Harmonic steering wobble

Well the second Britpart Dynamic Damper has now started doing the same thing, the boss was with me collecting the Christmas Tree and she was not amused, it's so violent it's frightening! As soon as I hit any bump in the road on a slight bend at over 35 mph it does it and I have to slow down to stop it happening and creep along. The whole vehicle starts to shake violently if you don't react immediately. The old 50,000 mile OE one never allowed this to happen but both the Britpart ones have, and I thought I was making an improvement changing it. Another vote for "if it ain't broke....." Still not got my money back from Paddocks for the first one so what chance another claim.

I'll have to buy an OE one now or the 90s undrivable.

How are you doing with the similar situation Austin?

Reply to
Bob Hobden
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Swivel pre load ?

Reply to
johnty

Yes, we have been down this road and I have yet to check it but why should changing the damper cause this problem if it's the pre load? It didn't happen with the old damper.

Reply to
Bob Hobden

"Bob Hobden" wrote..........

Put another way, why does it need a steering damper?. If it was set up or designed right then it shouldn't need a steering damper. It's near impossible though to balance the wheels properly with most 4x4 tyres and a vehicle that gets knocked about off road even if the pre-load etc. is ok. I had the same problem when one end of the damper broke off, practically undriveable, but I couldn't find any other obvious fault. It's still ok with a new OE damper.

Martin

Reply to
Oily

My '69 88" doesn't have a steering damper and ive never had any issues with wobble.....ex-friends disco had problems with wobble (despite new damper), checked and adjusted swivel pre load and all was fine.

Have removed damper from my D2 and dont have any issues with that either, steering dampers in my mind shouldnt be fitted in an attempt to cure a fault (as far as i know they are more for trying to stop the wheel being whiped out of your hands when say hitting a bit of rough)

As to why its doing it now with the new damper.......did you compare the two for correct function.....are the bushes softer on the new one....did you prime it .......did you check for correct function at the mid point of travel (where the damper would usually sit )

Reply to
johnty

My 1974 SWB Series 111 didn't have a damper and that was always OK, excellent steering, however this 1986 90 has had a damper (and power steering) from new and obviously needs it. I will do the pre-load when I get time but really can't see how that could be the problem when it didn't happen with the old OE damper I took off or with the present one at first. Just came on suddenly and dramatically whilst driving yesterday, like something broke/failed. I understood the pre-load problem creeps up on you, it doesn't happen suddenly.

If a vehicle is fitted with a damper by it's manufacturer then it's for a reason, they don't waste money. My understanding is if you take one off you need to inform your insurance Co. because you have modified the vehicle. I do hope you don't have what I experienced yesterday, perhaps at a higher speed, and have a nasty accident as a result.

Reply to
Bob Hobden

Errr... I thought the bit that goes through the chassis on a series vehicle had a friction damping system built in? Two cones keyed to the shaft mating with cups attached to the outer tube with a rather large spring trying to force them apart. I know you've got to be careful when you strip it down, as bits tend to embed theselves in you, the workshop wall or ceiling, depending on which way it's pointing.

Reply to
John Williamson

OK perhaps i didnt make my point clear enough.........

I removed steering damper from D2 because i fitted heavy duty track rods....these dont even have the fittings for a damper (due to their weight its unnecessary so im lead to believe and ive certainly not had any sort of problem with it, and yes its listed with my insurance company.

As to your sudden problem (perhaps its somehow lost fluid/got an air bubble/fallen off)what i was trying to get across was that loss of damper by whatever means shouldn't cause such a profound problem if everything else is in good order, which is why i mentioned the ex-friend with a very similar problem (and the swivel adjustment which cured it for him). The preload problem would creep up on you by the fact that its something gradually wearing that creates it (which could be masked by your oe damper(did you have the problem before you changed dampers?))

As to the steering relay acting as a damper, since friction is involved it must do to some effect, however it can be that perfect because steering dampers were fitted to some series vehicles

Reply to
johnty

In which case you're covered until the police or VOSA say that it was a contributory cause to whatever they're booking you for.

I'm not the OP, and I have no problems with my steering. I was just trying to point out that Series vehicles *do* have a steering damper of sorts fitted, it is just part of another component. As for external steering dampers on Series vehicles, I sit to be corrected, but aren't they needed only on vehicles with power steering?

Reply to
John Williamson

My 109 has a steering damper fitted (its not a retrofit cause the chassis has the bracket as part of it so does the drag link....i so wish it had power steering on it)

Vosa dont seem to have a problem with it.....we get a stop and check quite often round here and my D2 has been inspected by them twice so far this year local plod must think all landrovers are running on red (i suppose its the price of living so close to one of their favorite spots).

I know your not the OP i was just trying to reply to everything at once......

I think i'll stop trying to help and go back to just lurking

Reply to
johnty

The steering relay is not meant to be a damper.The idea of the tapered bushes and spring is to make it self adjusting.Years ago I had an S111 brand new without power steering but it had a steering damper.

Reply to
mark

Sounds like we both have a case of that.

Apparently, I read the book wrong, too, when I did, many years ago.

Reply to
John Williamson

I sit profoundly corrected.

I'll just go and lurk behind these tyres, then....

Reply to
John Williamson

On my Disco we've never had a really bad problem, but when we did get a slight wobble replacing the rear A-Frame bushes cured it completely!

I reckon that all the links and bushes on Landrovers are a contributory factor, it only needs one to fail big style and the rest soon go ... so I'd suggest checking _all_ bushes, front and rear. There's a distinct possibility that although it's a steering wobble, there may be nothing, directly, wrong with the steering!! ;)

Also worth checking tyres are pumped equally and wheel bearings are in good fettle, along with the obvious as has been said earlier in the thread, like the swivel pre-load etc.

Reply to
Paul - xxx

I have no doubt you are correct, a slow deterioration in all bushes/bearings cannot help my situation, it is a 1986 vehicle after all, even if it's only done just over 50K miles. Certainly the A frame is something I have to get round to.

Reply to
Bob Hobden

No sadly, my old 109 needed one, even though the swivel pre-load was OK, bearigs too etc and the steering relay. Not a "problem" per se', but it was a whole lot nicer to drive with the damper, than without.

Dave B.

Reply to
Dave Baxter

Paddocks have told me today that they are refunding the cost of the first damper but as this is the first one they have found faulty they have suggested.... "The customer who had a similar problem was advised to check his swivel pins and all his bushes, as this could cause problems if they are worn. He found a worn bush which he replaced and this cured the problem. This may not be the same with your vehicle but we would ask if you could double check them"

Reply to
Bob Hobden

I think that Paddock have been very good to you! A damper that is dead as you take it out of the box is, I would have thought, almost impossible.

I'm going to make myself unpopular by suggesting that all the reported 'cures' brought about by changing the damper are not cures at all but rather a decent damper concealing a fault or multiple faults elsewhere.

An earlier poster was correct in stating that a steering system in good condition does not need a damper. The fact that Land Rover have fitted one as original equipment for reasons other than to produce a working steering system doesn't alter that.

If you want to see the difference between a system that needs a damper and one that doesn't try the following:

a) Jack up the vehicle so that both front wheels are off the ground. Operate the steering by turning the steering wheel or grabbing hold of a road wheel and moving it to replicate a steering movement. Note that there is no 'springness' in the system, nothing oscillates if you give it a sharp rotational movement and let go. This is not a sprung system which needs a damper to control it. Do this with the steering damper connected and disconnected. All that you may find is that there will be more resistance to quick movements with the damper connected. Land Rover provided the damper for some protection from impacts (things that snatch the steering wheel from your grip) either in off-road use or of more relevance to the condition of today's roads when dropping into potholes. The presence of the damper can improve the steering feel as has been mentioned as it damps out external shocks.

b) Bounce the bodywork up and down at one end of the vehicle or the other with and without the suspension dampers connected on the axle in question. It should be obvious that the damper is an essential part of the suspension system. The dampers control the oscillation of the sprung system. (Don't try to drive with the dampers disconnected!)

Things, of course, aren't always that simple. There is a connection between a steering component (the damper) and the front suspension - but in its lateral motion rather than the vertical motion. The steering damper can help to control that lateral motion (i.e. that of the front axle relative to the chassis) under some conditions. It is this 'by-product' that enables some front suspension faults to be concealed by a working steering damper.

I've gone on too long.

Bob, the steering damper isn't your problem. It's probably: a) swivel pin bearings or pins (and not just the pre-load as is usually mentioned) b) front suspension bushes (panhard rod and axle to radius arm) and their hardware and bracketry. c) front dampers (shockers) ... or any combination of these.

I'd suggest that you start by getting someone to rock the front wheels vertically whilst you view from the back. There should be no motion between the swivel ball and the housing. Do this with the wheel loaded and on the ground (which unloads the upper bearing) and hanging free from a raised axle (which unloads the lower bearing). Also try levering the wheel upwards away from the ground in the latter condition. I don't think that you will like what you see! My money's on the lower swivel bearing being shot. This would fit your description because if the lower bearing becomes unloaded by going over a bump (compounded possibly by a duff shocker) location at the lower swivel pin is lost and the wheel is 'flopping about' in all directions, wheel tracking is lost etc. - a big shimmy!

If you can give that area a clean bill of health then move on to the front suspension bushes. As I've mentioned here before the condition of the bracketry is frequently ignored. If the internal tube of the bushes (only about 3mm wide) cannot seat fully on the bracket because the bracket holes are elongated and/or the bolts worn you'll never get the bushes to work properly. Loose bolts or bolts that don't stay tight are a symptom of this.

Reply to
Dougal

Thanks for that Dougal, a plan of attack is always useful. :-)

Reply to
Bob Hobden

On or around Wed, 9 Dec 2009 08:22:26 -0000, "Bob Hobden" enlightened us thusly:

The heater's f*cked in the Rangie and I'm buggered if I'm driving it in the current weather without a heater.

Mine still wobbles a tad, but it's bearable - it was the damper that made the most obvious difference to mine - and I didn't even fit a new one, just a better one. Maybe the 90 is worse because of the shorter wheelbase and different dynamics?

handy info about the britprat dampers, though: I was wondering about some of theird for the disco II, which needs all 4 changing. I won't bother now, either stick with OEM or there are some others to think about.

Reply to
Austin Shackles

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