Simple diesel engine generators in general are noisy and pollute air. It is urgently needed to find alternative fuels applicable for new as well as old engines without structural modifications and along with keeping the environment clean. Diesel-alcohol blends could be such alternatives fuels. For that purpose, in this study tests were carried out using diesel fuel first then, were carried out using three of n-butanol/diesel blends on volume bases with n-butanol concentrations of 5, 10 and 15%, identified as nBu5, nBu10 and nBu15. The engine under study is a single cylinder, four stroke, air cooled diesel engine generator and the tests have been carried out at a fixed 3000 rpm and five different load conditions without any hardware modifications. Total noise, engine block vibration, NOx, HC, CO, BSFC, BTE and EGT have been observed of diesel and n-butanol/diesel blends. The following conclusions can be drawn with nbutanol/ diesel fuel blends against diesel fuel; (i) According to engine performance test results; a little higher specific fuel consumption was observed with corresponding slight increase of brake thermal efficiency and little lower exhaust gas temperatures. (ii) According to engine emission test results; the NOx was slightly reduced, this reduction being higher the higher the percentage of butanol in the blend. The CO emissions were reduced, on the contrary, HC emissions were increased, this increase being higher the higher the percentage of butanol in the blend. According to engine vibration and noise test results; Noise and vibration characteristics are somewhat better especially at lesser loads.