This started a few weeks ago, and has progressively gotten worse. When I hit the brakes it is now pulling left pretty hard, depending on how hard I hit the brakes. I'll start by examining the pads and rotors, possibly bleeding.....

Any Ideas would be appreciated.

Thanks...Jimmy

 

Hi Jimmy

Please could you say what Year and Model of XJS you have that problem on

 

Thanks Orangeblossom....my car is described in my post signature, with picture.

 

Pulling to the left would suggest the front right caliper isn't working properly. Either not at all or to a low degree. Can be a sticky piston, a collapsed hose or if ABS a non working connection...

Take the front right wheel off and check for function. Or head to a local brake balance tester and check.

 

 

Hi Jimmy

Your Signature is not showing up

Do you have this type of ABS Brake Master Cylinder Actuator in your Car (see photo)

 

Hi Jimmy

From the way you have described the symptoms of your Car pulling to the left and getting 'Progressively Worse'

It doesn't sound like a problem with the Brake Master Cylinder Actuator (although it could be) and even if it is it's really

Not much of a problem to sort out (in the Scheme of things)

If there is a Failure in the Valve Block of the Brake Master Cylinder Actuator it usually an all or nothing type of situation

Where you could be 'Sailing along without a care in the World' then as you go to hit the Brakes

The Car might unexpectedly pull to one side of the road

And try and ****** the Steering Wheel right out of your hand

Rather than Progressively get worse over time

It could be a Stuck Caliper as 'Daim' already mentioned but equally could be a Sticking Brake Pad

Because contrary to belief Brake Pads are not always a 'Perfect Fit Out of the Box'

As Tolerances can vary depending on where they are made

Especially in the case of some After-market Pattern Parts on which I have encountered this problem many times

Where as the 'Material' starts to wear down the Metal Sides of the Brake Pads get jammed up in the holder

where they Slide into the Caliper

Ideally the Brake Pads should be a really nice fit so you can slide them in or out by holding them between your finger and thumb

If you need a FBH and a FB Chisel to get them out like I did then you've obviously got a problem with them sticking

Although that didn't seem to be apparent at the time I fitted them from New

So whenever I fit New Brake Pads, if they seem a bit to tight going in, then I get out the Angle Grinder with a Sanding Disc on

And then Shave a few thou off the sides of the Metal Edges of the Brake Pad

So they slide in and out nice and easy just holding them between my finger and thumb

You can see how I did this myself (with photos) on Page: 9 of my 'Cherry Blossom' Restoration Thread

And here is the Link to that Page: https://www.jaguarforums.com/forum/x...-122634/page9/

 

Hi!
Your problem could be a cracked, worn brake hose.
It will bulge or balloon out when pressure is applied will not
apply pressure to the right caliper. Or your right caliper needs
renewal.

P O R - Press On Regardless

 

I'd start by checking the sliders on the caliper are not siezed first.
Remove the pads and you should be able to move the caliper back and forth freely, if you cant then the sliders are full of crap and need taking out, cleaning and greasing.

 

AFAICS we still do not know that model or year. The calipers, on pre facelifts anyway, do not have sliders; they are the piston each side type.

 

The 'could be' list includes many possibilities but my money is on a RF caliper, probably seized, going along for the ride while all the others do all the work. So, I'd begin with inspection of the caliper.....and be prepared to go further. Depending on history, mileage, and prior care it wouldn't be unexpected to discover several areas needing attention on a 24 year old car.

(I this scenario it doesn't take much to nudge me into a 'do it all, do it once, do it right' frame of mind and just press on with a well deserved system overhaul. But, spending other peoples' money is always easy )

The XJS always had fixed calipers...except the rear calipers of outboard brake cars, which were sliding type

Cheers
DD

 

Don't forget to check the rear calipers as well. I have seen a bad rear caliper cause the car to pull.

 

I had exactly the same and it was a collapsed hose on the right hand front caliper; new, braided hoses and a full bleed and the problem went away.

 

I want to thank all of you for your responses.
I didn't realize that my car description and signature wasn't showing up.
The car is a 94, 2+2, V12.
I'll tear into it this weekend, and let you know the results.

Thanks Again for all the suggestions.....Jimmy

 

Hi Jimmy

Uneven Brake Pad wear would be a Clue to a Sticking Piston in one of the Calipers or a Sticking Brake Pad, where it slides into the Caliper

Be very Careful Not to Push the Caliper Piston back into the Caliper, without having the Bleed Nipple Open

As if Brake Fluid is sent the wrong way up the Brake Pipe into the Brake Master Cylinder Actuator

It can damage or block the Valves in the Valve Block

And leave you with an even bigger problem to sort out, if your Brake Master Cylinder Actuator is the same as mine



The Brake Master Cylinder Actuator on my 1990 XJS

 

A 1994 should have the very late XJ40/X300 ABS with a pump and block integrated into one unit. More reliable and they work with a brake servo. So if the vin ends with a higher number than 179737, then the ABS unit is different.

 

My VIN ends in 194328.

 

Thanks O.B.
It does look the same. It even has the same dead bug on top!

Cheers...Jimmy

 

Hi Jimmy

Since it appears that your Brake Master Cylinder Actuator is the same as mine, then you need to be careful that you don't send Brake Fluid the Wrong way up the System

As any microscopic particles of crud could block up one or more of the Valves although it could get even worse than that

For if you or the previous owner haven't changed the Brake Fluid on a regular basis, then Water in the Brake Fluid can block the Valves with Rust

If you don't like watching 'Horror Films' then you may want to look through your Fingers or hide behind the Sofa before viewing the following Photo: (You have been Warned!)



Rusty Valves in the Valve Block of a Brake Master Cylinder Actuator of an XJS



This Valve from the Valve Block of the Brake Master Cylinder Actuator was completely Blocked with Rust

This Valve Block was off the Brake Master Cylinder Actuator of my Car 'Cherry Blossom' which had only done 25,000 Miles from New!

Mind you She had been standing outside unused for 14 years which certainly didn't help!

And you were thinking 'Alien' was Scary!

Hopefully yours will be ok but one Blocked Valve can be enough to have your Car pull left or right without any warning, as it tries to ****** the Wheel out of your hand

So just a little something for you to keep in mind, in case you might get tempted to lever the Caliper Pistons back without leaving the Bleed Nipple open!

Just as bad could be a Broken Wire inside the Valve Block of the Brake Master Cylinder Actuator, which again could have your Car pull to the left or right

But try not to get Paranoid about it, as its a fairly easy fix 'in the scheme of things' which will just cost you a couple of bucks to sort out

So lets not even go there for the Moment until at least you have made sure that your Calipers and Brake Pads are not Sticking

 

My 1995 XJS Vin # SAJNX2740SC198197 also pulls to the left when braking. It's quite a pull but it doesn't take a lot of effort to hold the steering wheel to keep it straight. I already replaced the front calipers pads and rotors and the system seemed to bleed ok so I am thinking the hoses are ok but maybe you don't see the hose issue when bleeding? I also swapped sides of the front wheels so it's not the tires. From this thread I have noted to check the suspension bushing and rear calipers...and maybe the hoses? Plus possibly, now the valve block. I think one of those is about $1800 if I remember correctly if I have to replace it. Could it be a steering issue? Although it seems to go straight under normal driving when I let go the wheel.

Appreciate any feedback/ on how to best narrow it down other wise I guess i'll replace parts from cheapest to expensive order.

sorry, forgot to say it's 2+2 IL4