Swivel Hub Preload and shims

[isuzu110]

Hi all

I'm trying to eliminate shimmy in my steering that comes after hitting bumps on the road in my '95 Defender. I've replaced the panhard bushes and the radius arm bushes are only 12 months old.

I've taken some play out of the wheel bearing and replaced two of the three steering ball joints, plus replaced the ball joint on the steering arm.

It's getting better, but my drivers swivel hub still has some shimmy. I've removed shims from the upper swivel pin until I only have the thinnest shim left.

Can I actually run the swivel pins without any shims ? What's next if this does not eliminate it ?

Thanks

[PhilipA]

Well yes but have you looked at the swivel bearings?

If they are Brinelled, and that has caused the clearance to open , you will not get rid of shimmy even with the apparently correct preload.
Regards Philip A

[steveG]

If you've had play in the wheel bearing, and also in the swivel, I'd suggest you do the job properly and strip the hub and swivel.

I'm not 100% sure if the Defender's run the same style top pin as the earlier 110's, but having done my County ones recently the pins were quite worn and no amount of preload would have removed the play.

Do it properly and you wont have to worry about it again for years.

Steve

[clive22]

Hi,

I had the same problem with my County and followed the same path until the swivels were rebuilt, which solved it. Tried adjusting swivel preloads too.

What I found when I pulled down the hubs, and removing the swivel bearings is that the needle rollers had worn a corresponding set of radial marks around the straight ahead steering position.

When you increase the preload, by removing shims, you are driving the needle further into the worn/formed notch, which is why, I suggest, you've run out of adjustment, since it below datum.

When I did mine replaced all seals throughout: swivels, hubs, axle, etc.

Mine has bearings at the bottom bush/pin at top, later ones I think have bearings top & bottom. I needed to use my press for the bush at the top.

Clive

[biashara]

Everyone is giving the correct answers here. All components have to add up: Weight of steering rods, steering damper, tyre pressure, swivel pre-loads, tie-rod ends. Defenders have bearings top and bottom. Remove all shims from top and tighten top pin down untill pre-load of 5 to 6 kg is measured on a scale attached through the ball joint hole, and preload remains pretty consistent from lock to lock, measure gap between swivel housing and pin flange and fit correct thickness of shims. I did all of the above on a Disco 1 once, and it still didn't fix it, eventually discovered a couple of the radius arm bush bolts were loose, replaced the bushes, fitted new bolts, solved the problem!

[wrinklearthur]

If they are Brinelled, and that has caused the clearance to open , you will not get rid of shimmy even with the apparently correct preload. Regards Philip A
Hi Philip

Brinelled.

That's a word I haven't heard for a long time.

The problem with tightening the swivel pin bearings, when that has occurred, is that, the rollers can grab the wear marks and lock and then either the cup or the cone can then rotate, in / on their mounts.

Start looking for something like, worn tie rod and link rod knuckles, get someone to help, then gently swing the steering wheel and watch for any slop in the steering train.

Usually the swivel pins can be tested by jacking the vehicle up, just enough to take the load off the wheel, but still touching the ground.
Try it by grabbing the top of the wheel, then push and pull it, look at the top edge of the large seal, where it meets the ball of the swivel pin housing , see if there is any signs of movement.

[isuzu110]

Thanks guys.

I should add that I have already jacked the wheel up and rocked it vertically to diagnose the wheel bearing play and eliminated that.

I have also checked the steering damper which seems sound. I'd rather not rely on it to mask the symptoms though but address it at the source.

The preload seems consistent lock to lock. I was thinking that with brinelling, I'd get a different feeling coming into and out of straight ahead. Perhaps not with no load.

How big a press do I need to do the swivel hub bearings ?

[PhilipA]

How big a press do I need to do the swivel hub bearings ?
About 4 lbs manually held and a drift.

Regards Philip A

[Hartley]

If your steering goes funny after hitting a pot hole, there is a good chance it is due to incorrect toe-in. Especially if you cant get any vertical play when shaking a jacked up wheel.

[Davo]

Not that we want to send you off on a front axle rebuild for no reason, but usually the swivels are ignored for many years until something like this happens, and when you strip them down you find out just how bad they are!

[toc_bat]

is it the actual swivel pins that wear or the bearings or both? bye

[PhilipA]

I am pretty sure that a 95 Defer has the same system as an RRC ( not Railco bushes), so it will only be the bearings that wear.
Regards Philip A

[JDNSW]

is it the actual swivel pins that wear or the bearings or both? bye

Either can apply. Considering first the older setup with a railko bush at the top and the tapered roller bearing at the bottom. Wear on the fibre thrust washer results in free play on the bearing (and if let go, lines of wear on the races in the straight ahead position). Adjusting preload brings it back to spec. The actual bush is a tightish fit on the pin, and any wear on either the pin or the bush will result in wobble. This can only temporarily be removed by adjusting the preload. But significant wear on either the bush or the pin is unlikely except over a very long period, provided they are lubricated properly. After all, there is a large area, and not much movement. But having free play in the vertical direction will exacerbate wear.

The later type with roller bearings top and bottom will last indefinitely without attention, provided they are properly lubricated and never have any free play. Preload should be sufficient to ensure that even under the most severe bump or rebound conditions no free movement develops. (As an example, the wheel bearings on my 110 have done over 500,000km - consider how many more turns these have done than have the swivel bearings.)

For both types, allowing free play to continue will quite rapidly damage tapered roller bearings, especially on corrugated roads, and lubrication failure will rapidly damage both types, especially if the lubricant is replaced with water or mud.

John

[toc_bat]

thanks for the informative replies, when i 'changed' the swivel pin fluid i realised they were almost dry, maybe 50ml in each, and after filling up one of them has a minor leak so the next thing is to try to seal the leaks, and hence i suspect maybe the bearings will need attention or replacement, are both the top and bottom the 606666 bearings?

bye and thanks again

[PhilipA]

(As an example, the wheel bearings on my 110 have done over 500,000km - consider how many more turns these have done than have the swivel bearings.)

The difference is that swivel bearings just sit there still most of the time with the steering at straight ahead, and impacts are made continually on a still bearing, causing them to form ridges coincident with the position of the bearing rollers.
You cannot compare wheel bearings with swivel bearings.
Regards Philip A

[toc_bat]

Hi all,

Just a question about the bearings involved, the part number 606666, am I right in saying it is a land rover part number, and not the bearing number? If so what is the number for the bearings, so I can maybe get them from the bearing shop before the job.

[PhilipA]

The bearings are not a common bearing, as they have a far greater angle on the cup than a normal rotating roller bearing as they must take much more side thrust than a normal roller bearing . More like a steering head bearing on a bike.
There are aftermarket ones but usually available from a LR specialist.
Regards Philip A

[toc_bat]

I read somewhere that the swivel housings were recommended to be filled with oil, this was prone to leaking so the later recommendation is the one shot grease method. Is this true? What do people use? Both my owners manual and workshop manual state EP80 or 90 oil.

Also if the whole thing is filled with oil, why would you pack the bearings and cv joint with grease? Isn't the oil bath there to lubricate these?

bye all

[JDNSW]

The difference is that swivel bearings just sit there still most of the time with the steering at straight ahead, and impacts are made continually on a still bearing, causing them to form ridges coincident with the position of the bearing rollers.
You cannot compare wheel bearings with swivel bearings.
Regards Philip A

Yes I can. Unless the impact exceeds the fatigue limit of the metal, which will not happen if there is no free play, when impact loads are likely to, the ridges will only be formed by wear due to lack of lubrication or contaminated lubricant. I did my swivels at about 400,000km, and the lower bearing races were unmarked - railko bushes needed replacement, and swivel pins had no measurable wear.

I stand by my contention that properly lubricated roller swivel bearings will last indefinitely.

John

[JDNSW]

Hi all,

Just a question about the bearings involved, the part number 606666, am I right in saying it is a land rover part number, and not the bearing number? If so what is the number for the bearings, so I can maybe get them from the bearing shop before the job.

Yes. Last time I was there (Series) I found that the bearings were "order in" from the bearing shop, and were three times the price of a Landrover specialist! But I did find that SKF has a cross reference for Landrover part numbers (actually found this several years ago when getting overdrive bearings).

John

[JDNSW]

I read somewhere that the swivel housings were recommended to be filled with oil, this was prone to leaking so the later recommendation is the one shot grease method. Is this true? What do people use? Both my owners manual and workshop manual state EP80 or 90 oil.

Also if the whole thing is filled with oil, why would you pack the bearings and cv joint with grease? Isn't the oil bath there to lubricate these?

bye all

From 1948 swivels were supposed to be filled with oil. From about 1993? this was replaced with so called "one shot" oil or "semiliquid grease", and this can be used for earlier Landrovers as well. never use ordinary grease, as the top bush or bearing will have a short life, as will the CV or U-joint. The grease packing of the wheel bearings is to provide initial lubrication on assembly - up to about Series 2, this was not specified, but there was a filler plug in the drive flange to allow you to fill the bearings with 1/4pint of oil on assembly.

John

[JDNSW]

thanks for the informative replies, when i 'changed' the swivel pin fluid i realised they were almost dry, maybe 50ml in each, and after filling up one of them has a minor leak so the next thing is to try to seal the leaks, and hence i suspect maybe the bearings will need attention or replacement, are both the top and bottom the 606666 bearings?

bye and thanks again

The swivel seal (the large one) will leak if there is any play in the bearings, so this may be the problem.

John

[toc_bat]

well i did it this afternoon, stripped one of the swivels, the one with the more prominent leak. Interestingly the leakier one had very slight freeplay in the system when I rocked the wheel. The other one doesnt even drip on the ground more of a weep and it has considerable freeplay.

This is what I found,

The tapered rollers are perfect, no pitting or brinnelling or noticeable wear or roughness. The ball had a bit of a gouge taken out of it, possibly in some accident or maybe the steering lock was not set up right, there were also coils of steel at the bottom, looked very much like bits of helicoil insert.

Also there was no gasket between the seal and the seal retaining plate. In my manual and various online fiches there should be a gasket. But i note of all the kits for sale on ebay, none has this gasket despite having all the other gaskets and seals.

The seal was very hard, and is not an interefernece fit in the housing, in fact there is quite a gap between the housing and the seal, either it has shrunk or a gasket should have been fitted.

I suspect that the rocking I felt when i tested the wheel came from loose wheel bearings and not the swivel bearings. I just went and tried the other wheel when it rocks it is moving independently of the swivel.

bye for now

PS Bearing Industries in Yennora have a listing for a kit for both swivels, all the bearings, oil seals (6 oil seals all up i think) and gaskets for $180.

[toc_bat]

by the way the bearings in mine are Timken 11590, which is a standard size, Bearing Industries have NSK ones for $16.50. Much cheaper than any land rover place I think. In fact these bearing suppliers have consistently been the cheapest and most knowledgeable in the last 15-20 years that I have been mucking around with bikes and cars, very often when another bearing shop has told me that the bearing or seal I have doesn't exist, they will often have it on their shelf or know who to order it from. PS SKF make the same bearing, in fact they all use the same number, 11590.

[isuzu110]

Ok, as I started this thread, I'm now circling back with an update.

The root cause of the issue was rubber panhard bushes that were shot, despite being 3 months old. I suspect that when I fitted them, I had the vehicle jacked up and when the bolts were tightened, they loaded the bush in the wrong place leading tube to delaminate from the bush when the vehicle lowered to the correct height. This delamination led to play in the bushes.

Interestingly, the vehicle did not exhibit any death wobble when towing my 900Kg camper trailer. When the trailer was removed, the death wobble was encountered on potholes at speeds over 60kmh. The loaded trailer was doing something to the physics of the vehicle.

I replaced the panhards with superpro bushes (previous good experience with them and much easier to change in/out when the time comes again.

I bought the parts to rebuild the swivel housings and it took about 3 hours to do the side with the least preload. The bearings were not brinelled so I am yet to do the second side. The vehicle drives great.

After eliminating the issues and roadtesting, I finally replaced the steering damper with a Terrafirma RTC type.

[McDisco]

Good to hear you have it sorted mate. I had the same diagnosis issues with my rangie. I started with the panhard bushes, then replaced the dampener, tightened wheel bearings, then rebuilt the hubs, drilled and rotated the swivels and adjusted the swivel preload, corrected the alignment, replaced the tie rod ends and it finally tracks true and doesn't wobble. So many possible causes to look at. Each change improved it further. Only have to adjust the steering box for play now...

Angus