Fifteen years ago, an operator spent the first twenty minutes of every shift walking around the machine with a manual grease gun, forcing moly into the bucket pins and the boom joints. Today, almost every new excavator and wheel loader comes with an Automatic Lubrication System (ALS) installed at the factory. While these systems have drastically reduced the daily manual labor, they are creating a hidden epidemic of catastrophic pin failure.
An ALS consists of a reservoir, a pump, and a network of plastic or nylon tubing running to every pivot point. The ECU triggers the pump at set intervals, forcing grease through the lines. The problem is that operators and mechanics have completely stopped visually inspecting the pins.
In harsh environments, the tubing can chafe against the boom and burst, or a fitting can plug with debris. When a line bursts, the pump happily cycles, pumping expensive grease directly onto the ground or into the engine bay. The bucket pins that the line was supposed to serve receive zero lubrication. Because the operator no longer walks the machine, they don't notice the burst line or the dry pin until the bronze bushing has welded itself to the steel pin, requiring a massive, expensive torch-cutting operation to replace. Furthermore, if the pump reservoir runs dry and isn't refilled, the pump pushes air into the lines, trapping the remaining grease behind an air pocket. The ALS is a fantastic tool, but it has bred a dangerous complacency that is destroying undercarriages and front-end linkages.
