Its good that he has started out working with the power delivery on his dozer build first. By mounting the pumps to the engine he now has some idea of the dimensions required to mount the engine . A 0.001-" to +0.005 for the bore of the mounting flanges would have helped him but those things happen,
In video#2 though that thick tooth is going to come back and bite him unless like he said he is only going to use every other tooth, this would require his sprockets to have an even number of holes drilled for the teeth and the double pitched chain will have to have an even number of rollers. the way all tracked machines are built though is to be odd even. this insures even wear on the sprockets. It also looked like in the video that he turned the OD of the sprocket. down more than he should have. the teeth on sprockets are as tall or taller than the roller diameters, The best way he could have machined off the weld effected area on the sprocket would have been to anneal or normalize the weld on the sprocket before machining.by heating to cherry red and allowing it to slowly cool
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