I would err on the side of caution with Doug's method, whilst I don't doubt it can work those lower wishbones don't push vertically the spring is not compressed evenly along the vertical axis so there is force in play aided by the pivot on the wishbone to push toward the centre of the car - if you don't get that weight and the jack very well secured and positioned that spring is escaping - and you will be very close to the event - and don't for a second think you aren't going to need to get a little rough to separate things.

You get nailed by that spring and it will be at the minimum a life lesson, there's more than enough energy stored in it whilst compressed to dispatch you and keep going.

 

My method will not work with engine out.

You need the weight to keep the spring compressed.

Doug

 

As i mentioned just above, you need the engine IN the car.

The lower control arm can't go anywhere as it is ties to the cross member on the inside. The upper subframe pocket the spring seats into is fixed.

The spring can't go anywhere as neither seat, top or bottom, is movable in/out or side/side. The lower can only go up/down, and with a jack under there, and engine weight keeping it compressed, it isn't going to move. Rest the lower on a jack stand, and you don't have to worry about jack failure.

There is nothing sketchy about it. If you are paranoid about anything, fasten the spring with a cable and clamp to the hole in the lower CA thru the center hole

Doug

 

Using a hydraulic floor jack under the spring plate as Doug suggested is an entirely acceptable and safe way to proceed.

do 1 at a time, with car on the ground(on its tires, not jack stands obviously)and you don't have to worry.

 

I agree; have done it many times on various cars. And I'm one of the people who still gets a little nervous dealing with springs.

Cheers
DD

 

The jaguar repair manual (PDF) lower ball joint replace section does specify put car on jack stands and floor jack under spring plate.
At this point I'm trying to get myself from scared into inaction as I've never done this job on any car before... to pick a method and proceeding with caution.
Overall I am down to hoses, wires and fluids (and rebuilding master cylinder... started leaking from the plastic elbows when I started bleeding brakes grrrr)

 

The spring plate really does make spring removal/install safe, compared to other cars where the entire lower control arm is flopping around during R&R.

Doug