www.jec.org.uk

I recently replaced the droplinks and tie rods on the rear of my S-Type,since carrying out the repairs the rear of my car seems to have a mind of its own,especially on wet or slippery surfaces. I think I may have disturbed something while doing the repair like a outer wishbone bush as the left hub was able to move quite a bit with the tie rod removed. I am thinking about using polybush replacements. Any comments or help would be appreciated especially with regard to removing the old bushes as I do not have access to a press.
This is my 3rd Jag and reminds me so much of my Fathers 1961 3.4 Mk2 and I love it, so any of you out there who think this model is just a rebodied Ford(I was one of these) think again, this car is going to become a true classic Jaguar - definately Grace, Pace & Space

Hello Tony,

My initial thoughts are that now you have replaced the tie rods with integral outer ball joints from the subframe to the rear hub is that the rear tracking may be out of limits. However from what you describe as movement which I assume is between the lower hub carrier link and the outer patent bush in the lower rear wishbone unit implies that you may have a problem with worn lower wishbone bushes.

These bushes are unique in design. I wrote a big article on the subject in our magazine last year about them. There are three bushes in the lower rear wishbone. One is a hard wearing long life rubber Metalastic type unit which seldom gives issues. That is the bush in the wishbone found effectively just to the rear of the sill. The two other bushes are the patented type and are a notorious wear issue on the car.

Now then. This is where the fun starts. Originally, these lower rear wishbone units and their bushings could only be replaced via Jaguar as a complete unit at around £470 per wishbone! Later, Neville Anderson at North East Jaguar Spares found an alternative source of supply for these wishbones and began to make them available at a much more affordable price.

Later still, Racing Green Cars Ltd managed to source replacement bushes for around £50 each. Neville now stocks these bushes as well as complete new wishbone units. We all breathed a sigh of relief when these replacement bushes hit the market but it should be noted that fitment of those bushes is not a Jaguar approved repair method due to the risk of wishbone register cracking occurring.

These bushes are not a normal item generally found in wishbone units and great care is needed in fitting them if you go this route. A bench press is needed for removal and fitment of new bushes and a specially dimensioned mandrel must be constructed to facilitate those operations. Use of ratchet sockets as push mandrels are rather unsuitable due to incorrect wall thickness and other dimensional issues. However given the right man and equipment for the job, it can be done but you must expect that a wishbone may crack during the rebush process. Fitment is at your own risk. Note that a 20ton+ hydraulic bench press is also required to change bushings. Attempting to do such work with even the largest of bench vices, tubes, spacers and other cobbled up paraphernalia is a non starter. So that is the basic start point for rear wishbone replacement or repair given that wear is evident in one or both wishbone bushes.

Replacing the link rods could well now cause excessive wear in rear wishbone bushes to become evident and your car to handle like a tea trolley as a result. I`d suggest you go over the rear wishbone bushes with a fine toothcomb and replace any worn items.

Having done that, I would also be looking at the front suspension for wear issues. Begin by ascertaining that wear is not evident in the outer steering rack arm ball joints. Then jack the car at the front to lift the tyres to a height of around two inches and insert a lever bar between the ground and the bottom of the tyre. Have someone lift on that bar whilst you look for up and down movement between the lower from wishbone and vertical hub carrier vertical leg. The ball joint fitted to the bottom of the vertical leg is a frequent failure point on early pre MY2002 S-types. That done, also lever all wishbone inner bushes and check for wear also in the upper wishbone ball joint. Wear found in that location means fitment of a new upper wishbone arm. Again Neville can supply these at good prices.

Having found and replaced all worn suspension items on all wishbones and vertical leg ball joints, THEN have the car retracked using a four wheel alignment system. Don`t bother to have the car tracked until you are totally satisfied that all bushings and ball joints are in a condition fit for further long term service. Only by use of such equipment car the car be made to drive in a straight line and handle correctly. Correctly set up, the car will be a joy to drive. If that is not the case then intensive investigation is needed.

Polybush do indeed market bushing kits. Expect to spend at least £500 for a kit! I must however add a word or two of caution. I have examined one of these kits and am personally greatly concerned about the suitability of installing solid polyprop bushings within the lower rear wishbone. Doing so would in my opinion destroy the special design aspects of the original patent bush which allows tangential and circulatory axial movement which is needed within the jointing of the lower wishbone unit. The use of a poly bush at the wishbone/lower hub carrier location would make rear tracking adjustment almost impossible as a poly bush would solidly fix alignment and not allow rear tracking adjustments to take place. In all other wishbone locations on the car, I can see no reason why Polybush bushes should not be used.

http://www.polybush.co.uk/shop/697_Jagu ... _1999-2002


Seen how you get on with these ideas and come back to us if you still have problems.

Mike K

Thanks Mike,the bush you refer to as a metalastic type, is that the outer bush or one of the inners ? When I had it apart and the tie rod removed the rear hub behaved like it was the front ( it would swivel about its vertical axis) if you understand what I mean. There is also a knock from the lhr over speed bumps which was not previously apparent.

The knock is probably shot anti roll bar bushes.

"Bonk- thonk" indicates anti roll bar bushes are shot. Suggest best source for these is SNG Barrett. I say this because they sell polybush type replacements for virtually the same price as the soft, squidgy, soggy original items. Bonk-thonk often seems to originate from places seemingly unrelated to where the wear actually is. Lever the anti roll bar against the body to see the movement. Same both ends of the car. Off side front bush can be a bugger to change. The compressor limits access. Best hint of the day now. Disconnect vertical links both ends of the anti roll bar and jack wheels clear of the ground. That off loads an ARB and bushes can then be changed relatively easily. If that is not done at the front, you can go blue in the face changing the osf bush!

"Click - clack" indicates anti roll bar to wishbone vertical links are worn. Neville the Devil can fix you up with those at the right price.

As regard the back end, the rubber Metalastic bush on the lower wishbone is the big black unit immediately behind the sill and virtually in front of the rear wheel. Those bushes are almost bulletproof.

What you describe at the joint between the lower hub carrier to lower rear wishbone bush is a characteristic of the bush design. Hence my previous comments about the speciality of the bush which is patented. The internals are effectively a 3mm thickwall tube with about a 12mm diameter ball at the mid point of the tube. The tube and integral ball can rotate in a thin wall ball shaped nylon "bearing". That arrangement allows for rotational movement AND a small degree of axial tube movement within the outer bush housing. If that axial movement were not available you would not be able to adjust rear tracking. Hence my worry about the patented bushes being substituted with solids as sold in the Polybush kit. To my mind, the concept and operation has not been fully understood by the designers of the poly type bush.

So you will find that the hub can turn to a limited degree if you disconnect the rear tie rod at the bolt through ball joint. This is quite normal. What you need to check for is excessively loose movement when the ball joint bolt is removed and for lift and general slop if you lift the hub up and down with a stout bar with the suspension off loaded, road wheel off and car on an axle stand or large timber blocking stack.

Hope that helps clarify.

Mike

Thanks
I will check this out next weekend

Hi Mike,

I've read this post with interest and taken one of my rear wheels off again to understand what you were refering to. I've also been looking at this with a view to adjustment if/went I have to replace part of the rear or for that matter the front suspension.
Is there an offcentre pin to adjust castor and camber or is it all fixed, with only rear tracking needing adjustment.

Would you consider replacing the front bush in the front lower wishbone with a polybush item?

Brian

PS sorry if i've hijacked this post.

Hello Brian.

No, you`ve not hijacked the post at all. It is all part of the same issue.

To my knowledge and in my own experience, there are no cam type bolts or pins which can be used to adjust camber or castor. So all points are jig fixed at the factory.

The knock on effect is that if an S-type suffers a major smash and the vital body frame location points become dislocated, then the term" bent" really does mean bent and body jig alignment would be required to restore accurate caster and camber angles. If not repaired correctly the car would handle like a Jenner going back to his hotel after a good night out in Newcastle.

I`ve frequently considered replacing standard front wishbone bushes at the front end of the car with a poly bush type. The reason for this was that as far as I was concerned, the early S-type suspension was not up to the standard I required. Consider this scenario.

Car manufacturers produce a product which suits the majority of buyers ie it does the job adequately within a range of A >R. Then along comes someone like me who finds A>R way short of his requirements and the only practicable way around it is to start personal modifications. If I get it right, the car performs from A>X which satisfies my need and the previous issues become a thing of the past. But how is it done, what choices are needed and which mod kits do I fit?

In the case of my own MY2002 4 litre, with similar issues being experienced with a previous MY2000 3 litre car, I developed a profound aversion to the performance of initially the front suspension. It would bang, crash, bounce, wallow, under steer and the front end jump sideways if the car was driven with any spirit. Scuttle shake was also a very big annoyance. I considered fitting a front suspension turret brace but although fitted well aft of that location, a rather flimsy version of the idea already existed on the car. This is mounted under the front edge of the black plastic windscreen wiper scuttle panel. So no mods feasible at that location.

I then considered poly bushing the front wishbones but in 2007 poly kits for the S-type were not available. So that idea got junked.

Then Geoff Adams at Adamesh began selling lowered and uprated spring kits at a humble £265 at set. I fitted a set and handling improved and some of the wayward characteristics reduced. Then came a set of 19" rims and 35% tyres. Another good improvement but still the suspension lacked decent damping and finesse. I then fitted Bilstein gas 30% uprated sport dampers to the car. A total transformation and a much firmer drive with all the previous irritations being alleviated. This was all achieved to my total satisfaction without wishbones being poly re-bushed.

Would I fit them to J44 now given that the car handles so well without virtually solid re-bushing being fitted? I think the answer must be, no, I would not fit the super solid poly bushes but I might consider the softer material option offered. If I were to fit hard bushings, I think J44 would become incredibly hard nosed around town and the driving experience would become too much of a good thing. The car would become something akin to a circuit racer and be extremely uncomfortable as a road car. One must also consider that it is not unknown for suspension wishbones to be torn out of car body structures due to extra strains being imposed and fatigue based structural failure occurring. Rare, but it does happen.

Then there have been longevity issues concerning polyurethane bushings. Some bushes have been collapsed and become unstable after a relatively short period of service. What however is not frequently understood and is often overlooked is that there are several grades of poly bush type material used in the manufacture of suspension bushes. Selection of the correct material gives many miles of driving satisfaction, whilst an incorrect specification or cheap version can lead to disappointment. I suppose best advice would be to discuss your specific needs if you decide to move away from standard bushing parts. The final decision must lay with the purchaser and it would be wise to accept that you are really entering into something of an experiment if you fit this type of after market part. Results obtained may or may not work out well.

What was the question?!

Mike

Thanks for the reply Mike, I'm erring on the side of caution as I went down the road of poly bush with our MkII.

Due to known front suspension bushes knocking out very quickly, they were all replaced with poly but the subframe bushes left in rubber. The rear torque arm rubber bushes died after 2 years and a free rear suspension kit from 'Polybush' was trialed, but I replaced the leaf spring centre and front pads in rubber due to harshness on our concrete motorway. Bushes both poly and rubber have survived well over 12 years and I believe that poly in the RIGHT place is fine but not everywhere.

Finally the main reason for our discomfort in the MkII was the 'original' front springs which last year were found to be soft (thinner wire) , probably from a lighter daimler rather than the heavy 3.8 engine and the gas tank in the rear changing the suspension frequency front to rear.

As you can imagine we have found the 'S' type a revelation in comfort (not used to modern cars). so I'm lothe to upsetting it too much (why have a bus pass when you can have an 'S' type). We just want reliability for our tenure of the car. Plugs and coils to change after the MkII is MOTed and a fuel filter I think.

I've been around the suspension bushes with a couple of heavy screwdrivers again and from your comment about movement in the 'patent' bushes it comes down to how much is too much. hopefully the next Castle Bromwich course will answer that if they bring the same subframes (I'll bring a screwdriver).

Brian

If you insert a close fitting screwdriver shank into the tube part of the bush and move the tube around from side to side, in otherwords moving the tube off centre from the central position in the case, moderate to high effort to move it indicates that the bush still has some service life left in it.

However if the tube will move around easily with little effort then the bush is well worn. If you can move the tube off centre with thumb and index finger effort, then the bush is well worn and needs replacement. You may also find the tube rattling around in the bush in which case it is totally clapped.

The centre ball part of the tube runs in a nylon type ball shaped bearing. If the ball has worn its way through the nylon bearing "cup" the wear will certainly be evident.
The image shows a sectioned bearing with the tube removed. Regret to say I`ve lost the tube section but this image shows the nylon bearing which in this case the wear through in the nylon cup at the top of the picture is clearly evident. Also worth noting the cracks in the nylon cup lining which also indicates this particular unit is very time expired.

I sectioned this bush with an angle grinder so I could see what was inside. Hence the melt and burn seen on the rubber parts of the bush. The ball and tube do not wear as they are considerably harder than the nylon bearing cup. It is the nylon cup which wears out and then allows the ball and tube to flop around inside the bush unit. If that occurs, the bush is finished and MOT failures result because the hub carrier bearing or the inner wishbone bush exhibits movement which can become dangerous. Suspension geometry also goes out of limits and the handling of the car can become wayward.

Most people would never go to the lengths I went to to find out how the bush functioned but I did this as part of my investigation for my wishbone article. To my memory it was published in our magazine sometime around Jan, Feb or March or 2011. I`ll dig out the article and try to give you a more accurate date.

The thing about these bushes is that they are either serviceable or they are not. On the car if they are worn out wear is easily detectable using a pry bar in the time honoured traditional way. If play is noted between the hub carrier and the wishbone or the wishbone to subframe bushings, then the bush is worn out. If no play is evident under leverage, then you may assume all is ok. It`s as simple as that.

Mike

Got it sorted!!! rear tracking a mile out - so much for measuring the new tie rods then!
Thanks to all who helped & the guy's at Merityre Bagshot for sorting it.

Centre to centre measurement with tie rods and similar units is never easy and invariably inaccuracies occur. In addition, measurements on the old rods may not have been correct. Someone may have previously messed with the car.

Only when a car goes up on the ramp and decent four wheel alignment equipment is strapped to the wheels, can true geometry be obtained.

Images here of my old hack, J44 being given the full tracking check. Rear wheel alignment equipment had to be cable tied to the rims as the car is lowered and the tops of the alignment gear had to be removed to get the gubbins under the rear wheel arches. A few minor tweaks later having ensured that all suspension bushes and bearings were still serviceable, the car was adjusted. thereafter, just for once it drove in a straight line.
Glad you got it sorted.

Mike