一、有负载时大量冒黑烟

                                                                   （1）进气不通畅                                                （1）检查进气道是否损坏或堵塞，予以修复

                                                                   （2） 排气背压太高                                            （2）在负载的情况下，检查并校正排气背压

                                                                   （3）在气候炎热或海拔高地区空气稀薄               （3）气候条件对柴油机有影响，空气稀薄时应减小负载