Ball joint shot on lower control arm of by left front wheel. Purchased replacement arm instead of popping out ball joint. Jaguar Workshop Manual has step in replacing this arm disconnecting top ball joint. Can't see the need.

 

It's been over a decade since I did suspension work as routine repair but I think I just put the long spring compression rod in place and tightened a few turns to hold the spring.
Removed the inner fulcrum bolt (after marking the camber adjustment setting), remove the ball joint nut, displaced the taper from the vertical link, removed the fasteners from the spring plate and damper then withdrew the arm.

Leave the spring, plate and forward arm alone!!!!

I might have forgotten a step?

 

Endorsement of what Bob MCM mentioned above. His experience helped me out in the past.
Rear lower arm/ball joint (and front lower arm if you wish) can be replaced without removing the spring.
Fashion some 3/4” treaded rod about 15” long per the attached pic. For the top pin I used a section of an Allen wrench. Being high tensile the diameter can be reduced without compromising the threaded rod. For additional security place a jack under the spring plate as well. Just do one arm at a time.

 

+1 to what motorcarman said. Only additional steps, you need to lower the steering rack to be able to remove the rearward LCA's adjustment/pivot bolt. You can do this carefully without touching the fluid lines by doing all the other LCA steps (hardware removing, removing the nut on the pivot bolt, etc) then undoing the 4 steering rack mounting screws and lowering it slightly, just to pull the bolt out, and then reinstalling it. I don't remember, you probably need to undo the lower steering column from the rack before lowering it. If replacing both side rearward LCA's, just remount the steering rack loosely by 1 screw on each bracket before moving to the other side.

 

Thanks, already picked up parts to built it.

 

The Jaguar factory tool has a 5/16" (8mm) heavy roll pin in the top of the threaded rod to hold it in the slot. (V notch)

 

With the cheap ready rod I was not comfortable with a 5/16” hole through it. The sawn off Allen key I used was 1/4” and worked well.
If doing it again I might use solid bar threaded at the lower end, or modify a long bolt.

 

The factory tool is 20mm, NOT 3/4' (19mm) so the parts are slightly different.
I have a factory tool as well as a pair of 3/4" all-thread rod tools so I know what you are talking about.

 

Replacement went smooth. Jag Manual has many unnecessary steps. Removed three bolts on rack and left right upper bolt in. This allowed rack to pivot and withdraw arm bolt.
I used a combo of the 3/4 in threaded rod and M10 guide rods. Coil springs scare me. I’d back all the nuts on the M10s by hand an inch away from the plate and them lower the 3/4 in rod and repeat. M10 rods never under load. Just wanted there if 3/4 failed.

 

Bob, i'm planning to do lower arm bushes on mine and just want to be absolutely sure that i understand "Leave the spring, plate and forward arm alone" part well, does it mean leaving >compressed< spring in place? it would certainly make job easier, also, doesn't compressed spring impede aligning fulcrum bolt at reassembly?

 

Leave the front lower arm attached to the spring seat with the compressed spring in place.
Remove the ball joint nut and separate the vertical link.
Remove rear fulcrum bolt nut then unbolt the spring plate from the arm.
Slide the arm out of the suspension for work/repair/replace.

Install arm on spring plate loosely and install fulcrum and ball joint into vertical link.
Tighten the bolts and then work on the front lower arm if the bushes need replacement. (same basic procedure)

There were superseded bushes and TSBs for the lower control arm bushes and I did DOZENS and DOZENS of inner bushes!!!!!!!!

 

In such ccase the whole job looks doable compared to decompressing spring and having everything apart, that's good news.