MatraSport Forum

When applying the brakes the car always stopped on a dime, as they say "over there". But holding the pedal down I noticed that after a few minutes I could push it down further. Leting go and applying it again brought the pedal bck up. >:(

Conclusion, worn piston seals.  :(

So I got a new set from Simons (partnumber 13019A at 20€) and installed them this past weekend. In the process I overhauled the cylinder itself. Cleaned off all paint, brushed away all rust, honed the inside, rinsed, painted with 99,9% zink, followed by a rally black coat. Cut away old seals and installed new ones (eased by the supplied mounting fluid in the kit)

The result is a firm pedal, that stays where it is at, once applied. :D

A note of interest for you who are faced with this job.
When disassembling the master cylinder, you have to remove 2 cotter pins that hold the two pistons in place. It turns out that there is a hole in each end of the pin. this is handy, as you can insert a small hook and just pull them out. They are not seated very firmly.

As allways, very nice to see, this will be a job for me over the winter so all the advise would be greatly appreciated

Hi david.
I just modified my post to include the Simons partnumber for the repair kit.
Best regards.
Jon.

I am not a big fan of reviving brake master cylinders this way.
My experiences are not so good, and with my mini's in the past it didn't last very long.
Most of the time the water in the brakefluid pitted the cylinders to much.
With a bit of searching you can find brake master cylinders for low prices.
This one I bought for €38.-
(http://img188.imageshack.us/img188/836/p1010113medium.jpg)
(http://img188.imageshack.us/img188/4203/p1010114medium.jpg)
It is already fitted.
At the same time I revised the booster and made a new vacuum system.
(http://img208.imageshack.us/img208/3336/p1020461medium.jpg)
(http://a.imageshack.us/img62/6069/p1020589medium.jpg)
(http://a.imageshack.us/img827/8695/p1020636medium.jpg)
(http://a.imageshack.us/img44/3996/p1020641medium.jpg)
(http://a.imageshack.us/img90/7816/p1020642medium.jpg)
(http://a.imageshack.us/img62/4292/p1020607medium.jpg)
(http://a.imageshack.us/img251/6612/p1020606medium.jpg)
(http://a.imageshack.us/img821/4393/p1020643medium.jpg)
(http://a.imageshack.us/img834/7403/p1020648medium.jpg)
System from a Volvo.

I inspected the inside pretty carefully after honing it. I saw no pitting, so hopefully it will last. Like I wrote, the pedal is firm and stays in place when brakes are applied.

I am curious about your  vacuum booster. It looks like you have added an electric pump and a valve to prevent back-flow  ???

This is a vac-pump from a Volvo V40-60 diesel and it give a lot more vacuum then the engine.
(http://img37.imageshack.us/img37/379/p1020573medium.jpg)
This is the vacuum the engine delivers.
(http://img825.imageshack.us/img825/5361/p1020568medium.jpg)
(http://img46.imageshack.us/img46/9469/p1020565medium.jpg)

And this is the vacuum the Volvo pump delivers.
(http://img713.imageshack.us/img713/2348/p1020572medium.jpg)
At first I only mounted the pump.
Pointing at the brake was enough to block all wheels so I took a regulator from the same car.
It regulates a little weaker then the Murena standard, but you can adjust the spring in the regulator to what you need.
Also it cut off the pump when under pressure is build up.
(http://img641.imageshack.us/img641/7533/p1020574medium.jpg)
The regulator is  used to switch a relays, because motor ask 4 Amp, and it is to much for the regulator.
Every now and then the pump makes a few turns to keep under pressure on specs.
It works OK and no more vacuum lurking on the engine.
Of course the vac system needs to be in shape.
During the build a vacuum leak was found on the switch for the headlights wich was there for a longer time making the engine cripple on 1 cilinder.

I bet the headlights snapped up and nearly flipped over backwards ;D
closing them must have been a "snap" too. ;)

If you put skirts around the car, I bet you could suck it down to the road for some serious speed in turns. :D

Nice job though. I actually like the idea. :)

One of the reasons to do this was to get rid of the long vacuum route, and I didn't like the the way it was mounted on the inlet.
One cylinder had a lean burn as I noticed at the spark plugs.
I couldn't find the leak, but this system made me clear that the vac.switch was the problem.
Also I need the space to place a vaporizer for LPG.
Extra advantage is when towing the brake booster works and the the engine doesn't need running to get the lights up/down.

Is there a special trick for removing the brakemaster from the brakebooster, or is mine THAT rusted....? ???

No tricks, remove the 2 nuts and seperate.

Ergo rusted solid....
Seems like I have to secure it in a vice and give IT a few whacks with something heavy....

Problem fixed. A little tapping with a hammer on the studs made it give. But damn, it was rusted solid!

Oetker, there is an outlet on the brake master cylinder at the left bottom of it (refer to photo) for a wire in your car. What is it for? Originally it does not have.

Another question: Which cars use the same brake power controller as Murena? Are there any alternative part to install or a repair kit?

Normaly the master is from Bendix and the M10 connection is not there, however I found around 10 different manufacturers that made the Murena master cylinder.
Some have it and some don't.
Mine is from Lockheed an has the connection.
I presume it is for connecting a switch for the brake lights maybe used on the Talbot Horizon.
The Horizon use the same Brake master cylinder .
Also some Simca 1510 and 1307/8 and 1609/10

Concerning the brakebooster I did not have found a replacement yet.

Thanks.
I have a new master which is used in Horizon and it has the extra outlet. Some weeks ago I saw the photo of your car in a topic and I remembered that you have an extra wire from it. I just wanted to know what it is for. Probably I will close it with a blind cap. Maybe in the future if I would be bored... :)

I did not mean the brake booster. Sorry, maybe 'brake power controller' is not the right English name. I mean the item number 13056 in the illustrated parts catalog. Mine looks not so good...

Hi Klumzer

I think you will find that the red wire you can see travels up behind the master cylinder and that the extra outlet is blanked off. If my memory serves me well in the Alpine/Horizon cars the two front callipers had separate pipes running from the front of the master cylinder with a single pipe running to the rear brakes.

Regards
John

Ah you mean brake proportinal valve mounted right in the rear.
I never tried but this should be a solution.
http://www.ebay.co.uk/itm/Allstar-Performance-Brake-Proportioning-Valve-UMP-/300602932938?pt=Race_Car_Parts&hash=item45fd54beca

It is adjustable and you put it in the rear brakeline.
The original valve you can replace by a T-piece.
If you mount it in the car you can adjust brake balance in the car wich could be nice in bad weather.

Yes, I meant that one. I tried to translate the Hungarian expression... :D
First we try to save the old valve, but it is in bad shape. So if it fails now there are two other options. Thanks.

What is the second option? original??
Just to prevent mistakes.

Yes. Try to get a used valve in better condition.

Hello Herman,

have you some part ref and the scheme ?

Is it not more easy to use a Cruise Control 405 pump ?

(http://xrms.free.fr/phpwebgallery/galleries/bricolage/091219_regulateur_de_vitesse/thumbnail/t_002_pompe_a_vide_et_electrovanne_de_securite.jpg)

(http://xrms.free.fr/phpwebgallery/galleries/bricolage/091219_regulateur_de_vitesse/thumbnail/t_200_assemblage_pompe_a_vide.jpg)

Thank you

Mathieu

I think the cruise control pump will not be fast enough and will not reach the underpressure needed.
It is to small andprobably to slow.
This is what the Murena give from the engine.
(https://lh3.googleusercontent.com/-KGyNBrd7Oqs/T3YnV-y9gbI/AAAAAAAADuI/rdFAK6zEIZU/s800/P1020565.JPG)

The UP 28 Volvo pump is much stronger.
(https://lh4.googleusercontent.com/-94ojS42F8oQ/T3YnUhWzyBI/AAAAAAAADtw/UV8zQ167w3c/s800/P1020572.JPG)

I think the option of a Volvo up28 vacuum pump is very nice, but a expensive one too. I like to convert mij vacuum systeem too, but the pump cost about 145 euro's on ebay. Are there alternatives to get the same results, or does anyone know where to get this pump for less?

A cheaper way could be to make a trip to the next scrap-yard. You can find the UP 28 also at Volkswagen.

Hilsen

Kai

Diesel cars have a alternative pump to create vacuum.
Most of them have a mechanical one, but some have electric.
Look around a bit.
You will find a solution.

Hi everybody,

Herman, do you think that it's possible to post some schemes for a best explication ?

Greets Mathieu

When I find the time I will see in to it.
In the mean time this is interesting.
http://www.ebay.co.uk/itm/20-Hg-12V-VACUUM-PUMP-EV-Braking-Systems-Other-Vehicle-Uses-Wet-and-Dry-/261052931632?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item3cc7f79e30
There are more seellers that sell this pump.
My only doubt is dat it is not watertight and how much noise does it make.
It had good specs -20" Hg