Good Morning,

I have a 1990 xjs that is driven rarely. The rt front brake caliper stuck so i ordered and replaced the front calipers. I bled the front brakes and everything seemed normal. Good firm pedal. Heres the bad part. As soon as i pulled it out of the garage for a test drive the pedal got mushy. Then went to the floor. I have attempted to bleed the brakes again with no success. Pedal goes right to the floor. The rt front caliper is not bleeding. The left front will bleed as normal. So what did i mess up? Do i have to bleed the rear as well ? .. it is an abs sysem, any help would be greatly appreciated, my girlfriend doesnt understand my attachment to the car and is trying to get me to sell it !!!! She has never ridden in it and i know once she does she will forget about selling it. If she doesnt I would hate to have to trade her in...the girlfriend that is

Thanks
Steve

 

I have the same exact problem...How did you resolve the problem,. I bled the back brakes successfully but can't seem to bleed the front. Pedal goes all the way down.
The front section of the reservoir still has dirty fluid. There is no filler cap on the front section

 

mara52,

You haven't said what year XJS you've got. It makes a big difference as there are 3 different braking systems over the years that operate in completely different manners.

I'd suggest that you start a new thread and explain the background and the current problem. Also, if you've got dirty fluid in the reservoir, I definitely wouldn't start by bleeding the brakes. I would start by trying to syphon out as much of the old dirty fluid first from the reservoir and then refilling with clean fluid before you start anything. If you have a Teves II brake system (c1989 - 1994), you really don't want to be flushing dirty fluid through the system.

Cheers

Paul

 

Hi Paul,
My Jaguar is a 1993 XJS 4.0 6 cylinder. Yes the first thing I did was to siphon out all of the dirty fluid, but only the rear chamber was emptied. I could ;not figure out how to empty the front chamber. I bleed the back brakes properly using the correct procedure using the brake pump by turning on the ignition when called for.
The front chamber still has dirty fluid.
Then I bled the front brakes in the conventional manner without turning on the ignition. I only got a couple of ounces out of the right side, but none out of the left side.
Now my two front calipers are grabbing the rotors and will not allow the wheels to move. Also the brake pedal now goes down to the floor. I cannot seem to bleed the front wheels. What if anything did I do wrong?
Where are you located?
Thank you,
Frank in Florida

 

Frank,

I assume the brakes were working fine before you started the flush and bleed procedure?

If so, when you finished bleeding the rear brakes, was the pedal firm, or did it go to the floor then?

I would go back to the beginning.

- Start by carefully bleeding the low pressure side of the system
- Then bleed the rear brakes again. Is the pedal "normal" at the end of that procedure?

If the front brakes are stuck, DO NOT try and push back the pads / pistons, unless you have opened the bleed nipple on the caliper and attached a pipe to capture the fluid that is expelled when you push back the caliper pistons. Do not allow the fluid to go back up the pipe to the ABS valve block.

Much as I'd love to come and help you, I'm in the UK as my status shows on the posts, so sadly that's not practical!

Cheers

Paul

 

Hi Guys

Sorry to hear you are having Braking Problems

But if you've got any 'Crud' in the Reservoir, then it may be easier just to take the Reservoir Off and then once having done so Wash it out and then dry it off as even Microscopic Pieces of Crud pushed back the wrong way (as Paul Ptjs) has already mentioned, can really do some damage to the Master Cylinder Actuator

Taking the Reservoir off is fairly easy, although even when you think the Reservoirs empty, there will still be lots of Brake Fluid inside, so prepare yourself for Brake Fluid running out everywhere and don't let it get near the Paintwork or it will Strip it off!

So have lots of Soapy Water Standing by, although it may be even easier to take the Master Cylinder Actuator and The Reservoir out in one Piece, without the need to remove the Reservoir first

It's not a big job, there are only Four Bolts and you don't even need to disconnect the Brake Pedal

Providing that your System, is the same as mine

Just don't undo the Valve Block that is Bolted on the Side, as lots of Bits and Pieces including all the Valves can fall out of this under their own weight and also break the Ribbon Connectors, so do not even be tempted to Tamper with this, or you could end up with an even Bigger Problem to sort out

Removing the Brake Reservoir and the Brake Master Cylinder Actuator in one piece

 

Try to find out where the problem is. I would use line clamps and the three flexible hoses. The pedal should be rock hard. Release each clamp (do one, clamp it again, and do a another). When you release one and the pedal is soft, you can trace it down,

 

(1) Ignition OFF throughout the process

(2) Do not Allow the Reservoir to Run Dry, or you will have to Start all over again!

(3) Do Not Touch the Brake Pedal

(4) Essentially what you are doing, is to let (Brake Fluid) Flow down to the Brake Pump under Gravity alone (Ignition Off and don't touch the Brake Pedal)

(5) In order to release any Air Bubbles Trapped in the Pipe from the Reservoir to the Brake Pump, this is what you need to do

(6) Pull out the Spring Pin where it goes into the Brake Pump (Marked with a Splodge of Red Paint) 'Easy and So Far So Good' Now comes the 'Tricky Part'

Where you pulled the Pin Out, you will see a Piece of Braided Flexy Brake Pipe about 6 ins Long and on the End Nearest the Brake Pump, you will see a Plastic Elbow that goes into the Brake Pump itself

Ideally you need to very Carefully Rock and Pull that Plastic Elbow out of the Brake Pump without Breaking it, as unless its been removed before, then it won't want to come out, as the 'O' Rings on the End that goes into the Brake Pump are holding it fast after about 20+ Years or so (Copious amounts of WD may help)

Sometimes it comes out easy and sometimes not Just be Careful Not to Break the Plastic Elbow!

In the event you may lose your Nerve (Plan 'B' is to Pull and Jiggle) the Braided Pipe Off the Elbow

Where as soon as you do this, Brake Fluid will come pouring out of the Open End of the Elbow or out of the Tube you Pulled off

So have Plenty of Rag standing by to mop up any Spills and also Soapy Water to Sluice off any Brake Fluid and don't let it get on the Paint Work or it will Strip it off!

Also have a Jar to Catch the Brake Fluid as it pours out or else make a Channel out of Tin Foil

At this Point there maybe a tendency to Panic a little bit but this Brake Fluid is Not Under Pressure, so if you want to Stop the Flow, then just put your Finger over the end of the Elbow or Pipe that the Fluid it pouring out of

If the Brake Fluid is pouring out then this is exactly what you want to happen, as this will displace the Air Trapped in the System as it does so and should only take a Few Seconds until it runs Clear of any Air Bubbles

Then and This is MOST IMPORTANT Put the Plastic Elbow back into the Brake Pump while Brake Fluid is still pouring out of it!

In other words you are doing it 'On The Fly'

If you miss the Vital Step of Bleeding the 'Low Pressure Side of the System' then you may not be able to ever get the Hard Pedal that you are looking for

Then you can Put the Spring Clip Back to Secure the Plastic Elbow in Place as it was before

Congratulations! That's the Worst Part over

Then you Can Bleed the Brakes as Paul (ptjs) has described

Don't do this the way they describe it in the Manual (Do it Paul's Way!)







If you really get stuck on this then you can read through an early Post of mine that describes it in a Bit More detail where I probably made it sound a lot more Scary to do than it actually was

Bleeding the Low Pressure Side of the Teves Brake System