If a shaft spinning at 20,000 rpm can pose a sealing problem then what about one doing 120,000 rpm or even, dare I say it, 240,000 rpm? A simple enough question, you might say, but before answering it we need to understand the application and the desired effectiveness of the seal required. A crankshaft oil seal for instance needs to be 100% reliable under all conditions. This is because in the mind of the customer, it takes but a single drop of oil to constitute a failure. In the case of a...
At the recent Monza World Superbike round, I asked Marcus Eschenbacher, crew chief to Cal Crutchlow at Sterilgarda Yamaha, about their choice of exhaust configuration. As many who work in Formula One or study it will know, the exhaust systems on each side of the engine are arranged in a 'four-into-one' collector with four primary pipes coming together in a single collector on each side. The arrangement is often abbreviated to '4-1', denoting four pipes converging into one...
We have, in previous articles, looked at the importance of correct pre-load for fasteners, and this is especially important where there are cyclic loads involved that might causes fatigue failures. One of the more reliable ways in which we can tighten a fastener is to measure the extension or 'stretch' of a given bolt or stud, and for a con rod, this is indeed the way that the vast majority of engine builders will work. Knowing the load versus extension relationship of the bolt means...
As the world awaits the new, expected to be revolutionary, engine rules for Formula One, last winter an altogether much quieter revolution was taking place. For tucked away on pages 56 to 58 - towards the back of the 67-page F1 Technical Regulations document - was Article 19, relating to the fuel used in the formula. To claim it is a revolution is no hyperbole. For while in both sets of regulations - the 2009 version and its updated 2010 successor - the purpose of the Article is "to...
When I was a lad, my old dad always used to say, "Change your oil regularly, son, and you'll rarely have any engine problems." Good advice indeed at a time when the statistic that 90% of all engine wear takes place in the first few seconds of engine life wasn't even invented. So every 2500 or 3000 miles, I forget which, I would dutifully warm the engine of my ten-year-old Triumph TR4 and drain the oil, allowing at least 30 minutes for as much of it as possible to drip into...