Steering and Suspension Wheel Bearings

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Tex Ritter - Not sure if the front wheel bearing is worn or not?

The bearings on the front wheels are 'tapered' bearings (cone shaped to look at).

The front wheel bearings are correctly ajusted by slowly tightening the hub nut so that when all the lift has been taken off the taper bearings you should be somewhere near a split pin hole: carefully tighten to the first split pin hole you come to after you have taken up all the lift, always use the correct size split pin, and never slacken the nut back to suit.

HarryMann: Yes, take up all the slack... 

Re-check after a while. If there's play in the 12-6 O'clock axis there should also be play in the 9-3 O'Clock axis as well, if it's the bearing, but this harder to detect due steering moving. See if you can detect this too, or get someone to look behind as you move it, if disc moves between calipers at all, it'll be the bearing.

Johnmck: Thanks! Don't appear to have any 3.00 and 9.00 oclock movement on front

HarryMann: Well, to be sure then, you need to watch the hub itself (as described) when you rock it vertically, to ensure the movement is in the bearing and not one of the suspension joints - Yes? Maybe you can get a good enough grip to rock it when the wheel is off?

NB. Front Syncro bearing/hub nut 30mm AF


Tightening rear castle-nut: Rears are 350~375 ft-lb. Go to about 350 ft-lb or so and then on to the next split-pin hole when tigthening. Loosening rear 46mm castle-nut

Bearings: Inner is a ball-bearing, retained with a circlip and the outside one is roller bearing with a thick-walled spacer between them.

The outer rear bearings are plain roller bearings with a spacer/sleeve between it and inner ball-bearing. They usually come as one unit (but without the spacer which doesn't usually wear, a thick-walled hard-steel tube). These can be really tightened up to their required torque using a 3/4" drive socket, 'T bar' and a 4' tube, if you still have movement when they are torqued up then you'll need new bearings (but read-on below!). Divide your weight (in lbs) into 350 and stand that far along the bar (in feet), then on to next split-pin hole.

Johnmck: Thanks! Rear is a little bit but much less than 6+ 12

HarryMann: Rears often move in and out (axially, as if along the shaft), and sometimes rock from new in the vertical plane, but shouldn't rock in both planes if bearings are OK.... Some say this is acceptable (even normal), whatever it is I haven't discovered yet, nor does a new bearing set always resolve it. This is usually a result of a worn hub bearing carrier (more likely) whereby the bearing outer race moves in the housing, the inner one usually. The (outer) roller bearing is designed to float as the hub nut is tightened up, but the (inner) ball bearing's outer race could with advantage be loctited in, after it's been driven firmly up to the locating shoulder in the hub.


ArmyPhil: The old bearings collapsed when taking them out rollers everywhere, upon fitting today though the bearing housing would not slide up the shaft after a little bit of emery still no luck, going to have another go tommorow because its hammering it down.

HarryMann: The outer is a plain roller, and although rollers caged, it's a very loose cage, so can easily do that. The inner race is separate and as you say may not slide easily up the shaft, its intended to be a tight fit, the shaft needing driving out and the assembled housing tapped back down onto the shaft.

You need the axle upright (fixed) and lower the hub onto it, with 3 hands (!) drifting v.carefully the inner race down the shaft if necessary, long thin drift or thinwalled tube, no jumpy off into cage (or jolt it down by dropping whole assembly onto axle flange a few times, hardwood/dead square of course :). Then drop the spacer down, fill void with grease as far as poss, then making sure all the rollers are stuck back out of the way with grease, slide the inner race into place, use a collar/thinwalled tube or drift if necessary. Don't let it come back out before fitting the drive flange after the backplate.

That seemed the best way when things got all greasy and difficult. I wouldn't emery the shaft much, just clean it but you could freeze it first with that cold-freeze spray.

Removing the bearing housing from the radius arm

The housing is bolted to the rear radius arm flange with 4 x 22mm hex head bolts that pull up into slight recessed counterbores (spot-faced casting) which can make using normal ring spanners a bit difficult. They are torqued to about 80 ft-lbs, not excessively difficult to loosen. To remove, best first remove the brake back-plate to give straight in access and then find a good tight fitting 22m socket, one with a thin-wall will usually go fully onto the bolt heads. Some flange-drive sockets will work, impact sockets though tend to be too thick-walled.

Wire-brush any thread protruding at rear and a power-bar and a bit of a whack usually gets them loose, and easily wind out. Alternately a well fitting ring and sometimes even an open-ended can loosen them. Good access is important. But the right socket is the best method. Drive it on if necessary. Garages tend to use heat on the bolt heads, but they aren't usually that bad. If stuck, could try shocking them with a bolt drift, but you might need new bolts afterwards.

Recent forum questions (2008)

Dubstar: I've found a bit of play in one of my rear wheel bearings. Are they adjustable or is it a replace only job?

HarryMann: Not adjustable, often play is just in one plane, vertically, due to wear of bearing housing.

Redstar: Snap! I have play in mine but I dont have any noise coming from it... do I need to zap mine out too...?

Titus A Duxass: I've had play in mine for the last 4 years. I think they come with play built in.

The MOT man said "ignore it until it really whines"

HarryMann: Leave then... Up to the point is starts to hum, drone (actual bearings) or the play just gets too much, which it can eventually... but if its just a slight top-to-bottom rock with no real side-to-side play then leave it I think... having 'done' several and they still rock vertically! Pretty sure this is the rear (ball-bearing) outer race rocking in the housing that has slightly ovalled - if you do change the bearing(s) then clean up the shoulder this sits againts if any burrs at all, drive [i]outer [/i]race well home and use Loctite Bearing Fit or similar, having fully degreased the housing and outer race first..

Some also have innate in-out play; again, it's been suggested to leave unless excessive, can't work out where this comes from unless it's wear/fretting of the housing or retainer circlip.

Methinks a lot of this is that the original design was for the lighter Bays with 13" wheels, we are now often using 15" wheels and the Syncros of course give them an extra hammering at times.

Other things to do

Covkid: Check your driveshafts carefully too. If you do decide to replace bearings, do both sides.

HarryMann: I suppose going on Cov's reminder, because the bearing housing is off, driveshaft hanging loose, brake-backplate off etc., it's worth saying that:-

Those outer CVJs should be looked at closely and re-packed or replaced at the same time, and also a good opportunity to service (clean and rust-treat) the brake-backplate (see brakes section for backplate removal and servicing) and in fact, clean and check the brakes generally.

Always have a very good look at the brake pipe that runs across the top of the radius arm, particularly where it sits in the plastic clip - I had one burst there !!! Brush it down and take a good look for any pitting corrosion that has got a hold, 99% might look fine, but...

psychonauts rear hub replacement in pictures

Hacksawbob Note: It might be an idea to loosen off the castle nut and wheel nuts before raising the van. Psychonaut removes the CV joint outer before undoing the castle nut. There is no need to do it this way and put yourself through the hassle of getting to those CV bolts in the trailing arm. You can undo the inner CV joint and the whole drive shaft will come out through the trailing arm once the bearing housing is undone. This makes getting the bolts off much easier with better access. Also see Jed the spreads video [1] Jed doesn't remove the brake lines from the back plate and removes the unit in one piece. Depending how old your brake lines are may determine whether you can get away with doing it this way. He was able to knock the axle in to give clearance enough to slip the back plate off. My axle was not for moving when I did this, but it does give you better access to the 4 bolts that hold the bearing housing.

caption drive shaft with both CV's assembled attached to the bearing housing being re-inserted into the trailing arm...but for pyschonauts description read on...


caption The first thing to do is get your van's arshe up in the air, crawl underneath her and get the drive shaft off, starting with the gearbox end

caption I used a ratchet and hex key as all mine were hex, but sometimes you'll find that some of the bolts are star-shaped - I have a set of star sockets for the Triumph so if I'd have come across any it wouldn't have been a problem.

caption Next is the end of the drive shaft inside the bearing housing at the wheel end. This is renowned for being a bit tricky. I used an extension bar on the ratchet, and tied up the free end of the drive shaft with string out of the way so that I could get to all the bolts. They all came off bar one,, which was starting to round off as I tried to get it off. In the end I hammered a 10mm (If I remember correctly) onto it with the extension bar, which was a tight enough fit that when I put the ratchet on it, it started to turn. At this point, I order a set of bolts from the Bay of Fleas to replace some of the dodgier looking ones I'd taken off!Next is the end of the drive shaft inside the bearing housing at the wheel end. This is renowned for being a bit tricky. I used an extension bar on the ratchet, and tied up the free end of the drive shaft with string out of the way so that I could get to all the bolts. They all came off bar one,, which was starting to round off as I tried to get it off. In the end I hammered a 10mm (If I remember correctly) onto it with the extension bar, which was a tight enough fit that when I put the ratchet on it, it started to turn. At this point, I order a set of bolts from the Bay of Fleas to replace some of the dodgier looking ones I'd taken off!

caption When you've got the driveshaft off, stick a plastic bag over each end to save any muck or grime getting on the joints, or any of the grease coming off them and all over the family cat or the baby, and pop it somewhere safe for the duration of the job.

caption Next job is to remove the split pin, and get the castle nut off. It's a 46mm socket - I had to buy one especially, just over £20 from a local tool specialist. Ouch. Once the split pin is out, you'll almost certainly need to put the wheel back on, drop the van back to the ground, and then loosen the castle nut.

caption With the van back in the air, and the nut off, it's time to remove the drum. It'll be full of brake dust so be as gentle as you can be. Remove the two retaining bolts first, then simply pull the drum off. Mine needed a few persuasive taps around the edge with a hammer to remove it.

captionUndo the brake line at the rear. I clamped the rubber part of the brake pipe to minimise fluid loss before doing this. You will still need to bleed the system afterwards though.

captionThe wheel mounting plate should now pull off, although you may need to offer some "gentle persuasion". Once it's off, you'll have all the gubbins inside the brake drum on view. I'd advise taking a photo or two at this point if you're not familiar with how everything goes together, so that you can put it all back together again properly when you've finished :) This is mine, but after I'd started taking springs and retaining clips out. Photograph yours before you start.


captionOnce the bearing housing is off, I recommend following the instructions in the Haynes manual. I did, they're very clear and accurate, and so long as you follow them exactly, you wont go wrong. I wont reproduce the process here, but a couple of photos may help :)

Lifting out the oil seal at the inner end of the bearing: -


caption And the circlip underneath it

captionDriving in the outer bearing with a bearing placer: - Drive out the old bearings with a drift, available for no more than a couple of quid at your local tool specialist. Don't use a screwdriver or anything else big and hard!! An undersized bearing placer would also work. I used a combination of the drift and a small placer.

When putting in the new bearing parts, follow the Haynes, and pack *everything* in as much grease as you can. I already had some wheel bearing grease for the collection of motorcycles I have, but Halfords do pots of temperature-tolerant grease especially for wheelbearings for just a few quid. The bearings I bought from Brickwerks had a sachet of grease supplied, but I'd buy a pot anyway. You just know that sachet will end up in the (a) dog, (b) mug of tea, or (c) the baby.

captionPopping in the outer seal. As you can see, I used a block of wood rather than a placer for this, and tapped GENTLY and squarely to ensure it went in evenly

captionThe finished job, before putting everything back on the van: -


Loosening rear (46mm)hub nuts

Techniques - Loosening rear hub nut

Loosening front hub nuts