Comment inspecter les composants d'équipement d'occasion et éviter les mauvaises surprises coûteuses

L'achat de machines d'occasion est un excellent moyen de compléter votre parc d'équipement, et si vous savez quoi observer (et quelles questions poser), vous aurez l'assurance que votre nouvel équipement sera sur le chantier et non à l'atelier.

Ce n'est évidemment jamais garanti à 100 %, mais voici quelques conseils pour inspecter certains des composants les plus critiques d'une machine d'occasion et vous assurer que son état correspond au prix demandé :

• Demandez qui était le propriétaire de la machine : Il est tout à fait normal pour un acheteur de demander qui était le propriétaire de la machine, où elle a été utilisée et pour quel type d'application; n'hésitez donc pas à poser la question. Savoir d'emblée où et comment elle a fonctionné vous aide à cibler les éléments à examiner de plus près. Par exemple, si la machine a été utilisée dans un milieu corrosif, vous voudrez vérifier la présence de corrosion excessive. La rouille commence généralement à se former sous les passages de roue, sur les raccords de flexibles, sous les châssis de chargeuse, sur les jantes et sous le châssis. Les machines utilisées dans le recyclage de ferraille, la gestion des déchets ou l'exploitation forestière subissent généralement des conditions plus rigoureuses et une usure accrue; vous devrez donc inspecter attentivement les composants comme les pneus et la transmission. Si une pelle sur chenilles a travaillé dans le sable plutôt que dans la terre, le train de roulement s'usera davantage. Commencez toujours par vous renseigner sur le lieu et le type d'utilisation de la machine pour orienter la suite de votre inspection.
• Pneus : Visionnez cette courte vidéo pour obtenir de précieux conseils sur la façon d'inspecter adéquatement les pneus des chargeuses sur pneus. Tout comme pour les chargeuses, les pneus de tombereaux articulés nécessitent la même évaluation. Vérifiez les sculptures dépareillées, la profondeur inégale de la bande de roulement ainsi que les entailles sur les flancs ou la bande de roulement.

• Transmission: Most transmissions will last up to around 8,000 hours before you start having to make repairs. One thing you always want to check for is leaks, but you also need to operate the machine to make sure it’s shifting the way it’s supposed to. The only way to do that is to have ample room to actually drive and shift the machine. If a transmission doesn’t shift out, it could be that the differential lock got disengaged, or sometimes it’s just a bad sensor and the computer just needs to be calibrated.
• Engine: If you can, get a service history to know what’s been replaced and when. While you can easily get 10,000 hours out of an engine, it’s usually around 5,000 or 6,000 hours that you start having to replace things like rings, bearings, etc. Always check for leaks and be sure to look for signs like coolant in the water or metal in the oil.[
• Undercarriage: The tips in this excavator walkaround video will help you properly inspect the undercarriage on an excavator. The expected life of an excavator’s undercarriage will greatly vary depending on how it was used. For example, excavators working on a slope tend to produce more wear on one side than the other. Be sure to check for corrosion and pitting on roller frames and the undercarriage — corrosion over time will make the metal more brittle. Undercarriages on large highway projects or pipeline applications generally experience greater wear due to increased traveling. Note: When possible, the most accurate way to evaluate undercarriages is to measure them. You’ll need the conversion charts for each brand to convert them to percent worn.

Some additional things you can look for:

• • One telltale sign that the undercarriage is starting to get worn out is the sprocket — the thinner the teeth get, the more wear they have. I always say if they get to a point where it looks like you could shave with them, then they’re shot. And if they are, that’s usually a pretty good indicator that the rest of the link assembly needs to be replaced — not always, but usually. Note: You can put new sprockets on used rails, but you cannot run worn sprockets on new rails.
  • Be sure to measure the pins and bushings to see if they’re stretched out. Bushings have both internal and external wear. External wear can be felt by running your hand over the bushing in between the links. Internal wear can be visible by looking at the position of the track adjuster. Eventually the bushings and pins will stretch so much the track adjuster will no longer remove any slack for the rail. You should also check for any external cracking and waving. If one has a wave, that means the bottom of that link has a lot of wear. You can also count the links to see if one was removed from the link assembly in an effort to tighten the undercarriage. If someone has made it too tight, that will spell trouble in the near future.
  • Check the condition of the bushings. Typically, bushings are under considerable load at the sprocket’s six-o’clock position, and that wear will distort bushings over time. Feel if the bushings are U-shaped versus circular. If you reach up and feel past the bushing and touch or see the pin that’s in the center, they’re shot.

• Drop Box: You can expect to get 7,000 to 8,000 hours out of a drop box. If one’s up there in hours, check for any leaks and excessive noises like grinding. You’ll hear grinding or popping when a gear inside starts going bad. A new drop box can cost around $40,000 or $50,000, so it’s worth a thorough inspection.
• Axles/Differentials: These will usually last 10,000 to 12,000 hours before you start having any problems. The biggest issue you could have is external cracking, holes and leaks. With planetaries on articulated haulers, there’s a mark that states where it’s level to make sure they’re not overfilled with oil which can indicate accidental overfilling or a failing seal causing a brake leak.

As I mentioned earlier, the life of components on a used machine will vary depending on how the machine was used — so asking about its previous use and requesting a service history will give you a good starting point before you start your inspection. When you purchase a piece of Volvo Certified Used Equipment, we provide all the service details up front so you know exactly what condition the machine is in — we want you to feel confident when adding a piece of used equipment to your fleet.

If you’re in the market for a used machine, feel free to browse our complete inventory of used equipment.