be forced through. It is then necessary to take a common pin or a piece of fine wire and dig the dirt out from around the ball so that it will seat properly and a clear passage is opened up through the fitting. In the event that it is still impossible to force grease into a fitting that has been thoroughly cleaned, the trouble must lie in the hose coupling. By running a small wire through hose, this congestion is quickly relieved. To Fill Compressor FIRST disconnect hose from compressor. Do not do this by twisting flexible hose, as this is most injurious. Next unscrew the removable head (A). Then screw out piston rod (B) so that the leather plunger (C) is drawn up inside metal cup (D). This not only protects the plunger but allows you to screw head on after compressor is completely filled with grease. This is a very necessary precaution, for, if not heeded, the grease spreads the leather plunger and it cannot be started back into the cylinder. With an improvised paddle you can fill cylinder (E) with some good lubricant. Grease must be absolutely clean and free from all foreign substances. Always remember that grease is cheaper than bearings. To avoid air bubbles and to get the full capacity of the compressor, jar and shake grease down by tapping the cylinder on some convenient box or wood bench. After filling the compressor the first time, or in case the leather plunger is dry, it is a good idea to spread and soften plunger by rubbing a small quantity of grease around the inner and outer flange before drawing it back into the head. This prevents grease from passing back into the cylinder when high pressure is being applied. It is a good idea to place a small quantity of grease on plunger screw | ||