An article by "L J Jacobson"
Ok, having recently experienced some rear wheel bearing problems with my Bird, and having swapped out the MK VIII half shafts. A couple potential pit falls have manifested themselves:
To whit, the locking nuts for the half shafts are NOT REUSEABLE!! see pic below where I have opened up one of the nuts to satisfy my curiosity. the crimp on shell exerts pressure on several layers of threaded thin nutz, acting as multiple jamb nuts...There's also a free washer, underneath, which in turn exerts pressure on some crennalated parts of the inside collar against thehalf shafts slight flare beyond the splines.( Not shown)
The shell half removed,
The nuts are about $9.00 each, and can only be used once.. the tork spec is 251 ft/lbs, and the nut requires a 36mm socket. The tork wrench and socket for this app. isnt available in every ones tool box, so renting or borrowing from autozone are vaiable options, that is unless youre buddies with a heavy equiptment repair specialist.
If you experience a subtle chassis vibration at speed, or a loosey goosey feeling in the rear end, its probably the rear wheel bearings going out due to either age , or those blasted nuts backing out...... here is a pic of the MK VII half shafts (orange, a manly color).
The center shaft is 1/8 inch thicker than the MN-12 shafts.... The splines are the same, so there is only a tiny bit of difference in the robustness of them , but I will take what I can get with my tork...
Heres a pic of a spindle that got chewedup by a failed bearing;
Notice how the outer bearing race siezed, and scored the outer surface of the spindle.... thats a press on fit, so imagine the heat/ rolling resistance generated! I ended up haveing to buy a junkyard knuckle/spindle assy , and put the new bearing in that as well as remount the brakepads , etc.heres apic of the replacement knuckle(used)
with the new bearing allready pressed in.