MatraSport Forum

Each model => Murena => Topic started by: LarsB on April 10, 2007, 07:43:18 pm



Title: Removing trailing arms
Post by: LarsB on April 10, 2007, 07:43:18 pm
I am now regreting not taking my murena to a garage for changing the  trailing arm bushings.

The bolt going thru the inner bushing have rusted so badly i can not separete it from the inner metal tube of the bushing.
Any one have sugestions for removing this bolt?

the bolt going thru the outer bushing had to be sawed off, but for the inner bushing I really dont sea any way of sawing ( without removing the engine ::) :-\)


Title: Re: Removing trailing arms
Post by: Matra_Hans on April 11, 2007, 09:20:11 am
Hi
Unfortunately this is the normal condition (I think). I had to saw off the ends of the bolts in my own Murena, this was done with an electric Makita hacksaw, I do not remember the details, but it was difficult and time consuming.
Once you have the trailing arms out of the car the next difficult task is to get the rubberbushings out as the have a metal tube outside which is corroded to the trailing arms.

One advantage of doing the job yourself is that you can grease the bolts with cobber grease, which will make it easier to remove the arms next time (a workshop will newer do this).

Keep up the good work.

Hans



Title: Re: Removing trailing arms
Post by: Will Falconer on April 11, 2007, 10:35:21 am
If you cut the bolts between the bush and bracket, you can bend the bracket slightly to release the bush with remains of the bolt still inside.

Consider replacing bolts with stainless steel ones to make it easier next time. :)


Title: Re: Removing trailing arms
Post by: krede on April 11, 2007, 01:22:09 pm
I recall to have read that these bolts in fact were not even greased from the factory in the first place!


Title: Re: Removing trailing arms
Post by: Matra_Hans on April 12, 2007, 08:34:21 am
You are not allowed to use stainless steel bolts in this place. The MoT inspector will not approve the use, as stainless bolts do not have the same strength as ordinary steel.

Hans


Title: Re: Removing trailing arms
Post by: LarsB on April 12, 2007, 09:56:19 pm
Quote
You are not allowed to use stainless steel bolts in this place. The MoT inspector will not approve the use, as stainless bolts do not have the same strength as ordinary steel.


Then I wont tell him :-X

Did you cut the inner bolt of the right arm? Can not imagine how to get any saw to work in such tight space.

Lars Olav


Title: Re: Removing trailing arms
Post by: Lennart Sorth on April 12, 2007, 11:22:52 pm
You are not allowed to use stainless steel bolts in this place.
Really?!  - So many things on the Murena is designed to take loads much higher than the car will ever induce, so surely the dimension of bolts will be strong enough -  stainless or not ?

Modern cars however, have been "optimized" into being produced using the very minimal dimensions - driveshafts are like suction straws, and suspension bolts like safetypins. There I could see a problem.

/Lennart


Title: Re: Removing trailing arms
Post by: Will Falconer on April 13, 2007, 08:56:06 am
You are not allowed to use stainless steel bolts in this place.
Really?!  - So many things on the Murena is designed to take loads much higher than the car will ever induce, so surely the dimension of bolts will be strong enough -  stainless or not ?


I recommend the stainless bolts purely because they don't corrode and seize in the bush. Yes I'm sure the originals are more than strong enough for the job.


Title: Re: Removing trailing arms
Post by: Anders Dinsen on April 13, 2007, 11:41:53 am
.... and once it's all off and on again, give it a good rust protection - that will keep the stainless bolts hidden and prevent parts from rusting together.

Any progress on getting the arms off, Lars?


Title: Re: Removing trailing arms
Post by: Matra_Hans on April 15, 2007, 11:41:57 am
Hi
Lars wrote:
Did you cut the inner bolt of the right arm? Can not imagine how to get any saw to work in such tight space.

As I remember I cut both ends of all 4 bolts but the job was done a few years back so I do not remember the details. But you can disconnect some of the engine mounts and move the engine around quit a bit.

regards Hans

PS I am in the Sudan for the next year, so I will be driving Landcruisers instead of Matras.
To my big surprise the internet connection from here is acceptable!


Title: Re: Removing trailing arms
Post by: Lennart Sorth on April 15, 2007, 02:16:18 pm
PS I am in the Sudan for the next year, so I will be driving Landcruisers insted of Matras.
To my big surprise the internet connection from here is acceptable!

Cool, - you do get to travel quite a bit.

Sorry about the lack of Matra's, but you can enjoy the fact that your Internet service probably is better than what BT & friends actually *deliver* in the UK...

Have you installed a webcam overlooking your Matra-farm, so you can have a look when you miss it ?

/Lennart



Title: Re: Removing trailing arms
Post by: krede on April 15, 2007, 08:46:06 pm
I suspect he just went to have new sets of upholstery cheaply made for the rest of his matras!!  ;) 


Title: Re: Removing trailing arms
Post by: Matra_Hans on April 15, 2007, 09:42:45 pm
Hi
I have not yet checked the car cussion makers here in Khartoum, but I do need a roof lining for one or two Ranchos.
Hans



Title: Re: Removing trailing arms
Post by: krede on April 15, 2007, 10:47:59 pm
I rest my case... :D


Title: Re: Removing trailing arms
Post by: Lennart Sorth on April 16, 2007, 10:30:04 pm
but I do need a roof lining for one or two Ranchos.
hmm - be advised that Camel wool is terribly scratchy
But of course, in a Rancho you have whats called headroom, - something we haven't heard about in its sportier sisters :)

However, how about some Persian floor mats ... :)

/Lennart


Title: Re: Removing trailing arms
Post by: LarsB on April 21, 2007, 11:45:19 am
Fianly both trailing arms have been removed from the car. After several days spraying penetrating oil on the bolt it had to let go.

Unfortunatly the arms are not as rust free as I hoped. The shockabsorber bracket will have to be remade as well as some minor reinforcements on the arms. As soon as the weather premits I will get them sandblasted and primed.

Lars


Title: Re: Removing trailing arms
Post by: Lennart Sorth on April 21, 2007, 07:40:30 pm
Fianly both trailing arms have been removed from the car. After several days spraying penetrating oil on the bolt it had to let go.

Unfortunatly the arms are not as rust free as I hoped. The shockabsorber bracket will have to be remade as well as some minor reinforcements on the arms. As soon as the weather premits I will get them sandblasted and primed.

Lars

Congrats on getting them out. Good going!
It is however not really a surprise that they are worse than you thought. Hand on heart, I think most owners would say the same of theirs, if they had a look. :/

Be advised that of the outside is so corroded that you will have to remake the shock absorber bracket, then the *inside* will probably be much worse...

I wish one could dip the whole thing in some sulfuric acid, and then treat them in a way that would seal them from the elements. But as it is, they corrode, and will always do so :(

The alternative is to have new ones made up, reusing the hub. I think MatraMagic still offer this ?

Over the years, many have come up with designs for new arms in exotic materials like extruded aluminium or even simply galvanized steel - but as far as I know, nobody have yet done it for real ??

/Lennart


Title: Re: Removing trailing arms
Post by: Matra_Hans on April 22, 2007, 08:10:27 am
Hi
Renovation of trailing arms: I agree with Lennart that you should have a closer look at your trailing arms now they have been disconnected from the car. I changed mine a couple of years ago and I was really chocked when cut up the old ones and saw how bad they really were.
We have had some set of training arms for the 2.2 repaired at a machine shop here in Denmark reusing the original hub. We had plates for 10 sets laser cut, and I think that there are still some in store. The design was improved a little  i.e. the steel quality is better than original, and where the sides of the original arms had double layer of steel plate (very bad for rust) we used only a single plate but of a thicker dimension. On my own set I closed the original “drain holes” and put approximately 10 cc of rust preventing oil inside.
My new trailing arms are not stainless, but they are much better protected against rust than the original ones, and the original set of trailing arms lasted more the twenty years.
The price we paid for this trailing arms was very competitive.

Regards from the Sudan
Hans


Title: Re: Removing trailing arms
Post by: Will Falconer on April 22, 2007, 10:48:23 am

The alternative is to have new ones made up, reusing the hub. I think MatraMagic still offer this ?

Over the years, many have come up with designs for new arms in exotic materials like extruded aluminium or even simply galvanized steel - but as far as I know, nobody have yet done it for real ??

/Lennart

We looked at various options. I liked the idea of a stainless steel spaceframe most, but in the end the only viable soution was an improvement over the original using heavier grade steel.

 Galvanising of course creates it s own problems and we've shyed off doing that because of the distortion dangers.

If a Bagheera shell really can be cooked at 500C without any distortion I guess a Murena trailing arm should be OK too.  BUT, why didn't Matra do that? I think they knew what they were doing...


Title: Re: Removing trailing arms
Post by: Matra_Hans on April 22, 2007, 01:15:28 pm
btw. stainless trailing arms are available from Polytechnich (at least according to their web-page) but they come at a price: 605€ plus VAT each!
http://www.politecnic.com/brasarriere.htm

Hans


Title: Re: Removing trailing arms
Post by: Anders Dinsen on April 22, 2007, 02:26:44 pm
btw. stainless trailing arms are available from Polytechnich (at least according to their web-page) but they come at a price: 605€ plus VAT each!
http://www.politecnic.com/brasarriere.htm

They say they are strengthened ("renforcée") and made by CrMo steel - AFAIK that's not entirely stainless - strong, but not stainless.

- Anders


Title: Re: Removing trailing arms
Post by: LarsB on April 23, 2007, 07:47:06 pm
Hi
Renovation of trailing arms: I agree with Lennart that you should have a closer look at your trailing arms now they have been disconnected from the car. I changed mine a couple of years ago and I was really shocked when cut up the old ones and saw how bad they really were.
We have had some set of training arms for the 2.2 repaired at a machine shop here in Denmark reusing the original hub. We had plates for 10 sets laser cut, and I think that there are still some in store. The design was improved a little  i.e. the steel quality is better than original, and where the sides of the original arms had double layer of steel plate (very bad for rust) we used only a single plate but of a thicker dimension. On my own set I closed the original “drain holes” and put approximately 10 cc of rust preventing oil inside.
My new trailing arms are not stainless, but they are much better protected against rust than the original ones, and the original set of trailing arms lasted more the twenty years.
The price we paid for this trailing arms was very competitive.

Regards from the Sudan
Hans



How much ? And where do I inquire to have a set made? 

When you cut yours open did you notice that one of the arms were heavyer built than the other? One of mine seems to be doubled up.

Lars


Title: Re: Removing trailing arms
Post by: LarsB on May 07, 2007, 10:14:59 am
Do you have any more information about the lasercut arms, are there any more left, and what is the price for a set.

Lars Olav


Title: Re: Removing trailing arms
Post by: Matra_Hans on May 07, 2007, 07:46:48 pm
Sorry I did not notice your posting. However I am excused at I am now in a rather remote area of Sudan, and some days our internet connection is just hopeless.
From what I know of trailing arms being made there must be some sets left of the 10 sets, which we had cut.
As I remember it the price was 50 % of the price Simon is asking and the quality is better than the original ones, as they do not have two layer of two mm plats on top of each other no the sides but one thick plate and the materials is a stronger and rust resistant chrome alloy steel, maybe close the ones that Politecnic is offering. I do not have the e-mail to the guy in our Danish club who knows the machine shop, but I will off line e-mail you his phone number. Our chairman in the Danish club “Bagheera Lars” will also be able to help you.
You are asking if the arms on the left and one the right have different material thickness, and the answer is: No. But many trailing arms have been repaired by welding on additional plate on top of the existing rusty ones, and if you do a good job the guys at the inspection will not notice. So maybe you are having on original and one repaired one.
regards Hans