Overheating Front Hubs

C

Curtis in MA

Senior Member
This winter I replaced my king pins and steering arms. Used the same bearings but cleaned and repacked them. Now after 10 miles my hubs are 120 degrees.
What did I do wrong?
 
My guess would be that the bearings are too tight. Did you bring them up snug while spinning the wheel and then back off to the first cotter pin hole? I only assume that your brakes are not dragging since you would have probably noticed that

Charlie Stephens
 
How did you adjust the bearings? There must not be any preload! Modern specs are .000" to .005" free play. If overtightened, the preload forces the grease out of the rollers, the bearings heat up, expand, and get tighter. The only time a tapered roller bearing is preloaded is when it runs in a bath of oil, like in a differential.
The Model A Handbook says: "tighten the adjusting nut until the hub just starts to bind. Then back off the nut one or two notches until the hub can be freely revolved."
The Service Data Handbook that came with my '40 (identical wheel bearings) says: "the nut should be run up just barely snug, then back off approximately one-sixth turn (one slot on castellated nut) so wheel turns freely. Always back off nut rather than tighten to replace cotter pin."
i might add that the brake shoes must be backed off if needed so there is no brake drag.
 
I agree too tight. Ruined a set of new bearings on a pickup once the same way. I less than 100 miles they were shot and screaming. Repack if they don't look blue and galled. I was told that loose is way better than too tight.
 
Curtis, are you sure it's the bearings too tight or are the brake shoes dragging a little bit? That is the other variable here.
 
With the cars' weight on the bearings, 120 Degrees is NOTHING!!! Quit fussing around with those Harbor Freight temp scanners & DRIVE it!!!--STUFF is supposed to get warm!
Use a High Quality, High Temp, disc brake wheel bearing grease, preload the bearings to 5 Ft. Lbs & you're THROUGH & SAFE! IF your cotter pin hole doesn't line up, search for some thin, steel washers, of varying thicknesses & put one between the Big, keyed washer & the nut, until you find the one that lines up a castellation & the spindle hole.
Bill Practical
 
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BILL WILLIAMSON said:
With the cars' weight on the bearings, 120 Degrees is NOTHING!!! Quit fussing around with those Harbor Freight temp scanners & DRIVE it!!!--STUFF is supposed to get warm!
Use a High Quality, High Temp, disc brake wheel bearing grease, preload the bearings to 5 Ft. Lbs & you're THROUGH & SAFE! IF your cotter pin hole doesn't line up, search for some thin, steel washers, of varying thicknesses & put one between the Big, keyed washer & the nut, until you find the one that lines up a castellation & the spindle hole.
Bill Practical
Click to expand...

I may be new to model A's but could someone explain to me why the front bearing tightening procedures should be different than any other car with similiar bearings? Les Andrew's & Bill's procedures seems to reflect the "normal" procedure. What's the fuss?

John
 
aermotor said:
I may be new to model A's but could someone explain to me why the front bearing tightening procedures should be different than any other car with similiar bearings? Les Andrew's & Bill's procedures seems to reflect the "normal" procedure. What's the fuss?

John[/QUOTE
You're TOTALLY RIGHT. They're the same design as most TIMKEN bearings. They require a snug fit, to support the weight evenly, to move the grease around properly & to steer smoothly.
LOOSE bearings causes races to "wobble" around & wear out HUBS!
AND, how can you even set the TOE-IN???
Properly packed wheel bearings can go an easy 30,000 Miles, with a slight RE-ADJUSTMENT, at 15,000 Miles!
Bill Practical
Click to expand...
 
I had some work done on a ‘79 ford truck “that I couldn’t done at the time “ They said we packed your wheel bearings, good I was going to. Well on bearing didn’t get grease packed into the bearing and it got really hot and blued the spindle. Should have taken it back but I fixed their FO. Hopefully you know how to pack bearings?
 
I’ll try state how to pack by hand, better to see hands on. Clean bearings throughly and DONT spin by air gun as they will fly apart. Put a Glob of grease in the palm of one hand, with the other hand put a finger or two through the bearing. Then roll the bear into the grease pushing grease into the opening of the bearing “the ring where the roller ends live” the grease will be pushed between the rollers and out to the side. Move around the bearing doing this until you have grease all around the bearings. I said I would try to explain, maybe someone on U-tube shows how to much better than I tried.
 
The videos I saw tried to push it in the wide end until it came out the small end. This didn't work for me.
Someone said to get a bearing packer.
 
When I install the front hub bearings I clean the threads of the spindle and the nut to remove any and all grit.


I tightened the nut down tight and shake and spin the assembly to be sure the bearing and race are seated. I then loosen the nut until the washer can move with a screwdriver and then tighten the nut to the next available notch for the cotter pin.
 
I searched this issue in the archives and see that it goes back to at least 2010. I think it equals the discussion on which oil to use and will never be agreed on. In my short time with model A's I have never run into any problems following Les Andrew's and the Service bulletin books. So, I guess do as one of these recommendations or however you want - it's your car.
Just saying. :D

John
 
A bit off topic, but one for someone to get their teeth into to do with wheel bearings.

We have a camper trailer that has military grade suspension that looks like this:
https://www.campertrailers.org/trackmate15.jpg
It uses Ford car bearings from the 70's. The small outside bearings need to be greased every 5000k's otherwise the grease turns to black powder by about 8000 k's and by 10,000k's the bearings die. The hubs run cool even when the bearings are on the way out. Any ideas?
 
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