BN1 hub nuts - loosening while driving?

[PSJ]

Hello Healey friends! This is a kind-of-embarrassing issue, but I will forge on, regardless. The issue is regarding wire-wheel hub nuts (the nuts holding the splined wire wheel hub and axle to the hub/bearing carrier) appearing to loosen themselves. Please excuse any improper terminology.

Background
Recently I helped my Dad with his 1953 BN1, converting his pumpkin from a 4.11 to a 3.9. The rear end is NOT the original, but a later type (helical?). I helped him get the pumpkin out, and after he had the new R & P installed, put it back in. He performed the finishing touches, like re-installing the axles, putting the drums and wheels back on, etc.
After it was all together, he invited me to captain it for a test drive. Everything seemed fine, until about 5 miles in, I began to perceive a problem - untoward movement of some type in the rear of the car. When we examined the car, it appeared that the left rear hub nuts had not been thoroughly tightened, and that the wire wheel hub was experiencing movement relative to the hub carrier. The hub nuts had been damaged, but the studs appeared OK. My Dad tightened the nuts and ordered new ones, thinking that the problem had been diagnosed and temporarily addressed.
Later, my Dad took the car for a drive. The new nuts had not been received, so the car still had the old (damaged) nuts. He made it a few miles, but again experienced similar issues. Upon examination, nuts had again loosened, two studs had broken off and others were damaged.

Hypothesis (please throw rocks at it!)
The problem has it's root cause in the original assembly, where the nuts were not appropriately tightened. Afterwards, the damaged nuts were not in appropriate condition to take further stress, thus the second failure and damage. (Note: the bearing carrier was not loosened or removed during the work; nor does it appear to have been damaged; nor were the axles completely removed from the axle housing when we switched the R & P). With this assumption, correct installation of new studs and nuts should cure this issue.

My request of you!
Could you please consider and let me know your thoughts? I can't think of any other root cause diagnosis, as the hub carrier was not touched during the work. Could the new R & P be putting stress on one axle? That seems unlikely.

Last item: Regarding the removal of the hub carrier for the installation of new studs: do you have any specific comments or direction? I know that, on some MG's, the torque value of the main hub carrier/bearing retaining nut is critical. My Dad has a service manual for the Healey, so I was just going to follow that. (Hmmm . . . it might not have the right instructions for the later rear axle - I'll have to check).

So geez! Sorry for such a long message; and thanks in advance for your help.

Phil

 

[abarth69]

Phil

Make sure you are using the correct locknuts they are special nuts.Also make sure the HUB EXTENSION holes are not oval.

Cheers

Mark

 

[tahoe healey]

The nuts have one or two slits in the that allow them to compress tightly. I have always been told not to reuse them but I have been successful one reuse but would not go for two. When I reused them, I slipped a knife in the slit to stretch it out before torquing. I believe it is 55 Lbs and cross rotate as you torque.
Did you remove the brake drum and the Phillips screw?

 

[Keoke]

MY guess is you have worn studs and/or hub nuts---Keoke

 

[bob hughes]

I doubt that the new R&P has caused the problem, that is a regular upgrade for economy, I am with Keoky, It's only on one side.


Bob

 

[PSJ]

Thanks guys - you are terrific! I will proceed, then, with helping my dad replace the studs and nuts. I'll let you know if we have any more excitement! I don't like the "wheels falling off" thing!

Phil

 

[Patrick67BJ8]

The nuts have one or two slits in the that allow them to compress tightly. I have always been told not to reuse them but I have been successful one reuse but would not go for two. When I reused them, I slipped a knife in the slit to stretch it out before torquing. I believe it is 55 Lbs and cross rotate as you torque.
Did you remove the brake drum and the Phillips screw?

I've reused mine <span style="text-decoration: underline">several </span>times and never had a problem. I do carefully "seat" the parts going back together after doing a brake job and/or replacing seals. I do not use thread lockers. I may swithch to Chevy bolts at about a buck each when I finish up the frame up restoration.
Patrick

 

[red57]

I agree with Patrick67BJ8. I have re-used them lots of times, and he is right about carefully 'seating' and making sure there are no burrs/debris to prevent a full mate-up.

My guess is that there may have been a burr or a small bit of grit preventing full seating that allowed it to loosten in use. With new studs and clean surfaces/seating I'll bet you will have no more problems.

Remember, these are really "lug nuts", just holding the wire wheel 'adapter' on instead of a wheel. We don't replace lug nuts when we change a tire on any other car....unless they are damaged somehow.

BTW these are 7/16 studs so torque should be about 65#.

Good luck,
Dave

 

[PSJ]

Excellent. Thanks guys!

Phil

 

[PSJ]

Now I'm back! With another question! And a few exclamation marks!!! I'm grateful for the advice and assistance I've received from you, and would like to ask your assistance once again.

The further we delved into the hub and axle housing, the worse things looked. The large, thin nut that holds the hub onto the axle housing was damaged, as were the threads on the axle housing and the "shim" that goes under the nut. The good news is that we were able to source a Whitworth thread file and touch up the threads on the axle housing. A new nut is now installed, along with new bearings, new studs, and a new shim. We're excited to be making progress, although I'm sorry for my dad that he's missed this entire driving season.

So here's my question: What is the desired torque setting for the (big, shallow) nut that holds the hub on the axle housing? Or, is there instead a different measurement that would indicate proper installation? I was incorrect in my assumption that my Dad had a manual . . . I'll have to source one!

Thanks in advance for your help!

Phil

 

[bob hughes]

The boys in the Healey garage use a rattle gun - no torque

Me - I used a bloody big box spanner with an inner mandril to fit inside the axle housing - helps keep the box spanner in place - and then a 2-3 foot lever to get it up tight. I have since acquired a 3/4 inch drive bar to drive the box, but it has not yet been used in anger yet.

The good book says 140 lb.ft torque



Bob

 

[PSJ]

Bob! Thanks very much for your help. 140 lb.ft it will be!

Phil

 

[Legal Bill]

What does the manual say?

Be very careful whaen you tighten that nut. Most sockets are a bit champhered at the end and the nut may be too thin to properly engage the flats of the socket. I think there was a factory tool for this application and we used to make our own by grinding down the socket until we reached the flats.

 

[AH3000MkIII]

Here is the factory tool...

 

[PSJ]

Gasp! the factory tool! highly desired; rarely seen; coveted by many; available to few. At the risk of turning this discussion completely sideways, does anyone have resources or references for duplicating (or replacing) factory tools? My Dad has his Healey; and we both have MG's; and if I had a doller for every time I wished I had a referenced "factory tool ABC", I'd . . . probably still not be able to afford them.

I've ordered manuals, so that we can have as much reference material as possible. In the meantime, we'll target the number provided by Bob Hughes, above.

And lastly, we do recognize the difficulty of keeping the socket aligned with this very narrow nut! We're going to have to be creative on that one . . .

 

[Legal Bill]

Like I said, grind down a socket. A machine shop could do that for you in about five minutes.

 

[bob hughes]

What does the manual say?

Bill

The Good Book refers to the manual, it is in the section regarding the rear hub.

But you are right about taking care. The other thing is to always replace the locking washer with new as a safe guard.

There is a story buzzing around in the New Forest section of the AH club UK that a chap was cornering and the whole half shaft came out, not sure what happened to the car though.



Bob

 

[Legal Bill]

Thanks Bob. Sadly, I posed my question thinking that I was responding to an earlier post. I did not see that the thread had already run to a second page and you had already mentioned "the good book." Us Americans; no filter between brain and mouth, no patience to hear the opinions of others before we hear our own.