(1) The electric starter small four-wheel tractor currently used in production, most of which is equipped with a permanent magnet type AC constant voltage generator equipped with a silicon rectifier, and the output direct current charges the battery and supplies the light. If the configured rectifier is damaged, and no accessory can be found at a time, the XF-250 motorcycle rectifier can be used instead. (2) The tank underpad of a single-cylinder diesel engine is difficult to remove during the replacement period. A quick and easy removal method is now provided: find a hammer and tap on the old water tank paddles one by one, then the old water tank pad can come off. Then use a scrap steel blade or waste oil to scrape the outside of the piston. (3) The operator of a Taishan-30 tractor reported that the cold start of the diesel engine was relatively difficult. Hot car starts normally. The pilot thinks that the battery capacity is insufficient. After inspection by the author, it was found that the battery holder was modified into the driver's cab after the driver's hand, and the ground wire was connected to the battery rack. Because the grounding iron circuit was connected to the body through the upper platen and the pull rod, two of the pressure plate and the pull rod The point contacts are formed at the ends, causing a large voltage drop, thereby causing spurious battery capacity deficiency. The author will change the ground wire to directly connect with the car body, and the cold car starts to return to normal.