Determination of the effects of loads on some engine parameters for agricultural tractors

The objective of this study is to determine the load based engine exhaust temperature, cooling water temperature, fuel consumption and specific fuel consumption parameters and to examine the relationship between them. To this end, partial loads have been applied to three different tractor brands that are widely used in our country (Massey Ferguson 3085, New Holland TD85 and John Deere 5625) under workshop conditions at different PTO speeds (540, 540E, 750) by using an Eddy Current dynamometer. The trials have been carried out separately for each tractor and the engine parameters have been measured concurrently with the applied loads. In all trials the exhaust gas temperature has been found to be between 181.10-603.40 °C, the engine cooling water temperature between 63.20-83.40 °C, the fuel consumption between 3.15-15.68 L/h and the specific fuel consumption to be between 230.37-1112.79 g/kWh. According to the results of the research there is a distinct increase in the exhaust gas temperature and fuel consumption parameters due to the increase of PTO and there is a decrease with similar ratios in specific fuel consumption. Whereas cooling water temperature values tend to decrease very slightly due to power change. According to variance analysis results it has been determined that the PTO speed and PTO power factors and their interactions have statistically significant (P<0.01) effects on all the measured parameters. As a result of the study it has been concluded that even though the three PTO speeds have different engine operation parameters, they can be used as alternatives for each other for many PTO driven agricultural machines.