22-11-2020, 06:16 PM (This post was last modified: 22-11-2020, 06:54 PM by Howard Wright.)
Hi All
Everything was going really well with my axle build until I tightened up the flange bolts for the final time. Whilst the pinion moved the crown wheel quite freely during the meshing process I hadn’t checked the planet wheels. Tightening up the flange bolts caused the differential action to stiffen up. The pinion still moves the crown wheel quite freely but the planet wheels are almost locked.
After some head scratching I’ve discovered that the flange of the axle tube is bent at one bolt position and I think this might be causing the problem. It is about 1/16” out of line.
Any ideas on how to flatten the flange? Should I use heat or just cold bend against a former?
The bent flange is unlikely to lock the diff.
Yes you can knock the flange back into shape if you have a suitable flat heavy block and a suitable hammer.
As the outer hubs get lapped and pulled up over the years the half shafts move outboard until the halfshaft spur gear locks up against the outside of the diff carrier. ( It is often self curing at the expense of filling the axle with metal swarf )
The cure is either new half shafts / New Hubs / turning a bit of the spur gear off or facing a little bit of the diff carrier.
If you have another outer hub that is the first thing to try.
The axle tubes are definitely straight as I’ve just shortened them and was meticulous in getting them so and to the right length (to within 1/32”). The half shaft/ hub clearance is also well within tolerance. In fact I haven’t fitted the inner hub yet but used the outer as a means of trying to turn the half shaft.
The only other possibility is that the new bushes in the diff carrier are too tight but with the carrier and half shafts assembled they turn freely. I line reamed the bushes in the lathe so I don’t think they are out of line.
I’ll try straightening the flange using an old banjo I have as a restraint to pull in the flange at the distorted point.
If I had that problem I would use my hydraulic press, because it has enough thrust to flatten the face, but can be used gently enough to avoid going too far.
I don’t have a press but I managed to push the flange dent out by tightening the rest of the bolts against an old banjo with a nut under the damaged section (I did help it a little with a hammer .)
.)