While it might be the aim of many engine designers to minimise the chance of any oil leakage by dispensing with the humble rotating shaft seal, it may not always be possible or even desirable. At any point where there is a mechanical take-off in the form of a rotating shaft, an oil seal will need to be present and while race engine designers try to minimise these occurrences, for the rest of us wishing to improve existing OE equipment or re-engineer old engines, that option simply does not...
Last month we looked at the problem of how to contain excessive heat given off by hot exhausts. The problems this heat causes affect not only the engine, but also other systems, particularly electronics. In addition to wrapping or coating the exhausts, we looked at the concept of bagging or blanketing. Heat shields were mentioned and in Formula One at least these are commonplace, being lightweight and effective in shielding the engine from radiative heat transfer. The problem with wrapping...
After having calculated bolt stiffness, or measured the load-deflection curve directly, the best way to calculate pre-load is to measure the extension of the bolt directly. This method is preferred for con rod bolts and all con rod and bolt suppliers generally recommend this method. The fasteners require design features to allow measurement with a special micrometer. This method is impossible for fasteners in blind holes. For large fasteners in blind holes the extension can be measured...
Love them or hate them, the two-stroke engine is in many ways far superior to its 4-stroke rival. Specific power, specific weight, manoeuvrability, cost of manufacture, ease of maintenance, durability, NOx emissions and even fuel consumption in the case of smaller engines, can be far superior to its less controversial 4-stroke brother, but why then don’t we see more of these engines in competition? With one strike for power and one to wear it out as opposed to one of power and three...
It is surely an obvious statement of fact that what goes in, will eventually come out again – somewhere! Filling the bath with water and then watching it drain away again afterwards is an example. The joy of watching the bank balance rise at the end of the month and then tearfully watching it ebb away again in the weeks following, is another. But unlike these examples, which would appear to happen without any effort at all, the task of extracting the oil out of an engine comes at a...