Lotus Elan

Rear Hub Won't Turn

PostPost by: Tmac897 » Mon May 25, 2020 9:02 pm

This from the "Don't We Really Feel Stupid Now" file:

I installed one of the rear hubs, and I managed to get it on too tight. Now the hub is rubbing against the bearing circlip, and/or the bearing carrier, and it won't turn without some effort. Free spinning it's not.

I followed the process pretty carefully. I tapered the inner end of the keyway to relieve the axle stress point. I shortened the key so that it was flush with the outer end of the keyway, and such that it sat perflectly flat in the keyway. I put a thin coating of Loctite Blue on the axle, and heated the hub to a perfect medium well done, and I torqued the bolt on to 100#, or thereabouts (more on that later...)

Obviously I have to remove the hub again (Oh joy of joys!). But what could I have done to produce this result, and more importantly, how can I avoid it again, once the shame wears off, and I can look my toolbox in the lid again?

One possible explanation is that I went beyond 100#. My torque wrench was set properly, but it didn't click. I stopped when logic demanded it, but when I tried to back off the bolt, the wrench clicked like it was its job. So I'm pretty sure I went beyond 100#, but like 105-110, not 125-150. While I'm not totally dismissing it, I doubt a few extra pounds of torque produced this outcome.

Any ideas?
Tony
1967 Elan S3 SE
Northeast US
Tmac897
Second Gear
Second Gear
 
Posts: 96
Joined: 01 Aug 2019
Location: New Jersey, USA

PostPost by: snowyelan » Mon May 25, 2020 11:12 pm

I've never heard of heating the hub before assembly, only as a method of removal. I think the 100ftlbs is a bit low from what I've read so I don't think that the bit over you applied was the reason. Best guess is the heat increased the bore size and allowed the hub to be installed too far inboard.
Scott
45/9011
Hawkestone, On, Ca
snowyelan
Third Gear
Third Gear
 
Posts: 228
Joined: 14 Sep 2003
Location: Hawkestone, Ontario, Canada

PostPost by: h20hamelan » Mon May 25, 2020 11:23 pm

You could reverse torque, and see what the break-away force is. If your torque wrench has a reverse feature.
The inner bearing facing the correct way?
I would have thought, cooling the hub. If it were tight, as heat to the bearing would/will destroy her.
W. Kootenays B.C. Canada
Born, and brought home from the hospital (no seat belt (wtf)) in a baby!
Find out where the limits are, and start from there
User avatar
h20hamelan
Third Gear
Third Gear
 
Posts: 483
Joined: 25 Sep 2010

PostPost by: Tmac897 » Mon May 25, 2020 11:31 pm

Reread the DBE manual, and you are correct - no heating on the reinstall. There are a couple of sentences about heating the hub in the reinstall section, but that’s info about the way Loctite Blue reacts when heated to 400 degrees But that’s all about the subsequent disassembly for “the next time.” Poop.

I read that section 5 times. I guess I was nervous about doing this right, and got it wrong. Should be fun trying to pull that hub off now.

As always, thanks for your help.
Tony
1967 Elan S3 SE
Northeast US
Tmac897
Second Gear
Second Gear
 
Posts: 96
Joined: 01 Aug 2019
Location: New Jersey, USA

PostPost by: h20hamelan » Tue May 26, 2020 12:40 am

Bet the hub comes off easy, and a minute with a file. New key, and your off
W. Kootenays B.C. Canada
Born, and brought home from the hospital (no seat belt (wtf)) in a baby!
Find out where the limits are, and start from there
User avatar
h20hamelan
Third Gear
Third Gear
 
Posts: 483
Joined: 25 Sep 2010

PostPost by: Tmac897 » Tue May 26, 2020 1:21 am

h20hamelan wrote:Bet the hub comes off easy, and a minute with a file. New key, and your off


Hope you’re right. Not sure where the file comes in. But you think a new key will b required?
Tony
1967 Elan S3 SE
Northeast US
Tmac897
Second Gear
Second Gear
 
Posts: 96
Joined: 01 Aug 2019
Location: New Jersey, USA

PostPost by: bitsobrits » Tue May 26, 2020 1:36 am

Hmm...

Getting that hub off will likely be a real bear. Sounds like you have effectively shrunk fit the hub to the stub shaft, which may have done permanent damage to the hub. You will want to measure it very carefully once it's off. The amount of heat required to sufficiently expand the hub again will be difficult to accomplish now that it is installed and may well cook the outer bearing seals. And you will of course need a stout puller arrangement. But mostly heat.

Yikes.
Steve

Elan S1 1963-Bourne bodied
Elan S3 1967 FHC pre airflow

Formerly:
Elan S1 1964
Elan S3 1966 FHC pre airflow
Elan S3 1967 FHC airflow
Elan S4 1969 FHC
Europa S2 1970
Esprit S2 1979
bitsobrits
Third Gear
Third Gear
 
Posts: 232
Joined: 27 Apr 2011
Location: Omaha, NE area

PostPost by: bitsobrits » Tue May 26, 2020 1:50 am

Just checked out my own project (S3 w/knock on wheels) and based on the shape of the rear of the that hub it looks nigh on impossible for the hub to contact the snap ring, even if it was somehow installed too far on the shaft.

How much clearance do you have from the back of the hub to the alloy housing?

Is this a bolt on or knock on hub?

Once the retaining nut is removed, can you post a photo to show how far the shaft is from the edge of the hub?

Also a photo of the hub to alloy housing clearance would be helpful.

Just remember there are enough very knowledgeable people on this forum to help you out of this bind and back on the path to a rolling car. It's just another learning experience. I've had many :oops:
Steve

Elan S1 1963-Bourne bodied
Elan S3 1967 FHC pre airflow

Formerly:
Elan S1 1964
Elan S3 1966 FHC pre airflow
Elan S3 1967 FHC airflow
Elan S4 1969 FHC
Europa S2 1970
Esprit S2 1979
bitsobrits
Third Gear
Third Gear
 
Posts: 232
Joined: 27 Apr 2011
Location: Omaha, NE area

PostPost by: Tmac897 » Tue May 26, 2020 2:09 am

DE79474D-5F5F-4A12-A1BD-D4C7FDBA3534.jpeg and
Front view
2F96E958-7E4D-4EAD-97EA-DE3C34142696.jpeg and
Clearance to carrier



As you can see, this is a bolt on hub.
Tony
1967 Elan S3 SE
Northeast US
Tmac897
Second Gear
Second Gear
 
Posts: 96
Joined: 01 Aug 2019
Location: New Jersey, USA

PostPost by: alan.barker » Tue May 26, 2020 5:01 am

I think you have assembled the inner bearing on the drive shaft the wrong way round.
Alan
alan.barker
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2300
Joined: 06 Dec 2008
Location: BRITTANY FRANCE

PostPost by: MarkDa » Tue May 26, 2020 7:36 am

Yes installing the inner bearing the wrong way round would mean the axle protrusion would be reduced by a few mm which would be quite enough to draw the hub back against the carrier.
Heating the hub would also allow it to go further back onto the shaft.
You can easily check this by just looking - the inner and outer races should be flush. I doubt whether the dust shield would fit if bearing reversed.
Heat shrinking the hub onto the shaft does mean that it's going to be a "bit more difficult" to remove I'm afraid.
The torque used is about right for cold fitting - putting it on a hot hub will certainly make for a "secure" installation.
The saving grace is that you have a bolt on hub so you can get a heavy duty puller onto it for removal.
You may need heat and that may damage the bearing seal but that's not a big deal in scheme of things.
If there wasn't a problem prior to dismantling the you should be able to get it right again.
MarkDa
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1141
Joined: 15 Apr 2017
Location: Stroud

PostPost by: davidj » Tue May 26, 2020 8:30 am

Correct me if I am wrong, I don't have my manuals to hand and working from memory, but this is a bolt on hub/bearing carrier and therefore an earlier one. Consequently both bearings are the same and cannot be fitted the wrong way round. The later assembly had different size bearings. However a later carrier may have been used with earlier hubs?

I think the problem would be caused by heating the rear hub. Good luck getting it off.
davidj
Third Gear
Third Gear
 
Posts: 328
Joined: 09 Apr 2008

PostPost by: rgh0 » Tue May 26, 2020 8:34 am

I am sure the hub can be removed with the right puller and a little heat and a lot of patience :lol: . The problem may be that the taper has been permanently distorted on the hub. The end of the axle appears parallel with the end of the hub when it should be some what below. I suspect with the hot hub the 100 ft lbs pulled it up until the washer bottomed on the end of the shaft as well as the hub. I don't have the manual in front of me but I think the cold tightening toque specified for the hub nut is around 180 or 200 ft-lb

I had a similar problem when at a race meeting many years ago when a hub spun on the shaft. Trying to tighten it up failed to lock it in place as it hit the bearing before the now worn taper seated. I temporarily fixed it by filing metal off the back of the hub and using a spacer washer with a large hole filed in it to avoid bottoming out the washer under the hub nut on the shaft. This worked for the meeting but the spun hub needed replacement and the one on the other side was showing signs of distortion on the hub taper which said it was not going to last much long either. The bolt on hubs are less rigid than the KO hubs and the taper appears to wear / distort into an hour glass shape over the years especially with hard use with sticky tyres.

Bolt on hubs were used on later standard cars as well that used the Issue 18 carriers and shafts

cheers
Rohan
User avatar
rgh0
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 7488
Joined: 22 Sep 2003
Location: Melbourne, Australia

PostPost by: Tmac897 » Tue May 26, 2020 10:31 am

I had the bearings pressed in at a machine shop. I originally had two different sized bearings, but the races were too small for the larger bearing. I reordered from DBE, and those bearings were the same size, I'm pretty sure. So while that might not be what you mean, I don't think the inner and outer are reversed. If I'm wrong, please don't hesitate to put me straight.

That having been said, he left out the dust shield, and the axle did look like it was in a little different position relative to the other side, i.e., the axle did not protrude quite as far out of the carrier. So there may have been some error in the bearing installation. But I seem to be speculating.

In any case, the hub has to come off, so I'll start there. Patience is not generally in my vocabulary, but I've got a pretty well developed inventory of swear words at the ready.
Tony
1967 Elan S3 SE
Northeast US
Tmac897
Second Gear
Second Gear
 
Posts: 96
Joined: 01 Aug 2019
Location: New Jersey, USA

PostPost by: Tmac897 » Tue May 26, 2020 10:41 am

rgh0 wrote:I am sure the hub can be removed with the right puller and a little heat and a lot of patience :lol: . The problem may be that the taper has been permanently distorted on the hub. The end of the axle appears parallel with the end of the hub when it should be some what below. I suspect with the hot hub the 100 ft lbs pulled it up until the washer bottomed on the end of the shaft as well as the hub. I don't have the manual in front of me but I think the cold tightening toque specified for the hub nut is around 180 or 200 ft-lb

cheers
Rohan


There is actually about .25" between the end of the axle and the end of the hub. Tried to get the best pic I could, but it was a tough angle with the lighting in the garage. Also, my workshop manual said 100#.

Thanks,
Toy
Tony
1967 Elan S3 SE
Northeast US
Tmac897
Second Gear
Second Gear
 
Posts: 96
Joined: 01 Aug 2019
Location: New Jersey, USA
Next

Total Online:

Users browsing this forum: No registered users and 16 guests