拖拉机修理经验大家谈□任双荣张清１一台东方红—７５型拖拉机，供油提前角较小，导致排气管冒黑烟，有时还冒火星。调整供油提前角后，发动机却启动不着了。原来机手调整供油提前角时，将花键连接盘的２个螺钉拆下，再次安装时，其中一只拧不上（没有对正记号），就采用... Tractor repair experience We talk □ Ren Shuangrong Zhang Qing 1 an Oriental Red -75 tractor, fuel supply advance angle is smaller, resulting in exhaust pipe black smoke, and sometimes take the Mars. After adjusting the fuel supply advance angle, the engine can not start. When the original hand to adjust the fuel supply advance angle, the spline connection plate 2 screws removed, when installed again, one of them screwed on (not correct), the use of ...