| Home  Blogs Help Search Login Register  
« previous next »
Pages: [1] Print
Author Topic: Murena (or Bagheera) rear brakes  (Read 3379 times)
roy4matra
YaBB God
*****
Posts: 1199



« on: August 08, 2020, 05:41:29 pm »

I wrote a booklet, many years ago now, on the Bendix rear brakes as fitted to the Bagheera, Murena, and Espace I Quadra, explaining why they always seized, and how to strip them and rectify the problem, because everyone either had had this problem or would get it, as it was inevitable owing to the design and materials used.  When I first wrote it, the normal rear brakes fitted to most cars in the U.K. and Europe, were drum brakes, and since these were discs with self adjusting pistons, and a combined hand brake mechanism, they were at the time unconventional, and many mechanics had no experience or knowledge of how to work on them.

Some of the Fiats in the sixties had a similar set up, but certainly in the U.K. back in the sixties the cars on the road here were mostly English and there were very few imports.

I bought my Murena new in January 1983 and after about 50,000 kms or 4 years, I had the problem of my rear brakes sticking badly, and stripped them to find out why.  I found out, rectified them properly and didn't have any more problems.  However, I then found I was not alone and others were having the same problems except that many if not all of other repairs were simply insufficient as they were not properly overhauled, so they would continue to have problems.  Some cars even ended up being taken off the road as they couldn't get them fixed other than by fitting completely new rear brakes, but that simply meant that in another few years the problem would happen again.

Hence the reason I wrote my Brake Manual.  This has been available from my website for many years as a free download, and as I have stated in it, if the brakes are overhauled exactly as I have outlined, then you should have no further sticking problems.  Unfortunately many do not separate the alloy caliper from the steel mounting frame and clean away the corrosion, and if this is not done, the results will be poor and any improvement will last only a short time.

From my own experiences with the calipers I have overhauled, I know that they will last and have claimed this in that manual, that you can expect 10 years without further problems.  Recently Anders sent me the rear calipers off his Murena to overhaul, not because he was experiencing sticking rear brakes, but simply because he is doing a major restoration of his Murena which is coming up to 40 years old and decided it would be good if the brakes were checked as well.  This is a car I have known for many years, originally as I used to service it regularly for a previous owner in London, then I had it for approx. four years before selling it to Anders.  So I know when I did the first overhaul on the rear brakes, when Pierre owned it before me, and this is the first time they have been stripped since then.

I am pleased to report that they have lasted so well that they have been the easiest to strip in all the years I have been doing these and there was almost no corrosion which is why they were still free and working well!  So I have now increased my claim in the Brake Manual to say: a further '25 years' not Ten.  I know these particular calipers have not needed this work in fact in 30 years, but to be conservative I am 'only' claiming a further trouble free 25 years since different owners and cars are used in different ways and environments.

The outcome though is that if the calipers are overhauled correctly as I state in the manual, these are the results you can confidently expect.

Roy
« Last Edit: August 08, 2020, 05:48:32 pm by roy4matra » Logged

suffolkpete
YaBB God
*****
Posts: 544



« Reply #1 on: August 09, 2020, 01:27:11 pm »

Amen to that
Logged
Matraman
Full Member
***
Posts: 74


« Reply #2 on: August 10, 2020, 03:31:39 pm »

Glad to hear that Roy, I don't fancy doing that job again! I followed your brake manual and was able to get everything apart and know that I was applying force to the right areas without damaging anything. All the brake calipers are working perfectly now, after a few weeks back on the road. Thanks for doing these manuals.
Logged

Andrew
roy4matra
YaBB God
*****
Posts: 1199



« Reply #3 on: August 12, 2020, 06:22:21 pm »

Glad to hear that Roy, I don't fancy doing that job again! I followed your brake manual and was able to get everything apart and know that I was applying force to the right areas without damaging anything. All the brake calipers are working perfectly now, after a few weeks back on the road. Thanks for doing these manuals.

One of the most important parts of the overhaul is at the end when you fit the spring and locking button in the caliper hole - grease that well.  Then when you slide the alloy housing back into the steel frame, you not only want to use a good smear of grease to ease them together, because they should be a nice firm fit; but you then want to seal that joint so that water cannot get in.  I am now using ceramic brake grease, which Herman recommended, and it's really good.  Without water there can be no corrosion between the alloy and steel.  I normally make sure there is a smear of grease all along the join top and bottom and both sides.  Then also make sure there is greased packed down the frame hole where the locking button pops into to lock the two items together.  When I came to depress the button to separate the two parts on the calipers from Anders, those holes were still full of grease, so the buttons had not become corrodes and stuck.

The ceramic brake grease has a high melting point which is what you want where brakes are concerned.

Roy
« Last Edit: July 27, 2021, 09:01:34 am by roy4matra » Logged

Oetker
YaBB God
*****
Posts: 1097



« Reply #4 on: August 25, 2020, 01:57:05 am »

Hi Roy.
Good evoluation of the job after many years.
On my 2,2I have the the job done according  your bible 1n 2007 and my 1,6 in 2012,
a Few years ago a new grease appears on the market.
It"s called ceramic grease.
Its silicone based an can handle 3000F temps and seals good.
Most garages use it now and dumped the copper grease (wich I never trusted because of bringing in a 3rd metal good for extra corosion.)
I have it now in the house and wil use at the next brake job.
Logged

I feel like Jonah, only my fish looks different.
Murena 2.2 Red 1982. Murena 1.6 black on places.
roy4matra
YaBB God
*****
Posts: 1199



« Reply #5 on: August 25, 2020, 05:39:48 pm »

Hi Roy.
Good evoluation of the job after many years.
On my 2,2I have the the job done according  your bible 1n 2007 and my 1,6 in 2012,
a Few years ago a new grease appears on the market.
It"s called ceramic grease.
Its silicone based an can handle 3000F temps and seals good.
Most garages use it now and dumped the copper grease (wich I never trusted because of bringing in a 3rd metal good for extra corosion.)
I have it now in the house and wil use at the next brake job.


That's good to know about, thanks Herman.  I will look out for it.

Roy
Logged

Pages: [1] Print 
« previous next »
Jump to: