For high-stress parts such...
For high-stress parts such as the U-joints, regular replacement can prevent sudden failure. We know that all of the power the engine generates is transferred through the driveline and the hardest working part in that chain is this joint. The low cost of the U-joint makes the replacement maintenance an easy decision.
If there's any doubt of a parts age or quality, it is discarded. Replacement parts have become more complicated and expensive and production lead times have become longer. Anticipating what parts will need to be replaced has become a necessity. Dedicating team resources to parts management and life-ing is now considered very worthwhile in improving reliability and controlling costs.
A small team can learn from this professional approach and adapt these techniques to its simpler needs. Establishing a parts life-ing system in any team requires designating a conscientious crewmember as the parts life-ing coordinator. He or she must be willing to spend a few minutes each day to update the records and make them available for analysis.
This person should be a full-time worker who will be responsible for developing a logical numbering system, marking the appropriate parts and recording the parts changes as they are reported by other crewmembers. Each team member needs to understand why this process is important and help the coordinator keep the data accurate by calling out individual part changes as they are made. Having one person monitoring parts life-ing will help identify components that need inspection or are due to fail.
The most powerful tool in your pit box is the ubiquitous Sharpie. In the hands of your driver, it can make children smile and turn scrap into treasures. But, in the hands of your parts life-ing coordinator, it can give each part on the car a unique ID. The concept of unique ID is the fundamental principle of parts life-ing, because we want to track each part as it's installed, used, and removed so that we can assign its mileage to its record.
Many of the professional teams...
Many of the professional teams will keep an inventory of drive shafts that will be correct for each of the different racetracks at which they will race. Different cars may need different lengths and/or diameters and wall thickness designs. It's imperative that each shaft be well labeled and documented to prevent an error in installation.
A unique ID can be as simple as "Part #12" or as complicated as a street car's VIN number with each digit representing specific information in coded form. The unique ID can be written, stamped, engraved, etched, or attached to the part. All that matters is that the marking is legible, hard to deface and it will survive in the environment of heat and solvents it will encounter.
A parts record can be as simple as an index card for each part, a small computer spreadsheet or as elaborate as an expensive software system. As we saw in Driveshaft 102, some teams just write each mileage directly on the driveshaft. The size of your team and capabilities of your crew will determine what is best for you. Start with a simple card system and then expand it as your needs grow into a loose-leaf notebook or a spreadsheet.
If you tried to record all the mileage you drove in your street car in a month, it would be a tedious task to make dozens of entries. But your race car and its parts may only be used once a week in several short sessions and your crew chief is probably already keeping a lap chart of every mile run.
The life-ing coordinator needs to be alert to any changes of the components he is monitoring. When a change occurs, he simply needs to note when the change was made and the unique ID of the old and new part. At the end of the event, he can review the crew chief's practice and lap charts and determine the appropriate mileage to assign to each part's record.
At its simplest, you can monitor a chassis, an engine, a transmission, or a driveshaft. The racing driveshaft is a great example for learning this process because it has high initial value, a reasonable projectable service life and dire consequences if it fails. Once you get the rhythm of the activity, your life-ing system can grow to monitor any parts that have a predictable service or replacement life.
Fuel pumps, alternators, quick-change gears, axles and driveshafts are all critical components that seem to fail suddenly and unexpectedly. Preventing any one of these failures is reason enough to implement this system. Parts like spark plugs, brake pads, and tires are replaced regularly anyway and don't need to be documented.