top of page
  • Writer's pictureRALPH COPE

Thinking about buying a Used Excavator? Here are FOUR Things to Look for....




Excavators are big-ticket assets, so you want to do your homework before cutting that check. Here are four things you need to inspect.


#1 Undercarriage


This is the bottom substructure of the machine and the point of impact with the ground. You firstly want to check the sprockets. The more rounded or smooth the teeth of the sprockets the better. If they are razor-sharp like a knife, it means that they have been exposed to considerable wear and will need to be replaced. Having said this, it is not costly to replace a sprocket. Secondly, you have the top and bottom rollers. Here you want them to be as rounded as possible. Also, listen to hear if they make a loud squeaky noise when the tracks are moving. There should be no play in the rollers – if there is, the bearings are shot. Like the sprocket, rollers are not expensive to replace. Thirdly, you want to closely inspect the chains (also referred to as links). Again they should be as rounded as possible. If they have been worn into the shape of a C, it means that the tracks are older and have a limited lifespan in front of them. These flat spots in the links are caused by sharpening in the sprockets. Fourthly you want to check the grousers (also referred to as shoes). You want them to be tight on the tracks with a limited amount of play. Finally, you need to look at the track adjuster. Again, you must listen for noise when the machine is moving. Also, if the adjuster is extended far out forward, it means that the chains are stretched and may soon need to be replaced which is going to cost you money.



#2 Engine


Now you need to fire up the engine and go up on top to inspect the engine. The first thing you want to look at is the exhaust to ensure that there is not too much smoke coming out. Secondly, on the engine, you want to make sure there are no leaks. You want to open up the oil cap and look for blow-by. You will know there is blow-by if there is oil around the cap, when oil is flying out the opening, or when you lift out the dipstick and oil are bubbling out.



#3 Final Drives


You will need to drain the oil on the final drives and check for filings. You also need to check to see if the oil is new. New oil can sometimes be problematic and an indication that the seller is trying to hide a defect in the final drive. The bottom line is that you do not want to oil to be too clean or too dirty – both these situations should sound warning bells. Once the oil has been drained, remove the cover and check the gears for wear. Again, you want to ensure that the teeth on the gears are not too sharp.



#4 Ring Gear/Slewing Ring


If you’ve ever sat in the cab of an excavator, grabbed a bucket of dirt, spun a circle, and sent that load sailing off to a perfectly placed pile, you probably already know that under your feet a slewing ring helped make that job possible, but since that slewing ring is buried deep in your machine and hidden from view, we often forget about it. Replacing this part is not expensive, but it is a really difficult job because you need to separate the undercarriage from the rest of the machine. To test if there is play in the slewing ring, slew the bucket to the side of the machine, set the bucket down, and lift up the tracks. If there is movement in the ring gear, it may need to be replaced


Comments


bottom of page