Difficulties installing & torquing rear drum - Help!
 

Hi guys & gals. Read every Ford Barn post I could find on the subject, Dick Flynn tips, etc. before starting to torque the 5/8 – 18 axle nut and found out the conventional wisdom is a final torque of 200- 225 foot pounds. Proceeded very cautiously inching the nut on and carefully measuring every 10 or 15 foot pounds. When I got to 175 the nut failed. The nut, by the way, was purchased from a well known reputable Old Ford V-8 parts vendor. I took it down to my local NAPA parts house to see if I could get a replacement. All they had in stock was a non-castellated variety (not surprisingly). They guy behind the counter felt that my nut was not a Grade 8 quality and, given my experience, I am inclined to agree which makes me wonder about the reliability of the folks that sold me the nut. I purchased a non castellated Grade 8 nut from NAPA and ran it on to the axle to see what would happen. Unfortunately it stopped before it reached the drum. So, I removed it and checked the axle threads which seem to be ok. So, should I run a 5/8 -18 dye over the threads to clean them up—or am I looking an axle replacement? And where do a get a Grade 8 castellated nut? Finally, do I really need to torque to 225 foot pounds? That seems like a lot.

Re: Difficulties installing & torquing rear drum - Help!
 

Be sure to get back to the supplier that sold you the original nuts and see what they say. Let us know how it comes out. Give them some advertising, good or bad.

Charlie Stephens

Re: Difficulties installing & torquing rear drum - Help!
 

I would check with Roy and see what he has (assuming he's not who sold you the original one!!)

Re: Difficulties installing & torquing rear drum - Help!
 

Is there supposed to be a thick washer between the nut and the drum?
What do you see is wrong with the thread?
If that is the recommended torque then that is what I'd do.
You may not understand this because I cannot think how to explain it. The hub climbs the taper on the axle and holds on the clean taper. It should actually work (drive) without the key (But of course you always use the key) This clamping effect is a result of that nut going up to torque. If the hub is not tight on the axle the two mating surfaces will "fret" damaging both.
Someone will direct you to a supplier (Mac VanPelt?) If not, Buy a grade 8 deep nut and have it slotted

Re: Difficulties installing & torquing rear drum - Help!
 

seems like an awful lot of torque considering age and possible condition of axle threads.I would have thought 175 would achieve a reasonable result. Cheers

Re: Difficulties installing & torquing rear drum - Help!
 

Original nuts were case hardened, nowadays would be more than grade 8----try taking a file to an original nut--it won't hardly scratch it

Re: Difficulties installing & torquing rear drum - Help!
 

Sounds like a thread problem. If it is, you only have two choices, re-thread or replace. To re-thread don't use a normal 5/8-18" threadchaser or die. What you need is an axle threader (note picture). This starts the re-threading in the center of thread travel not on the end where a die can go on crooked. As for nuts, I got two recently from Joe's Auto and they went on a '36 without a problem at 200+ pounds.

Hope this helps.

Tom

Re: Difficulties installing & torquing rear drum - Help!
 

In the Model A world most torque to 100 foot pounds so why 200 on the V8's ?

Re: Difficulties installing & torquing rear drum - Help!
 

Can you post a close up picture or two that would show us the condition of the axel threads? Also, if you send me an email using the Fordbarn system I can get back to you tonight with some info that might be of some help to you.

Re: Difficulties installing & torquing rear drum - Help!
 

I put on axle nuts to 150 ft/lb and then tighten until the castleated nut lines up with the hole in the axle. by the time I have done this , I am sure that I am in the neighborhood of 200 + ft/lb.

Re: Difficulties installing & torquing rear drum - Help!
 

Many venders are showing in their illustrations nuts that don't appear at all like the originals. The original Ford nuts besides being hardened are a full 3/4" long and the same diameter full length with no tapering at the slots. These are the must save items even when scrapping out a scrap rear end.

Re: Difficulties installing & torquing rear drum - Help!
 

Thanks for all the replies. I'll see what happens & give an update later. Be away for a few days--so probably next week sometime.

Re: Difficulties installing & torquing rear drum - Help!
 

I would think used original axle nuts would be easy to come by.

Re: Difficulties installing & torquing rear drum - Help!
 

No mater what the outcome you should run safety hubs or safety clips. You can get these four hydraulic brakes but unfortunately not for mechanical brakes.

Charlie Stephens

Re: Difficulties installing & torquing rear drum - Help!
 

With respect, only '33 and up axle nuts are slotted hex nuts while those used during the '32 model year and earlier were castle nuts (which taper at the slots).

Re: Difficulties installing & torquing rear drum - Help!
 

I have tried new nuts and found them wanting. Best course is to find originals.

Re: Difficulties installing & torquing rear drum - Help!
 

I like those original nuts that were a bigger hex size. I had just the one on a 40. I'm not sure which years they came on though. Standard hex size is 15/16" for a 5/8 nut, there are bigger, something like 1-1/16" (guessing here). Like mentioned above, saving the original nuts is a must. That said I have used aircraft quality self locking nuts (Philidas brand) on my roadster and I like those.

Mart.

Re: Difficulties installing & torquing rear drum - Help!
 

Before departing on a short trip for a few days (and getting back to the reality of the problem at hand) did some checking to satisfy my curiosity.

Here is part of a Ford Barn post from “Kens 36” dated 4-19-11: “A mailgram dated 10-20-47 (from the Ford Archives) detailed the procedure for assembling the hub and drum to the axle shaft. It specified use of a 24 inch handle and a torque of 300-350 foot-pounds. Service Letter A-25 dated 11-6-47 corrected the torque setting, stating: “tighten nut 356074-S to 200-220 foot pounds; then continue to the next castellation providing final resultant torque does not exceed 275 foot pounds.”

I then consulted (former and deceased) Ford V-8 Times great repair guru Dick Flynn’s article on the subject. Here is his recommendation. “Torque nut to 150-160 ft. lbs. of torque. The axle metal is grade 8 or better, 5/8-inch grade 8 bolt torque is 225 ft. lbs. So we aren’t even close to that."

So, obviously there is considerable discrepancy here. But 220 would appear to be pushing the outer limits if Flynn is correct.

Re: Difficulties installing & torquing rear drum - Help!
 

Re: Difficulties installing & torquing rear drum - Help!
 

Am attaching a photo of the end of the axle where the threads on the 5/8 -18 failed at around 160 foot-pounds. I have removed the 5/8” washer to expose the edge of the drum. As you can see, (bit a bullet) there are still good threads on the axle. This would appear to confirm that the bolt was not a Grade 8 quality or it would not have failed. I do notice that the end of the key way on the axle is showing (right side of axle). Should the key way be exposed? Is it possible that the drum is on too far? If I understand the theory of the drum to axle fit, seemingly it would be impossible to torque the drum on too far. Am I correct or--??

Re: Difficulties installing & torquing rear drum - Help!
 

First line in post #4, I mentioned a washer ...... Now that I have looked in a parts book, I will say again, "You need a washer" I think it is a fairly thick one.

Will a new nut (any one the right size) run on the thread easily?

Re: Difficulties installing & torquing rear drum - Help!
 

The keyway is normally cut into the threads some on these axles as a result of the cutter diameter they used, and the need to cut the keyway bottom flat enough in the area where the key normally fits.

After viewing this picture, which I had asked psogden to post here to get as many comments as possible on the condition of these threads, I believe these threads do have a good chance of surviving the specified torque IF an original Ford axle nut of the proper material and hardness is used. I had also suggested that the thick washer be removed when taking this picture so we could see the condition of the full thread length from the end of the drum snout to the tip/end of the axle.
Any additional comments by members here on thread condition, as seen in this picture, would be welcome.

Re: Difficulties installing & torquing rear drum - Help!
 

The washer is part number 351505 and it 5/32" thick.

Bob

Re: Difficulties installing & torquing rear drum - Help!
 

The washer is not in question here. He removed it temporarily at my request so that all of the axle threads would be exposed for the picture posted in post #20.

Everyone, please go back to post #20 and take a look at those threads, and comment on what you think of their condition. Are they likely to withstand the torque spec if an original Ford axle nut, with good threads, and the correct hardness is used? Your opinion of axle threads is what we are seeking here.

Re: Difficulties installing & torquing rear drum - Help!
 

Hi Everyone, JM I downloaded and enlarged the photo but I just couldn't see if the threads looked right, so I didn't comment. They looked at minimum, dirty, but the photo started to break down upon elnargement.

psodgen, I'd vote for more photos from lots of angles. Try Macro mode. Clean it first, maybe light wire brushing by hand.

Re: Difficulties installing & torquing rear drum - Help!
 

I agree with Jeff, can't be sure of the condition due to the presence of foreign material in the threads. Do not use a die to rethread, however. Pick out the sheared threads left from the nut, and wire brush to clean up.

BTW, I hope it wasn't you who used a BFH to remove the drum?

Re: Difficulties installing & torquing rear drum - Help!
 

Always use a KR Wilson drum puller. Will clean out threads further & post another picture. Appreciate all the replies.

Re: Difficulties installing & torquing rear drum - Help!
 

In reply to Bluebell, I do have the washer & pulled off as suggested by John before taking picture. I ran a brand new 5/8 -18 nut from NAPA on the axle & it went in about 1/2 way before tightening some so I didn't force. I do have one of those Bluepoint "thread fixer" tools but am reluctant to use it.

Re: Difficulties installing & torquing rear drum - Help!
 

A new, or good condition used nut should run down the full length of the threads freely. If the nut stops, it means the threads are either damaged or filled with crud. Bits of old thread or dirt. Give it a good wire brushing by hand and inspect it carefully using a magnifying glass if necessary. If I were you I'd buy a new nut if they are available locally and cut it in half. I'd put the nut halves around the base of the threads and clamp it on. I would then lubricate it and wind it off the thread while clamped tightly together. If there are any burrs on the axle this ought to straighten them up. Ok I know the axle is good quality and semi hard, but for the cost of the nut I'd give it a go regardless.

Mart.

Re: Difficulties installing & torquing rear drum - Help!
 

I noticed the BFH signs too...I suspect the person burned some calories on that brake job!

Re: Difficulties installing & torquing rear drum - Help!
 

Hi Everyone. psogden, A perfect photo would show the threads to the level of detail in the drawing.

Re: Difficulties installing & torquing rear drum - Help!
 

Maybe I'm missing something in this thread? Why not clean the threads really well, lubricate and run the appropriate die down the threads slowly, back and forth, until it
threads freely by hand. Get the correct axle nut and washer and tighten to the specified torque? If it holds, it holds...if it doesn't the it's axle time. The drum appears to have survived a violent history...the axle may have been a recipient of some of that violence as well. You know...how you use to screw the nut on to protect the threads and beat the shaft with a BFH. Am I missing something?

Re: Difficulties installing & torquing rear drum - Help!
 

I have a set of Little Giant dies which are adjustable--I would back the dies off considerably and thread the assembly onto the axle--Then I would tighten the dies to the axle and clean the threads from inside outward--Possibly in 2 or 3 steps--This way the threads would be true--Then use a nut that you know is good--If you can not get to torque spec without failure it would be time for axle replacement I believe--Don

Re: Difficulties installing & torquing rear drum - Help!
 

Good question. The reason you don't want to run a cutting die on it is because it has already been cut once, and to cut it again would remove material that should rightfully be straightened out, not cut out. I'd rather ruin a couple of new nuts straightening out the axle threads than to recut those threads. A previous post advised to split a new nut, assemble on the axle, clamp it tight, and run it back off. this is good, and there is also a tool available to do the same thing.

Re: Difficulties installing & torquing rear drum - Help!
 

Here are some closeup pictures of threads on several different axels that I plan to use in the next '35 rears I'll be rebuilding. I took these shots to show the profile of what I consider to be good threads on some good used axels. If you click on these thumbnail photos to enlarge them, then click and hold to get an option to open them in a new window, you can further zoom in on those threads to really see their profile.

Re: Difficulties installing & torquing rear drum - Help!
 

Another thought: Are you positive your torque wrench is calibrated correctly ?

Re: Difficulties installing & torquing rear drum - Help!
 

John, Those are some of the finest threads I've seen on axles! I do see some galling on the taper of one, and some nicks on another. These conditions should be addressed before calling it a day: Remove the axle key, file down any nicks, and install the drum with a wheel (for leverage), using grinding compound on the taper. Tighten the axle nut only tight enough to snug it up while allowing the wheel to be turned by hand, thereby lapping the taper in. Remove, clean off the compound, and make the installation with the key. If this is done, there will be no need to retorque later, and your axle will remain tight and secure.

Re: Difficulties installing & torquing rear drum - Help!
 

My 14" cheater bar (pipe) is in perfect calibration, thank you. :D

Re: Difficulties installing & torquing rear drum - Help!
 

Wow Nicely Played! Always trust the elbow!

Seriously wish I could imprint that on the 30 or so Noobs I hand a Torque Wrench each Semester.

Re: Difficulties installing & torquing rear drum - Help!
 

Think we are getting things a little mixed up here, JM was posting some examples of what he considered good threads would look like.