The invention relates to a
casting method for an aluminum
alloy engine shell. The
casting method sequentially includes the following steps that firstly, red
copper pipes are manufactured to be in a shape the same with that of shell oil ways, and the red
copper pipes are sealed after being filled with precoated sand; secondly, cores are manufactured; thirdly, the red
copper pipes and the cores arecombined and fixed; fourthly, the cores are subjected to pulp dipping and then sand pouring, then pulp dipping is conducted again and sand pouring is conducted again, the operation is conducted repeatedly by multiple
layers, inner die shells are obtained, dewaxing is conducted after the inner die shell is subjected to
air drying, and high-temperature
roasting sizing is conducted; fifthly, sand molds are manufactured in sand boxes, cavities coincide with the outer wall of the engine shell in shape, and
casting systems are arranged in the sand molds; sixthly, the inner die shells are put into the cavities of the sand molds, then mold assembling is conducted; seventhly, aluminum
alloy liquid is injected into the cavities till
mold filling is completed; eighthly, after cooling forming, the engine shell is obtained, spare parts are removed, and the precoated sand in all the red copper pipes is removed; ninth, the shell engine is immersed in a dilute
nitric acid solution, and the red copperpipes are corroded and form oil ways. By means of the casting method, the manufacturing cost is low, consumption of raw materials is low, the product quality is good, manufactured hole ways are smoothand reliable, and the yield is high.