Hydrostatic Drive Woes

[DeanA]

The axle tube on my AC 312H broke on the end by the differential. Does anyone have a guess as to why it may have broken (axle and gears in drive case are fine just broke the tube). Also is this tube available from anywhere, or is that drive used on any other models not quite as rare as a 312H.

[acjohn]

Even though the 300 and 400 series don't share many common parts, the hydro should be common to other tractors. At least the shuttle and manual transmissions are the same as others. If someone can confirm, post a parts wanted ad in the classifieds. Good luck.

[Kent]

Unless I'm mistaken (and I could easily be), it is a Vickers like those used in Allis HB-112/212s and Simplicity 3012-3416s...

[mrcaptainbob]

That happened to my 16 hp Wards a couple years ago. The bushing was worn in the trans gear that the axle shaft set in. It allowed the shaft to turn off center, stressing the casting. In fact, it also snapped the axle shaft at the turned down shoulder where it entered that gear. I had the axle shaft repaired and trued up and had the axle housing welded back together. It was cracked completely around right where the trans mounting flange meets the axle tube. The welding slightly distorted the mounting face, but after cleaning the face off on a lathe, it fit fine. It's been operational through lawn mowing, hauling the utility trailer, as well as the hard work of pushin' plenty of snow. The tires are fluid filled, besides. I'm pleased (and a bit surprised) that it's holding up as well as it is through all the heavy work. If you can't find the replacement parts, repairing what you have is a viable (and cheaper) alternative.