Hang on a minute!

Are those triangular fittings free floating & not fixed? If so they should just slide out of the way, yes?

 

They are floating, and I once had a pair come loose on me when out in the car. A local tyre and battery shop put the car up on ramps and bolted them up. I think it's best to have a second nut on each bolt as a lock nut or else use steel, NOT Nyloc, locking nuts

 

I have a tip to release the rear resonators from the pipe in the IRS cage.

One was not too bad after soaking with Liquid Spanner & twisting the S-pipe.

T'other was a swine! Heating to cherry red & soaking did nothing.

But it responded to a big Stilson i.e. a plumber's pipe wrench. With the good grip & leverage, I was able to get the resonator to twist & off it came.

Can anyone offer tips on re-attaching the hanger nearest the S-pipe? I'm considering replacing the rear resonators with plain pipe

 

I dont know if you still have the need for heat , but Bunnings sell a
Hot Devil Super Oxy Blow Torch Kit with Fuel & Oxygen Gauges for the $155 mark
save renting from BOC gasses
Bob

 

Bob!

Mate I have one & it's next to useless.

For a start it's oxygen & propane and it doesn't get hot enough to even melt brazing sticks!

I've just gone back to BOC for oxy-acetylene. I've discovered that if I go to a major, dedicated BOC agent they ALWAYS have great deals. I got small oxygen & acetylene for $79 & $108 and that was for contents AND a year's rental of tanks. And the tanks are 10+ times the size of the Bunnings kit. I can afford that. Before, I was going to a tool place that had gas as a side line & was paying thru the nose.

 

No problems ,
With these hot devils dont use the propane blue bottle use the Mapgas instead thats the yellow bottle a lot hotter
but all good now you have got the real deal
Good luck with the bleeders , a real mongrel job
Bob

 

I've always regarded Spare Parts Catalogues as far more helpful than Workshop Manuals & I just had my thoughts reinforced again!
When I received a screen shot of the rear suspension I saw that the lower shock mountings are done via a single long pin with threaded ends. It was then obvious how to proceed:
1. Remove the nut & washer on both lower shock mounts & swing the spring/shock assemblies aside.
2. Attach a vice grip to the exposed pin
3. Attach a nut to one end (to protect the threads) & hit the nut with a hammer while twisting the vice grip. Finish the job with a punch just smaller than the pin diameter
The pin drifted out very easily.
The radius arm mounting bolt will now slip out with the hexagon cut off only just clearing the stump- it was the proverbial bee's knee of clearance!

The only hang up is that the spring was under slight tension & so the unit got longer when free of the pin so a spring compressor will need to be deployed to reattach the spring/shock units

 

We have direct evidence of rusted up callipers & blocked rubber hoses.

Is this valve susceptible as well?

Can it be dismantled & cleaned?

Edit: OK it's NOT an equaliser it's a differential valve. My bad.

 

We've been advised by a knowledgeable Jaguar workshop to leave the differential valve alone unless the rear brakes are locking up under heavy braking.

We have decided to replace the rear discs while the IRS is on the bench. Holey Moley are those bolts tight!! Any hints on how to detach them without rounding off the inboard bolt heads?

Also I'd expect that the outer uni-joints are of the constant velocity type because when the swing arm goes up & down, the length of the drive shaft has to change. Will the drive shaft move out enough to detach the disc from the diff hub?

Lastly, can the disc mounting bolts be extracted from the drive hub? There doesn't seem to be enough clearance for them to come out. If/when they do come out I'm going to use new bolts with a bit of square rod welded to the heads (making a "T" head) so that they lock without the need of a spanner

 

Yes, the breather pipe coming out of the differential cover needs to stay.

You shouldn't be trying to loosen those 4 bolts by turning the bolt head (inboard). Use an appropriate box-end spanner to hold the head and loosen by turning the outboard nut.

The half-shaft is the upper "swing arm" of the suspension, it does not change length. There are shims at the inner u-joint/brake disc that allow you to set the camber, keep track of them when you disassemble so that they go back in the same place. It would be worth the effort to check the camber as you reassemble to meet specs. The half-shaft will clear the disc bolts when the outer hub-carrier is allowed to swing out/down, pivioting on the lower/outer fulcrum arm joint.

If I remember correctly, there is one spot on the output shaft carrier that will allow you to wiggle the bolts out. If you are determined to remove those 4 bolts, I think it's a little easier once the brake disc is removed, gives a tiny bit more wobble to the bolt. If you replace the bolts, make sure you use the same grade as the factory bolts/nuts.

Dave

 

There are no constant velocity joints anywhere on the suspension, they are all the traditional Hooks joints. The rear drive shaft forms the upper arm of the suspension, with the lower arm doing most of the work with its widely spaced inner and outer bearings, and being kept in place by the trailing arms. It's a very elegant design, and was in use in Jaguars from 1961 onwards with the E-type and Mark 10, only ceasing when the XJS left production in the 90s. Ride quality of Jaguars was superb with it, and the later designs, whilst good, never matched the Magic Carpet ride.

 

Well, thanks for that. I now see that with a DOUBLE jointed driveshaft a C/V joint would be superfluous.

Back onto the topic, I have discovered that when the uni joint on the disc is disconnected, the wishbone swings down & pulls the joint away giving clearance to remove the disc. *Thanks Dave!*

BUT, as the photo shows, the disc fouls the longitudinal arm of the wishbone and won't detach unless:

(a) the bolts are removed *Dave, can you please elaborate. AND the bolts are stuck fast. More heat required??*

(b) the wishbone pin is driven out and the wishbone slid forward to create more clearance.

Which way do I go?

 

Isn't funny when you write down what the problem is & you suddenly see the solution

By getting the IRS cage upside down you can pivot the swing arm out of the way & the disc comes off.

I'm happy to say we have stopped going backwards & can start to go forward

 

Those are the lessons learned that stick with you for life. Good luck.

Dave

 

The work continues slowly but steadily.

With the IRS on the bench, I have lubed all the grease nipples bar 2: both the outer swivel link pins on the rear hubs.

I cannot get grease thru and I'm using a MacNaught air powered grease gun. I've put new nipples in and have poked the holes with wire and given it plenty of heat via my oxy acetylene torch to no avail.

The housing is alloy so the link pins must be swivelling in brass (?) bushes, yes? Am I correct in assuming that the bushes have a hole that lines up to the grease nipple hole?

Do the bushes have a history of twisting such that the holes no longer line up so that pushing grease in via the nipple can't get thru any more?

 

The outer hub/fulcrum arm has tapered roller bearings, not brass bushes. The grease nipple in the middle of the outer hub casting pumps the cavity full of grease and eventually through the roller bearing. There isn't anything inside the casting that would block grease as the cross pin (big bolt) has plenty of clearance in the cavity. I wouldn't get carried away with using heat, there are seals outside of the roller bearings that could be damaged. If you have replaced the zerk fitting and still can't pump grease, the only thing I can think of is the cavity is already full and the grease is trying to flow through the bearings and pushing against the seal, all of which is held snugly in place by the fulcrum yoke. Look closely at the hub/outer yoke joint to see if a small amount of grease is escaping there. Also notice if the hub/yoke pin might be turning in the yoke (shiny area on yoke, no dirt caked around nuts, etc), if it looks like this might be happening, big trouble. The bearings might be rusted/seized to the pin and causing the pin to turn instead of remain stationary. I think this is unlikely.

Here is a picture of the bearing(s) in the outer hub.




Lower outer fulcrum pin through outer hub.

 

Thank you!
That explains a lot and is a big relief.
I was expecting grease to come out of the ends of the pins like one would get when greasing king pins etc. But, as you have explained, the seals will stop this happening!.
You are quite correct in that I get a small amount of grease leaking out so it appears all is OK

 

Well after literally decades of frustration getting these damn things to start I think I have discovered a way to get them to go on 1st time every time.

Two open ended spanners, 1 small one to fit over the pipe ( I used an 8mm), one for the hex head on the fitting usually a 7/16AF

Make sure the fitting is absolutely perpendicular to the hole.

Use the 8mm spanner to push the fitting firmly into the hole & turn the hex with the 7/16

Worked magnificently for the cross pipes on the rear callipers. At one stage, I considered removing the callipers to put the pipes on!

 

It would appear they DO provide an outlet for XS grease.
There is a breather (?) directly in line with the grease nipple on the other side of the assembly.
I only saw it when I flipped the IRS unit to replace the hand brake callipers. There must have been ~200 grams of grease piled up there!

 

The manual says it's possible to remove/refit the hand (parking) brake callipers with the main callipers in situ.

I can't see how to get them to do so. I can't get them to slot into place. I can get them over the disc via the big hole in the frame but they foul the IRS cage when I try to move them around the disc & line up the mounting holes on the main callipers.

What am I doing wrong?? A photo would be fantastic!