JigJag, I agree about rebuilding the Master Cylinder. Can you or anyone reading this post point me in the right direction for finding the Rebuild Kit?
If you have a Company Name or a Link to a website please let me know. Much appreciated!
Tom

 

Jaguar has a classic parts division, for cars older than 10 years. The XJS braking section is here: https://www.jaguarclassicparts.com/u...-and-reservoir

I think you want part #1, which unfortunately looks no longer available. SNG Barratt is my favourite vendor and it appears a seal kit is not available either.

The nice thing it's it's all genuine parts and the exploded diagrams and very useful.

Also watch for VIN changes, the system after VIN 198334 (last 6 digits of the car's serial number) is very different to the previous system.

 

 

JigJag, I followed your LINK (LMGTFY), Google is a great way to search and I find myself there almost everyday because the Internet is a great tool. I posted the request here at JaguarForums because being a member of a forum often returns better results than Google. As you can see from this Thread many Jaguar enthusiasts have taken the time to share their experiences and help me solve my brake issue.
My VIN 190954 at jaguarclassicparts has limited parts. Looks like I will continue the search.
Thanks for your post,
Tom

 

You're right! My VIN: 190954

 

A bit pricey !! but they seem to have one:
1990-94 Jaguar Brake Master Actuator LHD JLM1475

 

Hi Jagboi

The Instructions that you posted are for a Car with a Teves Mk111 Master Cylinder Actuator and while I am quite prepared to wind up with egg on my face here

On a 94 the OP should have the Later ABS System with the Vacuum Servo on one side and a separate ABS Motor on the other side of the Car, as in the Photos below

 

Hi Tom

On the assumption that your Car has the later Braking System as in the Photo below and you are looking for a Seal Kit that is NLA

You could always consider fitting a New Master Cylinder from an XJ6 which probably wouldn't cost a lot more than a Seal Kit if only you could buy one as they are NLA

SNG Barratt.Com do a Brand New Master Cylinder (Aftermarket) for an XJ6 Part Number JHP 807 for £94-20 which in your current situation

(where you can't find a Seal Kit) seems like a bit of a Bargain

As you also don't have all the hassle of rebuilding it

But before you go and Splash your Cash

I would have a word with your Jaguar Guy, to make sure that it would fit









This looks like the Brake System you should have on your 1994 XJS

 

Hi Greg, Thanks for the link. I actually had that website bookmarked from my research. Yes, it does seem pricey. I would prefer to find the rebuild kit but haven't found one yet that matches my VIN 190954.
Tom

 

Hello "OB", I appreciate your taking the time to upload the photos.
My 1994 XJS 4L 2+2 is different from your verhicle. My Master Cylinder/ABS is an all-in-one assembly as shown in the photo.
It's available at this LINK but if possible I would like to do the rebuild with a kit.
Apparently during the production of your Jaguar the switch was made to the newer Master Cylinder.
My VIN 190954
Thanks,
Tom

 

The change was at the 1995.25 model year, VIN 198334. OP's VIN is 190951. The 1994 model year started at 190528

 

Hi Tom

Then it looks like you have the Teves Mk111 Master Cylinder Actuator the same as my Pre-Facelift XJS's



Teves Mk111 Master Cylinder Actuator on 'Cherry Blossom'


If your Pedal is going right down to the Floor, then it sounds as if the Low Pressure Side of the System might need Bleeding as per Jagboi's pages from the Manual

This is how I Bled the Low Pressure Side of the System on my Car 'Cherry Blossom'

Bleeding the Low Pressure Side of the Teves Mk111 Master Cylinder Actuator System

The Next Link is Repairing the Teves Mk111 Master Cylinder Actuator, where the most Common Problem, is a Broken Ribbon Wire which Prevents a Valve from opening and is an easy fix but in the Interests of Safety needs to be done by a Professional Soldering Shop

Repairing the Teves Mk111 Master Cylinder Actuator

 

One way to check the master is to use line clamps on the flexible hoses. With the clamps in place, the pedal should be rock hard. If it is, you're master is ok, if not, replace/rebuild the master.
If the master is ok, remove the line clamps one at a time and see which one will cause the problem and go from there.

 

Hello "OB",
I devoted today to do research on the Internet and to call different companies and ask questions. Everyone here at the forum has been helpful, much appreciated.
Looking at your photos I'm not absolutely sure we have the same Teves Master Cylinder. The Internet leads me to believe that I do have the MK111 version. I've read many of your posts here and see that you've tackled issues with your car that most people would run from. My mechanic in Greensboro, NC talked with me for about 45 mins on the phone today. He lives and breathes Jaguars so he was my first phone call today to pick his brain. He is willing to remove my Teves and send it out to be rebuilt but he gave me a few suggestions to first try. My local mechanic here in the NC mtns is not well versed with Jaguars so I haven't made any decisions yet on how to move forward to resolve the breaking issue. I suspect that bleeding the brakes will restore them to normal but this doesn't fix the problem permanently. I'm 3.5 hrs from Greensboro, NC so I would like to feel good about driving my car that far.
Here's a post from a different forum that you may find interesting. It rambles and it's a long post but I do think I will try the "gravel" solution and see what that may do. Basically I will need to drive the car on gravel or a slick surface and apply the brakes to activate the ABS function. This will force the piston to move (it may be stuck) and this will push the fluid and any dirt or residue out of the way. It's worth a try but there's no way to know if anything has changed. The car in the post has my same car model and the owner has a similar brake failure problem.
The Charlotte, NC Jaguar Dealership said that would do a diagnostic on the Master Cylinder but I have my doubts that they will find anything. Likely I will end up paying for a lot of new things that really don't need replacing.
There's a Brake shop in Canada that will rebuild the Teves for $300 and they said they have all the parts to do the rebuild.
There were at least 5 shops throughout the United States that said they would not touch an ABS Jaguar Master Cylinder. Just too complicated to rebuild.
I'm waiting for two call backs from very qualified companies that apparently do what the Canadian company does.
After many conversations with many specialists all day we all conclude that there are flaws in the Teves Master Cylinder. Some mechanics prefer to do a retrofit which eliminates the ABS function thus taking the braking system to a simple reliable Master Cylinder system. (Expensive)
Allowing my model Jaguar to sit for a lengthy time is not a good thing. The Teves wants to stay active to avoid residue and internal corrosion.
My Dot4 Brake Fluid is one year old now and I drive my car regularly except in the Winter months to avoid the salt on the road.
I'll spend some time on the phone tomorrow but plan to go ahead and do the bleed soon.
Tom

 

I think it's important to mention that this car was purchased out of a private collection of 15 classic cars. It was disclosed to me that the car had not been started in 2 years. The collector reached a point in his life where he no longer focused on his collection and his family decided to sell everything. There were three Jaguars and I bought one of them. My current brake problem may be related to the long period of time the car was not maintained properly. It was garaged and kept dry but none of the cars were driven regularly.

 

Hi Tom

I'm not sure the 'Gravel Option' is a good idea but only you can decide

As for me I am going to do a Retro Fit of the Simple Vacuum Non ABS Master Cylinder System that you mentioned on my other Car 'The Ice Princess'

And would have had this done and dusted by now, were it not for a Broken Bleed Nipple in one of the Rear Calipers, which will unfortunately mean taking out the Cage

So that is going to be a job I am pencilling in for next spring but in any event please let us know how you get on

 

Hello "OB",
Little by little I hope to make some progress. There are been multiple forums talking about the "gravel" option which would hopefully loosen up any stuck pistons. I rarely have to hit the brakes hard on a slippery surface but this is where the ABS would stabilize the event.

I have not been able to locate the "kit" for the Teves rebuild. Since my Master Cylinder is not leaking I don't really think it needs to be rebuilt. Just hard to say what might be the problem. Have you had any trouble with your Accumulator? Could this be a potential problem for my braking system?

I did get a quote for a Master Cylinder from British Parts UK. The USA quotes are considerably less expensive.

 

Hi Tom

The Accumulator could have bearing on it but I have no idea how to test it, although as far as I know if it goes down then it could result in a hard pedal

I've had trouble with the Brakes on all my XJS's except my 1995 which is fitted with the later Teves System with the ABS unit on the opposite end of the Firewall

But the Best one of all is one on my very early XJS Coupe that has the Vacuum System with no ABS which so far has never gone wrong, no doubt due to its Simplicity

Where in total contrast, I've had a lot of problems with the Teves Mk111 Master Cylinder Actuator, which were all very easily fixed by rewiring the Valves inside the Valve Block

The Valves inside the Valve Block on the Side of the Master Cylinder Actuator, were originally wired up with Ribbon Connectors, just like you might find inside a TV

But with the Heat and Vibration, these Ribbon Connectors can and do go 'Crispy' over time and can break off without warning, which can result in your XJS taking a violent dive to the Side of the road

But once rewired with High Temp wire, the problem was quickly sorted out and everything worked as normal

So in your case the very first thing I would do, would be to replace the Caliper on the other side and then you would be able to take that right out of the mix

Then refill and re-bleed the System including the low pressure side, as that's the one that if not done can have the Pedal going all the way down to the Floor (who knows that might fix it and be all you need to do)

If you still have a problem after doing that, then I would take out the Master Cylinder Actuator in one piece
(only 4 bolts and easy done in an hour) Then take the Valve Block Cover off and have a look to see if a Wire is Broken

Then either fix it or get one from a Scrapyard/Breakers, a lot depending on just how much money you want to spend

 

Hello "OB",
Thanks for the heads-up regarding the ribbon wire.
Tom

 

Hi Tom

I've just come across a short Video that I made some time ago about Testing the Valves in the Valve Block of the Teves Mk111 ABS Master Cylinder Actuator, that I thought might be useful in your situation

The following Photo will show you what is inside the Valve Block including those 'Ribbon Connectors' together with the Video that shows you how to Test it

Just a word of Caution: If you turned that Valve Block upside down then its highly likely that some of those Valves would fall out, where the weight of these alone could be more than enough to break those very fragile 'Ribbon Connectors'




What's inside the Valve Block of the Teves Mk111 Master Cylinder Actuator

Testing the Valves in the Valve Block of the Teves Mk111 Master Cylinder Actuator