Editor's Comment: Fuel concerns

If you live outside Europe, Japan or the US and are planning on buying a used excavator over the next few years, beware! If you buy a machine with an Interim Tier 4 or Stage IIIB-compliant engine and you don't have access to ultra low sulphur diesel, you may quickly end up with a dead machine on your hands.
New laws on diesel engine emissions were introduced in Europe and the US at the start of the year. Their aim is to cut the amount of black soot coming out of off-highway machines' exhaust pipes, and thereby improve air quality. Previous emission control limits have been met with various technologies focussed on the engine, but in order to meet the latest requirements, manufacturers have added aftertreatment devices in the exhaust system.
In order for these to work, engines must be fuelled with ultra low sulphur diesel (15 parts per million of sulphur or less). More than this and the aftertreatment systems will be overwhelmed with soot particles, the backpressure on the engine will increase and it will quickly overheat, perhaps causing permanent damage.
Manufacturers and their dealers can control where machines are sold when they're new, so there isn't too much risk of an Interim Tier 4/Stage IIIB machine initially finding its way into a country where the right fuel is unavailable. However, the used equipment market is a global one, and after a few years of work with their first owner in Europe or the US, popular machines like excavators can find themselves anywhere in the world.
Manufacturers say that they could potentially provide aftermarket kits to 'de-tier' engines - essentially remove the aftertreatment components that are sensitive to dirtier fuel. However, while this is technically feasible, the legislative implications are far from clear.
Although developed world countries do not have emissions standards as high as Interim Tier 4 and Stage IIIB, many do have emissions laws of some kind. The legislative question is, if an engine is de-tiered, would it then have to be re-certified to prove that it could meet a different emissions law?
It's a question that no-one seems to know the answer to at the moment. That's fine, as it's not a pressing issue right now - Interim Tier 4/Stage IIIB machines are only just becoming available from manufacturers, so it will be a few years until they work their way into the used equipment market.
But it is an issue that will have to be addressed sooner or later. In a few years when markets are back to normal health and every machine over about 5 tonnes is Interim Tier 4/Stage IIIB emissions compliant, there could be around 150000 construction machines per year coming onto the used equipment market fitted with exhaust aftertreatment. Many of these will stay in the markets they were originally built for, but many will not.