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When I replaced my bearings in October, I didn't tighten the castle nut any tighter than it was when I removed them. The old bearings were shot, one was discolored from high heat and whatnot.
Anyway, I tightened the nut up by hand till it was tight, then backed it off about a quarter turn. The wheel spun freely.
When I got new tires put on, the tire techs noticed my bad tie rods and said I had "looseness in my wheel bearings."
I could use some advice from those more familiar with greasable tapered roller bearings.
Happy Bricking
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Ok, as if this wasn't confusing enough. Let see what the Volvo Manual says about wheel bearing. Oops, shouldn't have done that. It seem that their are three castle nut and two different ways of installing the bearings depending on the type of nut. If you have a 12 or 20 slot castle nut you tighten to 41 ft/lbs. while rotating the wheel during the last stage of tightening. Then loosen nut a half-turn. Ensure outer bearing's inner race has not stuck. Tighten nut until it is only just possible to move axial washer radially with a screwdriver. Loosen nut about a half-hexagon so that split pin can be installed in the nearest hole. After installing and locking bearing, hub should rotate easily, but without any play.
The second method is for a 20 slot castle nut with integral washer. Tighten castle nut to 42 +/- 5 ft/lbs.. Rotate wheel during tightening. Afterwards loosen nut a half-turn. Ensure outer bearing's inner race have not stuck. Tighten to a torque of 1.1+/- 0.5 ft/lbs. (finger tight)(finger tight is what it say's in the manual) Then turn nut to nearest hole and insert split pin. Their are two places in spindle where split pin can be installed. After installing and locking bearing, hub should rotate easily, but without any play.
And I thought threads starting " What's the best oil" were fun,
Ron J
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Perfect answer.
Also, you can use the same procedure on a 70's Chevy Pickup or the like. Or a boat trailer. Or pretty much anything RWD.
The only improvement I've seen on this setup prior to the one piece sealed bearings in FWD's (if you call that an improvement) is on 70's/80's Mercedes/Porsche stuff with the locking adjustment nut set up such that you don't have to find the closest hole/notch, you lock it down exactly where it should be.
One might be able to retrofit such to a Volvo if it'd fit under the dust cap and the threads are the same on the shaft. I think they are more coarse on the Volvo though. Mercedes and Porsche were extremely anal about the tension of the front bearings and there effect on the front end geometry, it paid off too.
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Ron, I think you're making the 240 bearing adjustment sound needlessly complex.
Referring to the 6-step procedure on Bentley page 770-4: Steps 1 and 2 (initial torque) apply to all 240s. Steps 3 and 4 (nut tightening) differ slightly because of a bearing change in 1981. Steps 5 and 6 (cotter pin and hub cap grease) couldn't be simpler.
There is no mention of the number of castle nut slots, (which I've never seen mentioned before), but that seems like a non-issue to me.
--
Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.
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Lucid,
It probably does seem overly complicated when you read it, but basically it's tighten to spec, back off, check to make sure the bearings are seated, loosen just enough to insert split pen. Oh and the Volvo manual say the 12 slot castle nut was replace with the 20 slot nut but it does not say when. Probably so you don't have to loosen it so much to insert the split pin.
Just quoting from the Volvo Manual,
Ron J
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Hi,
If you get a good technical service manual, it will advise you to use a torque wrenches. Some suggest both foot-pound and inch pound wrenches.
Be sure that both the bearings have their outer races seated into the hub. They are to be against their internal shoulders and checked with a mirror, if you have replaced them.
This should be been done before the final assembly. Since this is what you are about to do when you are putting the wheel back on.
The specifications can vary slightly, mostly from the size of the bearings or mass of the hubs. Seating pressure is 25 foot pounds and up to 50 foot pounds while rotating the wheel. The lowest number is more appropriate for car spindles.
The whole goal is to set the bearings rollers into their tapered races and excess play out. The inner and outer race of each set of the front and rear bearing in their place. It is important that the inner race of the rear bearing be set against the rear spindle shoulder in the process.
After the wheel is torque to its seating pressure. Some reset specifications vary with design of how to back off the nut.
Some say back it off one flat of the hex nut (60 degrees) or about one quarter turn that is 90 degrees. Another favorite is slotted metal caps, one slot, or even two slots approach phrased, “which ever is closer to a cotter pin hole!”
All of us would like to feel with certainty and confidence that we did it right.
The idea is to use the pitch distance of the thread on the spindle to arrive at a clearance distance to allow for a running fit and to allow for heat generated by the brakes. The problem is this will vary with each manufacturers spindle and nut design even though the bearings have to operate the same.
Now in my opinion, snug is a term that is a variable. It is like the 60 to 90 degrees being the same as 60 out of 90 mechanics that can and will feel snug, differently.
This is where I myself have determined over the years to use my torque wrenches to narrow the field to a standard. Machinists like standards because that is what makes things interchange with each other. Eli Whitney had something to do with that just a few years ago!
When I do the final release and reset with the wheel stopped, I have had good success with using those foot-pound numbers converted to inch pounds.
One-foot pound to two-foot pounds converts to 12 inch to 24-inch pounds.
I can use a foot-pound wrench and look for it to wiggle up to a reading of about one-foot pound, which is not accurate.
I like using my INCH pound wrench a reading 12 or higher up to that 25-reference number seems to works great. That way I keep that 25 number as a maximum, in my head, for the whole job on these cars.
Anything in between is a fair game in my ballpark.
The 25-foot pounds seating pressure works well on my pickup too. I have yet to use it on my motor home but since the tires are much larger, some extra seating pounds might be necessary.
Overall, I will stick to using the light feel and expanded reading of an inch-pound torque wrench for obtaining a running fit up for ALL tapered bearings.
Phil
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Wow. Haha. Thanks!
Thanks everyone for their replies actually. I'll convince a friend to let me jack up my car at his house and re-do it. I did tighten them down, then back off the nut about 1 flat spot, but it wasn't precise and I would rather not have the bearings go bad again.
I got them both looser than tight, and tighter than loose, but how much looser and tighter was up for debate :P
Happy Bricking
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Actually, the bit about a seating pressure is only for brand new bearings and races that have just been installed in the hubs. to seat the races. The actual Timkin spec for tapered roller bearings ( and this is ALL tapered roller bearings ) is 8-10 ft lbs per inch of bearing diameter across the wide side of the rollers , in the case of combination bearings where there are two dissimilar sized bearings, the smaller of the two is used for determining the torque spec. so if the distance across the rollers of the outer bearing is 2" then it would require a torque setting of 16-20 ft lbs. Now , here is where reality and common mechanical folklore collide, often violently. you DO NOT back anything off. You set the torque wrench to the lowest of the settings for the spec which in this case would be 16 ft lbs , and if it doesnt' line up on a slot for the cotter pin, you ADVANCE the nut to the next available hole which , but design, will be right around the 20 ft lb mark. You will never have a properly torqued and greased bearing fail, but one that is installed loose will fail in a heartbeat. THat is what causes that discolouration overheating and premature failure.
And yes this information is accurate. I was lucky enough to have an instructor who had retired as one of the top bigwigs at the Society of Automotive Engineers ( you know, that SAE you see stamped on everything, these were the guys who made all the rules . He used to keep a hundred dollar bill on his desk for anyone who could prove him wrong on anything he said in class ... Nobody ever got the bill, but it sure kept us on our toes :-)
--
-------Robert,'95 960, '93 940t, '90 240 wagon, '84 240 diesel (she's sick) , '80 245 diesel, '86 740 GLE turbo diesel, '92 Ford F350 diesel dually
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Sorry Dude,
Bearings require a positive clearance, NOT a 20 Ft/LB preload.
Goatman
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It's kind of funny. For the handful of us in captivity who have been through certification in transmissions and differentials , nobody ever argues with us about the requirement of preloads on timkin tapered roller bearing in differential pinions, but you put that same bearing in a wheel spindle in a front end( which I'm also certified on as a master mechanic ) and everyone gets their BVDs in a bunch because the rumors have been out there for so long that running bearings loose has even begun to appear in some manuals, but that doesn't make it correct. The manufacturer of the bearing still requires a preload for the bearing to function properly. When a tapered roller bearing is loose it works against the cage and eats itself up as the rollers wobble back and forth, when it is set with a proper preload, the cage remains in a neutral position where the lube keeps it floating freely and the rollers remain steadfast in their track and no damage is caused.
This does not apply to new style encased bearings like are found in the 960 and the FWD models as they have their own set of rules .
--
-------Robert,'95 960, '93 940t, '90 240 wagon, '84 240 diesel (she's sick) , '80 245 diesel, '86 740 GLE turbo diesel, '92 Ford F350 diesel dually
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R,
Please reference the authority from which you obtained your information.
Timken’s own literature states that bearings are NOT to be preloaded. Who should I believe? Timken’s own literature, or someone who tells me that they are wrong?
‘‘The bearing
end-play is equal to the total indicator
movement, which should be between
0.001” and 0.007”.’’(Step #8, Bearing Adjustment)
http://www.timken.com/en-us/solutions/automotive/aftermarket/lightduty/TechTips/Documents/Vol1Iss3_Wheel_Bearing_Replacement_English.pdf
Goatman
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Timken’s own literature states that bearings are NOT to be preloaded
Goatman
I don't see this stated specifically in the document you cite. Is this from another Timken publication? If so, could you tell us please, which one and where it can be accessed?
--
'80 DL 2 door, '89 DL Wagon
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This I can do. If you haven't settled on a repair method for this let me know, and we can fix that.
Paul
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Bulletproof,
Preload = negative operational clearance.
Now let me provide a non technical stipulative definition.
Because the bearing surface and rolling elements expand when the temperature increases, they require a positive clearance at all times (there must be a space for the metal to occupy). If, because of installation error or excessive running temperature due to improper lubrication, the running clearance may become a non positive value. At this point, there will be no more space for the rolling elements to occupy, and the bearing surface will radically increase in temperature. This increase in temperature will then exacerbate the problem by even further reducing the operational clearance, leading to a further increase in temperature. This is known as ‘‘Thermal Runaway’’, and generally results in the total failure of the bearing element, if unchecked.
This is why roller bearings generally require a positive operational clearance, in order to allow for the expansion of the assembly.
Preloading is the intentional elimination of the operational clearance, and can be useful in some situations where speed and load is limited, to provide additional rigidity to the rotating assembly. The automotive wheel bearing is not one of these applications, and a few thousands of an inch in play is totally acceptable.
http://www.kamandirect.com/resources/2010/downloads/skf_bearing_failureandcauses.pdf
Goatman
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Maybe you could explain how every car with a rear axle uses a preload on the pinion bearings, and the side bearings, and lasts for thousands of miles? Maybe you've seen a 3/4 truck with full floating axles? Huh? And then explain how the outer axle bearings are PRELOADED and don't burn out?
Go back to your job at Cape Canavaral pinhead.
Just because you once changed wheel bearings, one time, doesn't make you the expert.
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Flathood,
If you could have explained it, maybe you would have. Maybe you would like to?
Yes, you have utilized the fallacy of Ad Hominem, in an attempt to provide support for your weak argument. Not that I really care, it just shows your true desire to mock, and not really know the truth at all.
‘‘Pinion bearing preload is measured in inch-pounds’’
http://www.differentials.com/install.html
Goatman
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So you're agreed that preload is OK with tapered roller bearings? Good. Rludwick is shown to be right, and hopefully he's pleased with your conversion.
Glad you figured it out Rocket Scientist.
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Thanks for the complement! I’ve always wanted to be a rocket scientist!
Again, you’ve committed another logical fallacy. This time you’ve utilized a ‘‘Straw Man’’ fallacy. By attacking a misrepresentation of my position, you hope to support your weak argument.
I actually previously admitted that bearing preload was useful to increase the rigidity of certain rotating assemblies. The pinion gear is one application where play is detrimental to the strength of the machine.
Automotive wheel bearings are not one such application.
Goatman
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Well This is a very disturbing change in attitude on Timkins part. I got my information over 30 years ago originally from Texts provided by Timkin during training and I recently checked on their website as soon as couple of years ago the last time someone questioned me on it to see if they had changed their tune to that procedure and at that time it was still holding true to the letter, but it appears in the last few years that they have changed their mind. I will have to dig deeper to see if that applies to all bearings or just recently manufactured ones as there was a certain batch of bearings they had started manufacturing quite recently as of last few years for some new production equipment that followed a loose setting , but they were quite specific about that only going with those particular bearings and not the rest. But this is aparantly showing all of them following those guidelines .
It's a bit disconcerting to think they have changed their minds across the board on that one. It usually takes a long time on cars, but on semi truck wheel bearings you can put a temp gauge on a wheel that has been properly torqued and one that has been set loose like that and the loose one will get hotter than a firecracker very quickly, and if left that way will need a seal replacement and the bearing will be shot in a very short time where the properly torqued one will go 2-300k miles or more before needing a seal and the bearing will still be fine
--
-------Robert,'95 960, '93 940t, '90 240 wagon, '84 240 diesel (she's sick) , '80 245 diesel, '86 740 GLE turbo diesel, '92 Ford F350 diesel dually
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Well many year ago I had a 56 Chevy and I started to hear that rumble sound you get when a wheel bearing start to go bad. So I go to the parts house an get a set of bearing, install the bearing finger tight like dad said, and away I went. Well couple months down the road and the rumble is back. So off I go to the parts house for another set of bearing. Installed the new new bearing finger tight like dad said and off I go. Well a couple month more down the road a you guessed it, rumble is back. Well it's morning at I had my coffee and it time to visit the library, if you get my drift, and I decided to take the owners manual with me, not a service manual the owner manual. It says to tighten the bearings to 33, I don't think I'll ever forget that spec, ft/lbs then back off to insert the split pin. I never had anymore trouble with the wheel bearing.
Ron J
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'56 Chevys used used ball bearings in the front hubs, not rollers.
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Mopar gets the gold star. You are right, I forget that part. If I remember correctly ball bearing are preloaded and roller bearing are not.
Ron J
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Exactly. A nice tight bearing will not fail. but a loose one is a disaster waiting to happen. THis new thing from timkin has me concerned. I have a bad feeling that those new style bearings that were coming out on the new vehicles have been in service long enough that that are considering the old style ones an end of life product , since most vehicles the age of our bricks have long since been boneyard fodder, so the trend would be to cater to the current service product and let end of life products fall where they may since that is not their primary market. Like a lot of manufacturers, they most likely aren't too concerned about longevity on vehicles that have a very limited life expectancy ( same reason Autozone offers a lifetime warranty on their parts, because they know the majority of the cars the parts are going into are only a year of two from the grave so they have limited exposure to financial liability in parts replacement)
--
-------Robert,'95 960, '93 940t, '90 240 wagon, '84 240 diesel (she's sick) , '80 245 diesel, '86 740 GLE turbo diesel, '92 Ford F350 diesel dually
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Dude really, you need to get a grip. Your attack is bizarre and way off base.
He learned what he learned, it seems to have been changed possibly, and he calmly and rationally provided a clear possibility. Whether it's accurate I do not know, but it was no, NO, reason for your vitriolic attack.
Stop it, now.
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Install newly packed bearings and then install the thrust washer and nut.
Tighten the nut with a pair of large adjustable pliers while rotating the wheel. Continue to tighten until there is considerable resistance in rotating the tire. Stop rotating the tire and stop tightening the nut.
Without moving the tire loosen the nut with the pliers. Finger tighten the nut. Install new cotter pin.
Randy
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For the type wheel bearings with the castle nuts and thrust washers--not too tight--not too loose--you want it just right. Here's how to do it. Snug the nut down with a wrench or pliers to seat the bearing--not cranked down hard--just snug. Now back off until you can get a screwdriver blade slipped between the thrust washer and the hub to slide the thrust washer side to side by twisting the screwdriver. You want to be able to slide the washer easily--there should be nearly no play in the hub at that point. No play at all and difficulty moving the washer means too tight. Too much play--too loose. -- Dave
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Will, I was thinking they should be looser than tight and tighter than loose, but Trev had the right words.
--
Art Benstein near Baltimore
The quickest way to double your money is to fold it in half and put it back in your pocket.
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Rather than tighten by hand then back off, I tighten with a wrench to seat the bearings, then back off (until wheel spins freely).
Tightening by hand may not seat the bearings, so looseness may show up later. Easy fix, though.
--
1980 245 Canadian B21A with SU carb but electronic ignition and M46 trans in Brampton, Ont.
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