Used road-building kit pops up at auctions quite regularly, but caution is advised. Anything that is bent or worn is likely to result in you having to perform the same task several times – or else you’ll have a bumpy road.
Vibratory drum rollers put down a far greater force than simply the weight of the machines themselves, and these devices – either with single or ‘tandem’ drums – comprise the bulk of the used market. However, simple, smooth rollers for finishing work, as well as pneumatic tyre rollers, also appear on the second-hand scene from time to time.
On a drum compactor, the most important part is – as you might expect – the drum. These machines might be fitted with smooth drums, or with textured components known as ‘padfoots’. Smooth drums often suffer from dents and dimples, usually picked up by rolling over stones that have been carelessly unloaded from trailers, so check carefully.
On padfoot units, meanwhile, it is important to note the condition of the feet. A foot replacement is possible, but this should be reflected in the asking price.
Articulated
As on any machine with an articulation, the condition of the joint is most important. Check the connection for evidence that it has been regularly lubricated. If possible, operate the machine backwards and forwards to see if there is an undue amount of flexing. If there is, then you’re best avoiding that particular machine.
There’s no point expecting luxury in the operator’s station. These machines are most often found with a simple, open platform and just a ROPS canopy above the driver. Do make sure that all of the gauges work, though – anything that is obviously defective is a sign of neglect. When operating the machine, check that all of the vibratory modes work. The unit may also be fitted with dual-amplitude and high-frequency modes, so make sure these can be selected.
Air cooled
One of the unusual things about compactors is that there are still a fair few in use with old-style, air-cooled engines. These may not have as many parts to go wrong, but that doesn’t mean that they don’t require regular care and servicing, especially if they have been working in the dusty heat of the desert. Check for obvious problems, such as cracks or splits in the cylinder head, and look for excessive oil consumption. If the machine has an oil pressure gauge, check that as well.
Pneumatic tyre rollers are not used on every road-building project, yet they remain popular in the Middle East. When buying one, don’t go looking for water sipes on the tires – they are designed to be smooth and it is vital that they have the exact pressure as stated by the manufacturer.
The main benefit of these machines is that they provide a more uniform degree of compaction than steel wheel rollers. Moreover, they compact the mixture without causing hairline surface cracks known as ‘checking’.
However, these units are few and far between, so if you’re looking at one, it might be worth calling the manufacturer to check that servicing and parts are still available in your region.