Sprockets play an important role in heavy equipment, without them of course the machines wouldn’t move! We’ve got a few tips to ensure when ordering sprockets you get what you need. Often it is not black and white with so many different machines and variables on OEM parts that the parts advisors themselves may not be aware of an unexpected scenario.
When replacing steel tracks it’s typically a good idea to replace sprockets at the same time as the chains. This however, isn’t necessarily the case with mini excavators on rubber tracks. A good rule of thumb with rubber track diggers is to replace sprockets on every other rubber change. Considering this could be over 1,500 hours, it is recommended to do an inspection just to head off any premature problems with track failure. A worn sprocket not engaging properly can tear a lug out of a track and you’ll certainly have to replace the rubber track.
Mini Excavator Sprockets
There is a significant key difference in sprockets when dealing with rubber tracked mini excavators 3 tonne and above. The excavator (using a 300mm wide rubber track) will have been manufactured with two different guide widths; what’s called by industry standards as ‘wide’ and ‘narrow’ gauge. The sprocket on a rubber track excavator will be designed to correlate with this gauge. There is a quick method to work out whether your rubber track is a wide or narrow gauge. The narrow guide can be determined by laying two fingers into the tracks guides. The wide guide can be determined by laying three fingers into the guides.
Skidsteer Loader Sprockets
Now let’s look at skidsteer loaders such as ASV, Bobcat, Cat 247, or Kubota SVL75’s. Bobcat compact skidsteer loaders, in particular, utilize a dished-styled sprocket. Different models can use a varying depth bowl with a serial number breakdown. It is wise to check this out carefully on your machine because you cannot rely on the parts person to use your serial number only to determine this. Reason being, some machines may actually have two different final drives/track motors on them requiring two different sprockets. To determine the bowl depth, simply set the sprocket on the ground and measure from the ground to the top of the teeth. It may be a little more difficult to do while installed, but you generally only have to be close as there are only about two sizes. In some cases, a spacer may be utilized to make the final fit.
With Takeuchi track loader machines, specifically the TL140 and Tl150, you will need to know the inside opening diameter where the sprocket fits over the track motor. There are two dimensional options: 200mm or 242mm.
You should also advise the parts person on the number of teeth and the number of bolt holes that your sprocket has. This will enable them to recommend a product that will fit. Many sprockets will have more bolt holes than your machines require but keep in mind that manufactures try and cover as many machines as they can with one part. This is prevalent across the industry and not just rubber tracked diggers.