Model 20: Lathe Turning Differential Housing

I've read about truing the mating surfaces of the differential housing for straightness and to reduce leaks. However, I can't picture how this is done. Is it something a decent machine shop could do on a standard lathe, or does it take special equipment?

Phil

G,day Phill. Unless the faces are badly buckled or cracked I would not bother with truing them . I have seen flanges that were so thin as to not take a cut. Locktite 515 gasket sealant will take up the slack here unless badly buckled. Hupmobile obviously had no quality control inspection and used everything even if the worst components were sent to export. Be sure there are no cracks or striped threads where the torque tube is connected to the axle housing. Running a flame from your torch will bring out the oil and show the cracks if present. Individualy the housings can be turned in a centre lathe by griping the axle bearing extension in the chuck and running a pipe centre into the carrier bearing recess in the other end, then mount a three point steady to the axle housing tube as close to the work as possible to avoid chatter. If you think the housings might be bent make up two wooden plugs to fit at the wheel bearing ends and with a hole in the accurately found centre of each plug pass a string line tightly through from end to end. The string should pass through the exact centre of the carrier bearings. The Hyatt flex bearings allowed for some misalignment here but others do not. Its all just a matter of one thing at a time. Max Burke Nulkaba 2325 Australia