Evaluating Used Equipment: Part 2

Aug. 31, 2020
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This week we continue our three-part series from Volvo Construction Equipment and their experts offering important information on used equipment. Part 2 was written by Adam Sieg, Uptime Support Center Manager, Volvo Construction Equipment. Adam has been with Volvo for 10 years, starting out as a product expert for skid-steers and providing technical support on a global level for Volvo dealers. He has past experience in technical support, sales, and product and sales training with dealers and customers. In his current role, he manages a team that provides technical support for Volvo dealers in North America in order to provide uptime, reduce customer downtime, and help dealers perform quick and efficient repairs on Volvo machines.


In times of uncertainty like this, you are likely looking to maintain or repair machines faster and cheaper. You may opt to do it yourself, and in many instances—especially if you have a skilled and experienced technician—it can be a smart move. But for some repairs, there’s the potential to cause further damage to other components or systems, which could end up costing you a lot more time and money in the long run.

So, which construction equipment maintenance and repairs are good for DIY, and which ones really require an experienced dealer service technician with the right tools? Here are some common repair and service tips that can help you decide.

Common DIY Machine Repairs

  • Safety first. Before you begin, you should always follow all safety requirements as outlined in your Operator’s Manual. Some OEMs have equipment service position videos that are helpful, too.
  • Routine maintenance like oil changes, filter changes, and greasings. These are pretty straightforward services you can do in your shop — in fact, you should be greasing your machines on a regular basis. Maintenance tasks like these are all called out in your operator's manual.
  • Minor welding (depending on the location on the machine). In most scenarios, it’s okay to weld on areas that don't require exact welding specs. For example, an older bucket that cracked and requires a minor weld to repair it. Even if the weld fails, it's not going to cause major issues with your machine. But on more critical areas like frames, booms, arms, or the ROPS assembly, it’s always advisable to talk to your dealer first. Your dealer may say it's something you can do on your own, or they may ask that you bring the machine in to follow specific OEM instructions. Always have safety top of mind before you decide to take on a weld yourself.
  • Minor wire harness repairs and changing of relays and fuses. If you find that some wires are nicked, cut or damaged, you can easily splice in something new — cleaning up corrosion and changing out relays and fuses is easy, too. Where you can get into major issues with the harnesses, though, is when extensive damage means it needs to be replaced completely. There are also some situations where connectors are damaged, and you need special tools to pull out and re-pin the connector. These kinds of repairs are better suited for a dealer.
  • Replacing some parts/components such as cylinders, pumps, motors and actuators that are simple to remove/replace. Components that bolt on—where you can unbolt it, bolt on a new one and attach a hydraulic hose or whatever you need—are relatively easy to do. It’s trickier when a set up requires a certain pressure spec that needs to be adjusted—for example, load-sensing pumps. If your technician isn’t trained on the procedure to hook up the gauges, he or she can cause other performance issues or damage other components.
  • Replacing wear items like bolt-on cutting edges, bolt-on bucket teeth, tires, stop pads, etc. These are tasks your technicians should be able to handle.
  • Hydraulic hose replacements. The main thing you have to be careful of is making sure your replacement hoses are the right specs—the right size, durability, and strength of the hose pressure rating.

There are also some common repairs that customers may think are DIY but end up costing them more time and money down the road. Here are a few of the more common ones: 

  • Injector repairs on newer systems. A smoking engine or a machine that seems to be running low on power can be an indication of an injector that’s not spraying fuel into the cylinder correctly. Tier 2 and Tier 3 engines have low-pressure injection pumps that are pretty straightforward — you just take them out and put new ones in with new seals, washers, etc. Experienced techs sometimes think that because they’ve done these older machine repairs, they can do it on newer ones, too. But in high-pressure common rail pump and injector systems, the pressure is extremely high — if you have a leak (or you don't have a pipe screwed on tight and you develop a leak), fuel comes out at incredibly high pressure and can cause injuries. These new injectors are also prone to contamination, which can easily ruin them.
  • Pump replacements without knowing the correct pressure settings, or replacing and not flushing the system. If you don't know the correct pressure settings when replacing a pump, it can cause serious issues. And if you inadvertently introduce contamination when replacing a pump and you don't know how to flush it, that debris may get flushed into something else. This could lead to other issues like needing to take out a valve assembly or continuing to have problems due to the contamination.
  • Not knowing ECUs need to be programmed. Hardly any ECUs come pre-programmed these days—they're usually blank. If you simply bolt in a new one and it’s not programmed with the required trim codes, you may think the ECU is damaged. You could be left with a machine that you can't start, and you have to either haul it in or have somebody come out to fix it. In most cases when it comes to ECUs, you're better off bringing them to the dealer who has the right tools to program them.
  • Buying off-brand parts and not getting the OEM parts warranty. Many parts replacements may seem similar but may not meet the performance requirement for your machine to function correctly. As an example, Volvo replacement parts are designed to perform the same as the original parts.

Machine Repairs & Maintenance Best Suited for Your Dealer

  • More complex Tier 4 engine work and engine after-treatment systems. High-pressure common-rail pump and injector systems help reduce emissions for Tier 4 engines. And with these systems, more computers are involved. Plus, after-treatment systems are more complicated because there are multiple components that all have to work together. A lot of times it's very difficult to troubleshoot where your problem is because it may be in a couple of different areas. Addressing one doesn't necessarily mean it's going to fix the system and you may have another issue that you didn't realize. Parts for these systems are also expensive, and if you replace a part that didn’t need to be replaced, it’s wasted money. Dealers often get a great deal of in-depth training to help them repair these systems.
  • ECU replacements. A lot of times customers feel like they’ve got an ECU issue and replace it when in reality the ECU isn’t bad—it's a wiring or connection issue, or something with the software logic where the ECU isn’t seeing an input or condition and is preventing the component from getting the right signal or a signal at all. If you find that you do need a replacement, however, you need specific tools to do calibrations, program injector trim codes, and/or program the machine type, model, and serial number. Dealers have access to a wide range of troubleshooting and guided diagnostic information that customers don't.
  • Transmission replacements. This job can take special tools that require calibration and, similar to ECU replacements, specific tools to do it. Remember, newer machines are more complex and more difficult to work on compared to older Tier 2 and Tier 3 machines.
  • Load sensing pumps. Again, there are tight windows of what’s acceptable and a dealer can ensure these requirements are met to prevent issues down the road.

For repairs like these, lack of expertise can add to repair time and costs. If it takes you hours more than what a dealer could do, you might end up costing yourself more money in the long run. It’s easy to get into an area that’s very complicated, and in the attempt to fix something, you end up damaging something else.

The best route is to discuss with your local dealer whether you can handle a repair and if there are certain required tools that you don’t have. Again, you should always follow all safety requirements as outlined in your Operator’s Manual. Careful consideration also has to be taken on whether the decision to replace a part or component is straightforward, or if there’s additional work that also needs to be done (such as pressure settings). Getting a dealer involved for these types of scenarios can save you a lot of time and money down the road.