removing rusty front subframe and replacing it with sound 1

[555ttg]

Hello everybody!
Greetings from Canada!
My recent 'diamond in the rough' purchase of an 87 XJ-S HE coupe, has thrown me a curve ball,(googly!), in the form of a rusty front sub frame on the front right hand side of the frame. As we all know, this is not something that can be safely repaired, so a replacement sub frame is the order of the day. I read somewhere, that the front sub frames from the saloon cars are the same as the XJ-S cars. Would anyone here, be able to confirm or refute that?
I am sure that we have had this whole procedure covered in a past magazine article, but I wouldn't know where to look and the search that I tried didn't turn it up.
So here I am asking for any and all help, to try and figure out if this is a job that I can do myself?
I have a lift in my garage, I have the engine brace for the top of the car,(to hold the engine in place when removing the frame), I have willing helpers, workshop manuals etc. What I don't have, is the expertise of experience, never having done this before. I have thought about doing this with my LISTER XJ40, which also needs it's front sub frame replaced, but I haven't got around to it yet, so maybe the XJ-S will give me the confidence to tackle that, down the road.
If anyone has done this, and can give me any advice as to how it's done/how they did it/got on with it, I would really appreciate it. The books are one thing, but to hear from someone who has done it, is worth more than the books instructions.
So calling all XJ-S/XJ6/XJ12 owners who have gone through this, HELP!!!!!
Phil

[Brakebuster]

i did not have to replace the subframe, but i did drop it myself in my own garage, all safety requirements met....

Yes, the XJ6 subframe will fit the same ,

while your there, replace all perishable rubber mounts and bushes ,

then when the work is done, it will last another 20 years or more

first of all , you need to support the engine, then remove the steering rack , then the engine mount bolts , then the top of the dampers on the inner wings, then the rear mounts while supporting the frame ,

then the front pivot mount bolts ( in the 'six-shot bushes ' ) can be loosened , and the whole frame will pivot down to the floor from the front, while dropping away from the supported engine ,

easy as that,

be sure to use a proper spring compressor when removing the springs , but they dont need removing to from the frame to drop it....

the only word of warning is that the lower long pivot bolt can not be removed or replaced with the frame in place, it has to be worked on and reinstalled while the frame is dropped , otherwise it fouls the gearbox while trying to remove it backwards, trust me , i know , lol....

BB

[PaulGover]

Phil,
I replaced my subframe a few years back. There's no magic involved, just a lot of work - it's not going to be done in a weekend. Take photos of things like cable runs (e.g. for the oxygen sensors in the exhausts), bolt arrangement for the steering rack mountings, and take care to record the layout of all the spacers on the suspension and steering mountings. You'll need to get the front suspension geometry checked after the rebuild, and it's not easy to find a properly skilled place to measure the angles.

I used a home-made spring compressor - not recommended, it wasn't aligned right and the spring was strong enough to bend the 15mm threaded bar! Quite scary. I've read other ways of getting the springs off in various forums on the web, depends on how much confidence you have in the authors. Or hire the proper Jaguar tools.

As BB mentions, you will need to get the lower wishbone fulcrum shafts out. They require enormous applications of Ford special tool no 1 (5lb lump hammer), as they're invariably seized and rusted solid. It's probably easier to get them moving before dropping the frame. You can actually remove them with the frame pivoted down about the front mounting bushes, ditto the steering rack and exhaust fittings. Alternatively, you can buy replacement fulcrum shafts and saw through the old ones and then you only have to worry about using a press to replace the bushes.

I got interrupted for a couple of months refitting the subframe, and in the mean time the brake system had gained a lot of air. Mine is a facelift with the Teeves ABS, and it proved difficult to bleed the back brakes properly. If yours is the same, take care to follow the workshop manual instructions, buy 5 litres of fluid and expect to pump most of it through the system to get the air out. Also, at first it was impossible to floor the brake pedal before turning on the ignition (as per the book), so initially you have to turn on the ignition then push the pedal to the metal.

Needless to say, assuming your budget it enough, replace all the suspension and rack bushes while you have it apart. I also overhauled the rack and pump, but with only moderate success; better would have been to get refurbished ones. I probably should also have replaced the rack hoses; I have a small leak that might be from the hose end fittings.

Also, coat everything with anti-seize grease on reassembly, so in 20 years time when you need to do it again, it'll be easier And spray cavity wax liberally inside the new subframe.

Good luck.

[J44EAG]

I take it these are the shafts you mention.

http://www.ebay.co.uk/itm/LOWER-WISHBON ... 1c1ea76348

I agree they can be the very devil to extract! When I was in the restoration game, this job was most unpopular with the guys!

Like you, I have also experienced the bending rod home made spring compressor. Having used such a set up once, I refused to do it twice. The company then bought the right tool for the job. Tremendous relief at round and much safer too. The rod arrangement was a serious accident waiting to happen. My initiation of the rod and spacers etc was on a MK2. The uncompressed spring length was twice that of it`s length when compressed. That is a lot of spring to get out of control if something goes wrong. Doesn`t bear thinking about.

Mike

[poprivet]

Some may remember that I overhauled my front subframe a couple of years ago. The report is somewhere in these pages.. maybe.

Not difficult, but as already said a lot of work. Oh, and don't end up in hospital like I did, never did recover full use of the finger that was almost parted from the rest of my body, and I still have a slight limp from the broken leg.

But don't that let you put you off

[J44EAG]

These subframe units with diffs and other gear fitted are heavier than one would sometimes think. I remember trying to move a MK 2 diff around the workshop by myself. It appeared to be glued to the floor.

One cannot be too careful working under propped cars. Units hanging in suspension need decent support when being removed from a chassis.

Only last year I heard of a guy killed under his car. Two operators at any one time when working with heavy gear is a sensible precaution.

The trouble is that the more we do with this sort of gear, the more one is likely to have an accident due to the law of averages and complacency.

Nuff said.

Mike

[555ttg]

Well!!!!!
After reading all the replies from everyone, I was girding myself for an attempt at the subframe, but the last two replies have me wondering again, am I up to it???
My problem presently, is that I would have to remove a good subframe from a parts car I have(1985 XJ6 saloon), before tackling the XJ-S, so by the last reply, and the law of averages, I would either lose a finger or break a leg, in the XJ-S remove and refit stage........I am getting a bit worried now. Anyone want a really nice XJ-S for cheap? Needs front subframe replacing though......
Phil

[J44EAG]

Lets keep it in proportion.

Two or so good trolley jacks make all the difference. You will struggle with anything less.

In other words, let the trolleys take the strain.

Mike

[stuarthardy]

I think Phil is removing the front subframe, which is nowhere near as bad as doing the rear. It weighs a lot less.

Trick is to get the car up as high as you can on decent chassis stands and work through the instructions in the manual in a methodical manner.

Use a good trolley jack to support the subframe and lower to the ground. Withdraw the subframe on the trolley jack and dismantle on the floor or lift it onto a bench using an engine lift. The rest is easy, if a little messy. Worst part is removing the springs, which are potentially lethal if you don't use a proper spring compressor.

Don't bottle out now, you know you can do this.

Regards

[555ttg]

Thanks for that Stuart
yes, it is the front subframe I am thinking about replacing. I have a hydraulic lift in my workshop, just like they have in garages, so lifting the car high enough, is not a problem. I was trying to find out if there was any 'knack' to getting the subframe off with the least amount of bother, in as near a complete state as possible, so that I can refit another that I will have rebuilt,(if I go forward with the plan). I have several spares cars, and as I understand it, the front subframes from the saloons are interchangeable with the XJ-S, so if my spare XJ-S subframe is unserviceable, then I have about 4 saloons to choose from. If all else fails, I have a mate who has a front subframe already removed, which is sound, then all I would need to do, is build it up, and so that it is just refitting that one into the car, but I wanted any advice on the mechanics of getting the old one out first.
I hate springs removal, and have seen what a spring can do when it lets go, so I am wary of that part of the diss-assembly process. Unfortunately, being in Canada, there is no helpful tool rental section of the club out here. I am the region coordinator for Canada, and we are still 'fledgling' status at present, so unless the club will lend me the tool in Canada, then I am kind of stuck when it comes to the spring removal!
Phil

[dhdove]

I have a set of these which I use on a modern S-type.

Maybe you can buy a similar set in Canada via the internet.

I suspect, however that these may be just a little short for an XJS or XJ.

These have an advantage of being able to be cranked up with a half inch drive extension bar and ratchet.

For £3o or there abouts, they are well made and do what it says on the box. They make a useful addition to the tool kit. I`ve never had one slip or had a nasty moment with them.

http://www.google.co.uk/products/catalo ... CE0Q8wIwAA

Bigger units are of course available but come at greatly larger figures the larger you get.

Mike

MODERATORS COMMENT

The JEC do not recommend any method of front spring compression other than the approved spring compressors which are available to buy or to hire in the UK.
I do not know if these items are suitable to the job but given the price and caveats I suspect they are not.
Do not underestimate the danger of this work with the wrong kit.
I have not removed this post as I do not have sufficient info. on the suitability of these units but I would advise that these are not recommended by the JEC and SHOULD NOT BE RISKED.
DH Dove
Moderator XJS BB

[Brakebuster]

Moderators edit

This post has been removed by the moderator.

Removal of front springs BY ANY OTHER METHOD than using the approved spring compressor is extremely dangerous and has resulted in several serious injuries in the past.

Whilst members may have their own "home grown" methods, these cannot be recommended to other owners.
I appreciate that the health and safety culture may be perceived as being out of control but in this instance the danger to life and limb is too great

DH Dove
XJS BB Moderator

[555ttg]

Thanks to everybody for their kind words of encouragement.
I WILL be very careful if I do it, and will no doubt, be back for more advice.
I may do a photo series of the removal and post them here or in the mag for everybody to see.
Thanks
Phil

[Brakebuster]

i change my advice

take it to Jaguar, pay through the nose, but at least you won't get killed

BB

[Brakebuster]

Moderators edit

This post has been removed by the moderator.

Removal of front springs BY ANY OTHER METHOD than using the approved spring compressor is extremely dangerous and has resulted in several serious injuries in the past.

Whilst members may have their own "home grown" methods, these cannot be recommended to other owners.
I appreciate that the health and safety culture may be perceived as being out of control but in this instance the danger to life and limb is too great

DH Dove
XJS BB Moderator

even the right tool in the wrong hands is lethal.............................................

BB