First for me

[oldredford]

While driving back to my house in my 30 Model A coupe, I heard a very loud Ka Boom followed by the car jerking to the left. Sounded like a shot gun going off. I pulled over to see WTF is going on. Nothing visible so I shook the front fire and was amazed at what I found. The outer wheel bearing literally flew apart. The inner race had gotten so hot it welded itself to the spindle. Complete bearing failure. Now what caused this? Both bearing had plenty of grease and it was not over tighten. Strange....

[Patrick L.]

Kinda sounds as if the bearings were bad when greased or the bearing was defective from the start. Maybe the cotter had been left off.

[Tom Wesenberg]

I've seen that happen, but only if the bearing was dry or tightened too much.
I've seen the outer part of the hub shatter from the bearing being tightened too much.

[40 Deluxe]

Grease packed tapered roller bearings like the Model A front wheel bearings must not have preload! They need some end play, like .001-.005". If you tighten the nut past zero end play, thus preloading the bearings, you squeeze all the grease off the rollers and races. The bearing is now running dry, gets hot, seizes, the inner race starts spinning on the spindle, welding itself solid to the spindle! With a slight amount of end play, a film of grease stays on the rollers and races and the bearing lives a long and happy life-maybe 86-87 years and counting! (If cleaned and repacked regularly) No matter how much grease one stuffs into the hub, the bearings are only lubed by that initial film of grease on the rollers and races.
A tapered roller bearing in a differential, on the other hand, is under preload to hold gears in precise alignment, but here the bearing is lubed and cooled by a constant bath of gear oil.

[Eckler's]

wow! that's some scary stuff

[Mitch//pa]

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P

Originally Posted by 40 Deluxe

Grease packed tapered roller bearings like the Model A front wheel bearings must not have preload! They need some end play, like .001-.005". If you tighten the nut past zero end play, thus preloading the bearings, you squeeze all the grease off the rollers and races. The bearing is now running dry, gets hot, seizes, the inner race starts spinning on the spindle, welding itself solid to the spindle! With a slight amount of end play, a film of grease stays on the rollers and races and the bearing lives a long and happy life-maybe 86-87 years and counting! (If cleaned and repacked regularly) No matter how much grease one stuffs into the hub, the bearings are only lubed by that initial film of grease on the rollers and races.
A tapered roller bearing in a differential, on the other hand, is under preload to hold gears in precise alignment, but here the bearing is lubed and cooled by a constant bath of gear oil.

Why are model A grease packed tapered roller bearings different from say a 1982 ford mustang utilizing grease packed tapered roller bearings

[Brentwood Bob]

That is how I was taught. Others disagree. I snug the castellated nut, then back off one slot, spin the tire, check the vertical movement for obvious looseness, then install the cotter pin that is a tight fit in the hole, and run it.
Bob

[40 Deluxe]

Mitch, they're not. Every late model Ford service manual I've looked in says something like: 'tighten adjusting nut to 25 ft. lbs. (or similar figure), rotate hub several turns in each direction to seat bearings, then back off nut until completely loose and readjust to achieve .000-.005" endplay'. Other manufacturers have similar instructions that give the same results. I spent the last 27+ years as a mechanic for the Arizona Hiway Dept. More than once a vehicle would come in with a destroyed front wheel bearing (usually the outer) and the driver would say "It was just in such-and-such shop" so I would check history on the computer and find it just had brakes or its yearly service and see new wheel seals on the work order. So I would check the bearings in the other side and find them adjusted way too tight (significant preload) and see signs of imminent failure (totally dry bearings and discoloration although the hubs were full of bright red Mystik grease.

[Mitch//pa]

I'm not one for putting much if any preload on and I am also not one for leaving it go with any end play either. I like 0 no end play or a hair more 0+,, 0+ 3/4. After driving it's possible they can loosen to a very small amount of endplay, I would then remove the play. If that was to happen...
Here is the spec for the mustang with the same style bearings.

[BILL WILLIAMSON]

You can read & hear ANYTHING, or be TAUGHT" by ANYBODY, but did the "teacher"?? know what the F**K he wuz talkin' about????
Some outer wheel bearing failure is caused when someone re-adjusts a loose bearing & doesn't AT LEAST pop out the outer bearing & pack it!!! The inner will usually have enough grease to go awhile longer. I DON'T jist BABBLE, I've had a DAMN lot of EXPERIENCE & if that sounds like bragging, WELL----------------------------------------------------
Bill W.

[Tom Wesenberg]

An important note in the picture Mitch just posted is step #3 says 10-12 inch pounds, and not foot pounds.

10-12 in. lbs. is equal to 1 foot pound or a hair less.

[bbrocksr]

Originally Posted by Tom Wesenberg

An important note in the picture Mitch just posted is step #3 says 10-12 inch pounds, and not foot pounds.

10-12 in. lbs. is equal to 1 foot pound or a hair less.

Or finger tight.
Bill

[Mitch//pa]

But not loose and no endplay

[The Master Cylinder]

Originally Posted by Tom Wesenberg

10-12 in. lbs. is equal to 1 foot pound or a hair less.

Is that a RCH or less?

[Mitch//pa]

Originally Posted by The Master Cylinder

Is that a RCH or less?

U bad

[BILL WILLIAMSON]

Originally Posted by Mitch//pa

U bad

The Master is not BAD, Mitch, just EXPERIENCED! By the way, it's speled RKH, not RCH!!
Bill W.

[harleytoprock]

I prefer blond, so do I use the same torque spec?

[rowens55]

Originally Posted by harleytoprock

I prefer blond, so do I use the same torque spec?

Depends if its bleached or natural......

[SeaSlugs]

Originally Posted by Brentwood Bob

That is how I was taught. Others disagree. I snug the castellated nut, then back off one slot, spin the tire, check the vertical movement for obvious looseness, then install the cotter pin that is a tight fit in the hole, and run it.
Bob

yea, ive done it a dozen times or so on modern cars ive got a feel for what appears right or too tight. important to always spin the tire/hub both directions.

then mount tire on it and really let it whirl and see what its doing.

[Brentwood Bob]

Bill, I want my zip it rack back now.
Bob

[BILL WILLIAMSON]

Originally Posted by Brentwood Bob

Bill, I want my zip it rack back now.
Bob

WHY???????????????????????????????????????:ee k::ee k::confuse d::confuse d:
Bill W.

[Brentwood Bob]

Bill, sent you a pm. Hope that explains it. I think the comments above helped make others aware of the need to take care with the proper adjustment of the tapered bearings. Apologise for the comment in #20. Please ignore it. I had a bad day. Bob