Rear Bearing Install Questions
10-03-2021, 10:04 AM
#1
Rennlist Member
Thread Starter
Rear Bearing Install Questions
My driver rear wheel nut lost torque about a month back. I was due for a bearing replacement anyway so I pulled the old bearing out and replaced it with a new Porsche bearing. The hub was tight on the race and I pulled it off and re-used it. I did replace the axle stub shaft with a used spare just in case.
After torquing a new nut down with my largest impact and then finishing with a brand new torque wrench to 368, I still get a bit of play in the wheel. I confirmed yesterday that it was not the trailing arm moving. All the movement is in the hub and rotor. The play measured about 10 thousands of an inch measured at the edge of the rotor.
I have a brand new hub and stub axle coming from Germany. I wonder if I made some rookie mistake?
1.) Is the bearing directional? Can they be put in backwards? The old one doesn't appear to differ in either direction and there were no real markings.
2.) I notice the stub shaft looks like it partially installs in to the inner bearing race. Is torquing the axle nut enough to seat this or is there an additional press step I need. Does the axle stub need to press in to the race somehow after the hub is pressed in?
3.) Is it possible that the bearing itself was bad? The inner race felt like it had play but I assumed torquing the axle nut would have resolved that.
4.) I wonder if there's a way to tell if the play is in the hub versus if it's in the trailing arm (outer race)?
I had to use a bearing press to get the hub re-installed. It seems quite tight. The bearing itself slid in to the trailing arm with no effort, but I had froze the bearing and heated the arm to 120c per Porsche manual. It then seized in place. Maybe it needed more of a struggle?
After torquing a new nut down with my largest impact and then finishing with a brand new torque wrench to 368, I still get a bit of play in the wheel. I confirmed yesterday that it was not the trailing arm moving. All the movement is in the hub and rotor. The play measured about 10 thousands of an inch measured at the edge of the rotor.
I have a brand new hub and stub axle coming from Germany. I wonder if I made some rookie mistake?
1.) Is the bearing directional? Can they be put in backwards? The old one doesn't appear to differ in either direction and there were no real markings.
2.) I notice the stub shaft looks like it partially installs in to the inner bearing race. Is torquing the axle nut enough to seat this or is there an additional press step I need. Does the axle stub need to press in to the race somehow after the hub is pressed in?
3.) Is it possible that the bearing itself was bad? The inner race felt like it had play but I assumed torquing the axle nut would have resolved that.
4.) I wonder if there's a way to tell if the play is in the hub versus if it's in the trailing arm (outer race)?
I had to use a bearing press to get the hub re-installed. It seems quite tight. The bearing itself slid in to the trailing arm with no effort, but I had froze the bearing and heated the arm to 120c per Porsche manual. It then seized in place. Maybe it needed more of a struggle?
10-08-2021, 11:28 PM
#4
Rennlist Member
Thread Starter
Interesting, did you have a nut come loose as well? I've heard that can damage the hub. That is what I expect is goofed up on mine but I won't really know until November when I get the new parts.