Other Publications

Construction Industry Poll

In the Magazine

Air Compressors

June 12, 2007 |

Air compressors are easy to ignore. Compared to your other equipment, they don’t cost a lot, they only do one thing and they’re so easy to operate that many contractors forget to look after them.

But a diligent equipment manager or owner should take care to treat these machines well. Otherwise the two primary and most expensive components, the engine and the air end, can fail prematurely. These are designed to last the full lifecycle of a compressor, but replacing them can put a painful dent in your cost of ownership, not to mention stop whatever work you had going until you can find a rental unit or new machine.

To find out more about what an air compressor maintenance best practices regimen would look like we talked to Don Holston, field service manager for Ingersoll-Rand compressors, and Butch Goodwin, rental shop supervisor for Cowin Machinery in Birmingham, Alabama. We used Ingersoll-Rand’s most popular compressor, the P185WJD, as a point of discussion, but most of the advice they gave us applies to diesel-powered compressors of all sizes.

Neglect is easy
Compared to the big equipment on a construction site an air compressor can seem insignificant. “They tend to get run over, beat up, scratched and sandblasted,” Holston says. “All of that has an effect. After a few years the machine probably looks terrible, even though the engine is far from worn out.”

Holston estimates 185-cfm and smaller machines see something less than 500 hours of use a year. The bigger machines can see 600 hours or more. A typical lifecycle – the point at which the engine or air end needs rebuilding – can stretch out to 10 years or more.

Oddly enough it’s the machines that don’t log many hours in a year that have a greater risk of a shortened lifecycle. This is due in part to neglect, but also to the fact that infrequent use is hard on a machine.

“With the machine going through heat up and cool down cycles you get moisture condensing in the compressor oil system,” Holston says. “Things like your separator element will develop condensate and promote bacteria growth in the element.” Left to sit for days or weeks with no activity, diesel fuel tanks also develop condensation and contaminants.

Machines that sit idle tend to get limited attention and field expedient maintenance. “The worst thing contractors do is put bad fuel or used oil in them,” Goodwin says. “They’ll grab whatever fuel is handy. Or if the low oil indicator light comes on, some contractors will just drain the crankcase of another machine and top off the compressor with whatever’s quickest.”