Inspection Checkpoint: Trenchers
I NSPECTION CHECKPOINT
by Marcia Gruver
How to inspect a used rubber-tire trencher
Rubber-tired trencher inspections are straightforward affairs, with little of the complications seen in other machine types.
“
e usually see 200 to 250 hours a year on a machine this size,” says Steve Howard, used equipment manager, Vermeer Southeast Sales & Service, Birmingham, Alabama. Our inspection machine, a 1999 Vermeer V-5750, was low on that scale, clocking in at 855 hours. “Utility users tend to put fewer hours on a machine than contractors,” Howard explains. Contractors typically interested in this size and age of trencher do short runs and small jobs, such as plumbing or irrigation work. “They can get good value – this machine would cost about $7,500 compared to a $40,000 new trencher – and it will last them a long time,” Howard says. Key inspections points include: Engine: Perhaps because our 57-horsepower inspection machine had such low hours, Howard didn’t see anything in this area that concerned him. Steve Howard He looks for paint discoloration, especially on the engine head, which could tell the story of an engine overheating. If the engine is water cooled, he also suggests inspecting the radiator fins for damage. In addition, he highly recommends pulling an oil sample. “It’s inexpensive and it will give you a good idea of what’s been happening,” he says. Hydraulics: Most of today’s trenchers are hydrostatic, with hydraulic pumps running the motors for both the ground and trencher drives. Howard recommends
W
cranking the machine up and checking hydraulic pressures by putting a test gauge on the hydraulic test ports, then deadheading each system. And pull another oil sample. “You can’t just look at the trencher motor, for example, and determine the condition,” Howard says. “You’ve got to do the oil sample and pressure test.” Operational checks: While the machine is running, make sure the hour meter is running properly and the alternator’s charging. Put it in forward and reverse to observe how it tracks and steers. Operate the trencher, and see if you can trench with it. Engage the chain, observe how it runs on the sprockets and idlers and make sure it’s not loose. Listen for any skips – the chain should run smoothly and a skip could indicate a sprocket problem or bad chain link. Run the chain in forward and reverse. Lower the boom and pick up the back end of the trencher about 6 inches, looking for play in the pivot rings as they take on the weight of the machine. If you don’t have the time to check out a machine in question, Howard suggests hiring a local mechanic to thoroughly put a machine through its paces. Also check with your dealer buddies and other contractors – because of reported problems, certain makes and models may not have the resale value the buyer is asking. Trencher: This is what Howard calls “the money end.” Look at the drive sprocket, noting any wear that would require replacement. The chain on our inspection machine had more age than wear – the teeth were badly pitted, and the rollers had a great deal of rust and corrosion. “I would plan on replacing this chain sometime in the near future,” Howard says.