Biodiesel Testing

Biodiesel New Zealand has been working with its customers to learn more about optimum blends for local New Zealand conditions.

The vehicles listed below were driven through the 2006 winter on blended Biodiesel New Zealand fuel. During the warmer months we supplied a B90 blend (90% Biodiesel 10% petroleum diesel). As the temperatures dropped, we graduated the blend to B60 and by September it was back up to B70.

Many owners reported an increase in mid-range responsiveness. All said their vehicles performed as well on Biodiesel as they had on petroleum diesel and all noticed a significant reduction in exhaust emissions.

On the coldest days (when overnight temperatures dropped below 0 degrees) drivers whose vehicles were left outside reported a miss in the first 10 seconds after starting. This disappears, however, if the vehicle is allowed to warm up for a few moments. This condition was only reported following the coldest nights and none of the test vehicles failed to start or let their drivers down.

Shown at right above are the injector pintles of a Mazda Bounty utility run by Diesel Pumps in Christchurch. This engine’s injectors had been cleaned 50 000km earlier. Since then, the first 35,000km used petroleum diesel and the most recent 15,000km on Biodiesel New Zealand product. The pintle on the right has been cleaned and the others are as they were at the end of the 50,000km. The only build-up is a slight amount of carbon, less than the technicians expected to find if the vehicle had been running petroleum diesel the entire 50,000km.

The pintle seats (below right) are also remarkably clean of build-up, cleaner than would have been expected if the vehicle had run only on petroleum diesel.

If the Biodiesel used had not been up to standard, you would find a number of build-ups and deposits in this area. These include white nodes on the injectors caused by the catalyst not being removed from the Biodiesel and lumpy build-ups in the seats which can range from grey to black. Excessive wear in the pintle seats or pitting on the pintles themselves this can also be caused by the fuel being too acidic.

Please note that the tested vehicles were running on Biodiesel New Zealand’s vegetable oil-based Biodiesel, not tallow biodiesel.

Vehicles used in Biodiesel Trials in 2006