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).
The performance, issues, and failures of a vehicle's lubrication system, including leaks, seasonal effects, and component failures.
| Identifier | ExFiles\Box 27\1\ Scan037 | |
| Date | 1st February 1929 guessed | |
| - 3 - We shall shortly use the "DGB" type tank with pressure filter shown in A-14163 attached, having run this about 25,000 miles without trouble. (8) Leaks. If leaks occur from any cause the pump handle goes down visibly too fast and one finds a pool on the floor. If air enters the system because of a leak one feels that the pump handle does not pull back "solid", on the first stroke, but squeezes the air bubble out at the nearest drip plug and goes solid at the second stroke. We have often found this to happen but it does not appear to do any harm, and by watching around the system for bubbles blowing out of a bearing, one can generally find it (if sufficiently interested). As a general rule air leaks are not encountered and the pump handle leaves the hand without flying back except in very cold weather as described above. (9) Winter and summer. Have referred to this above under Oil. In winter the drip plugs under the bonnet tend to get more than their fair proportion of oil. We therefore hold these "warm" plugs to the small side. This is another argument for the morning operation of lubrication and the use of an oil which will discharge a pump full say in 5 minutes maximum on a cold morning, since then the oil flow is over before the engine warms up enough to let all the oil go at the warm plugs. In the summer in the event of very lavish use, there may be complaints of cars dripping oil, but the only criticism we have is on cars with internal valances where oil has dripped from the rear spring pivot on to the running board or valances Failures. We have had a large number of small incidental "failures" of the system, principally due to design, which I will describe - (1) The pump is fitted with a floating inlet valve so that in the event of the tank emptying, the pump cannot force air into the line, but just flies back and does nothing. So one has an excellent indication to fill up the tank. Failure of the system from this cause is therefore not to be feared. (2) Broken pipes. We have had a lot of trouble in getting brass pipes bent to shape without longitudinal cracks. We have no evidence that these cracks form in use, but they have sometime not been discovered till the car is in use. We now pressure test these pipes with 80 lb. water pressure. Mr. Bailey has full particulars of the brass pipe which gives best results. -continued- | ||