Serious challenges.

[Jon Weywadt]

The other day it finally became time to pull the head off the engine. It needed a valve job and It had been blowing white smoke/steam from the exhaust when starting in cold weather.
My hope that it was just a leaking valve seal and bad head gasket was dashed when it turned out that the head is cracked right at the exhaust valves in the middle cylinders.  
Getting the head off while the engine is in the car is a pain in the ass.  But I succeeded. It is now at RMC Motors where they will grind the cracked part away and weld up a new wall, grind new valve seals, have the valves done, and the bottom planed.

But a couple of questions.
First. Because of the cracks in the head, a little water had gotten into the oil and while not much, how do I best clean it out of the engine?  

Second. While dismantling an important step is to loosen the timing chain by removing the plug covering the screw that pulls it back, then turning the screw clockwise to pull the tensioner back. Jan and I tried everything to get the screw to pull the tensioner back, but to no avail. It turns out the the tensioner is very loose as if there is no spring behind it. Also the screw that is supposed to pull it back did not seem to engage and did not move the tensioner at all.
So what could be wrong? My guess is that it is defect, but there was no indication of that when the engine was running. Granted it ran very rough, only firing on 3 cylinders and no vacuum with several hoses cracked.

The oil plan comes off so we can inspect the tensioner and I think the proper thing to do is to just replace it. Anyone with experience here?

Once the engine is running the next big job is to pull the gear box and take it apart. The second gear synchro cone is too small for the synchro ring. Already replaced the synchro ring once and it lasted only a few months before riding against the gear, again grinding when shifting into 2nd. gear.
The plan is to put the second gear wheel on a lathe and take off 1 mm where the synchro ring presses against it, thus allowing the ring to engage the cone more firmly. Alternatively, shave a bit off the side of the synchro ring that rests against the gear, thus also engaging the cone more firmly.

Probably should have pulled the engine out completely to make it easier to get to all the parts.

[Matra_Hans]

Cracks in the cylinder head are very difficult to repair: I have had a try myself. The company repair some cracks, but other cracks was left undone. And you get new cracks at the edge of the weldings.  I recently talked to a guy who worked in en engine repair workshop, and he commented that in his opinion repairs of cracked cylinder heads did not work.
It is a pain in the neck to loosen the hydraulic timing chain tensioner. However there are two types: One to be operated with a normal screws driver and another to be operated with an Allan key. Which one do you have?
Hans

[Oetker]

There should be 2 types of spanners but I only know this one.
https://www.youtube.com/watch?v=30FxWH0nl3A

The Cil.heads are  a pain.
Welding is possible but not in all cases.
2 heads of a fellow member.


Pics Fjodor
Maybe find a better one.

Herman

[roy4matra]

The other day it finally became time to pull the head off the engine. It needed a valve job and It had been blowing white smoke/steam from the exhaust when starting in cold weather.
My hope that it was just a leaking valve seal and bad head gasket was dashed when it turned out that the head is cracked right at the exhaust valves in the middle cylinders.  
Getting the head off while the engine is in the car is a pain in the ass.  But I succeeded. It is now at MC Motors where they will grind the cracked part away and weld up a new wall, grind new valve seals, have the valves done, and the bottom planed.

But a couple of questions.
First. Because of the cracks in the head, a little water had gotten into the oil and while not much, how do I best clean it out of the engine?  

Second. While dismantling an important step is to loosen the timing chain by removing the plug covering the screw that pulls it back, then turning the screw clockwise to pull the tensioner back. Jan and I tried everything to get the screw to pull the tensioner back, but to no avail. It turns out the the tensioner is very loose as if there is no spring behind it. Also the screw that is supposed to pull it back did not seem to engage and did not move the tensioner at all.
So what could be wrong? My guess is that it is defect, but there was no indication of that when the engine was running. Granted it ran very rough, only firing on 3 cylinders and no vacuum with several hoses cracked.

The oil plan comes off so we can inspect the tensioner and I think the proper thing to do is to just replace it. Anyone with experience here?

Once the engine is running the next big job is to pull the gear box and take it apart. The second gear synchro cone is too small for the synchro ring. Already replaced the synchro ring once and it lasted only a few months before riding against the gear, again grinding when shifting into 2nd. gear.
The plan is to put the second gear wheel on a lathe and take off 1 mm where the synchro ring presses against it, thus allowing the ring to engage the cone more firmly. Alternatively, shave a bit off the side of the synchro ring that rests against the gear, thus also engaging the cone more firmly.

Probably should have pulled the engine out completely to make it easier to get to all the parts.

Last thing first - yes drop the rest of the engine and transmission out, separate them, and then do the engine properly.  With the cylinder head work, you need to fit a new water pump, new thermostat, new seals and gaskets and you may as well fit a new vee-belt.  Also check the condition of the block core plugs.  This is the time to replace any that are suspect.  Remember the timing cover must be bolted to the cylinder head before the head face is skimmed (or re-surfaced) - it MUST be exactly the same level.  Also remember when you torque the head down, it must be AFTER the timing case is already on and torqued up. (which means the cam gear and chain must already be on and set)

Regarding the timing chain tensioner, whichever type, you must push the screw inwards before you try to turn it.  Did you do this?  If you tried to turn it before pushing and holding in, either it will not turn or you will break it.  Once you have turned it fully until it stops (about 3/4 turn IIRC) it will have compressed the spring and should lock the pad back in that position.  I doubt it was lose or faulty because it is such a long chain that if it had been, you would have heard the chain rattling! (and the running would have been poor even without the cracked head)  If you remove the sump with the engine still in the car, REMOVE the oil level sensor first otherwise you will probably damage it, and you cannot get them anymore.

With the engine out to strip fully, you can clean the inside of the engine and oil pump/strainer etc.  If the cracks are only between the water jacket and the exhaust valves, it is probably that no coolant will have got in the oil anyway.  When you drain the oil of an engine where you suspect there may be coolant in the oil, the coolant will always be at the bottom and first out.  Oil always lays on the surface of water - remember?  So when you release the drain plug always check if any coolant or water comes out first.

Regarding the gearbox, be careful about grinding the sides of gears to get the synchro to work.  The synchro mechanism has to lock in place once engaged and if you alter the amount it has to move it may not lock and then the gear may 'jump out' under acceleration.

Roy

[Jon Weywadt]

----
Regarding the timing chain tensioner, whichever type,
----

Regarding the gearbox, be careful about grinding the sides of gears to get the synchro to work.  The synchro mechanism has to lock in place once engaged and if you alter the mount it has to move it may not lock and then the gear may 'jump out' under acceleration.

Roy

Thanks for the info and warnings.
I did push the screw in as hard as I could, but it turned freely apparently not engaging anything. However, it was possible to get the sprocket wheel off the cam and free of the chain, so the chain could not have been under tension. However, afterwards I noticed that the whole tension mechanism was loose and could pivot. It does not seem right.
Just in case I got a new tensioner from Simon and it has a different release mechanism. It has a clasp in the side of the mechanism, which releases the spring when turned and push the tensioner forward.
I am curious how to do that once installed in the engine? I do not recall a hole on the side like the one on the front where once the plug is removed you can get to the screw. I included photos of the new tensioner.

With your warning about grinding the side of the gear or synchro ring I wonder what options I have. I already tried a new Synchro ring from Simon a few years ago and it lasted only 6 months. I need a ring that better fit the gear or a gear that fits the ring. But where can I get that?

[Oetker]

I have another box mounted since de revised  one had trouble with 3e gear.
It's from my breaker.


I bought it for the ashtray  


Litlle miles


I got the engine and gearbox out and seperated them.



Before that I got the gearoil out and this box looks like a chalenge.


This box is the later one so somewhere in its life it was changed.




Here the problems I noticed before in other boxes with 3e gear.
If you have this it's best to chamge the comleet 3/4 group.


Testing the differential I noticed this.
https://www.youtube.com/watch?v=3ryVMsTnmmA&feature=youtu.be

The problemis the satelite on the right side.
 I saw this before in another box.
Probably to much force wehen working on the right arm.



In this box I machined a bit of the synchro's 1-3-4.
I suggest to do no more then 0.5 mm and replace 2nd gear synchro and gear.



On 2nd I mounted a new one.


Tested the box.
https://www.youtube.com/watch?v=TWYvL4v-E0M&list=UUCVQxyhNeQGLzguASym0TBw

It's mounted for 5000km now and working perfect with no leaks.
The synchro's are easy to source because they are mounted in several boxes Fiat Citr. Peugeot and others.

The breaker is a transformer now.

The cat is happy with all the Matrastuff




Herman

[Jon Weywadt]

There should be 2 types of spanners but I only know this one.
https://www.youtube.com/watch?v=30FxWH0nl3A
-----
The Cil.heads are  a pain.
Welding is possible but not in all cases.
------

Herman

I got a new spanner as seen in my post above. It works with a screw on the side and I am wondering how it will be possible to release it, or later tightening it again.

I finally got the head back from repair. the shop cut away all aluminium to the bottom of the crack. Then welded new walls and installed new valve seats. I think it looks good. They claim it will hold as well as the original.

But just to be safe I am switching to the waterless coolant from Evans that I discussed in another post.

Finally I will take the radiator and have it re-corred before I run this engine again.

[Oetker]

If you want the old type spanner, I have a spare
Concerning 2nd gear, I have 3, but they are in a worse state not usable.
If you can find you can use Citroen CX 2nd gear from 1980 and later.
You need to find the right rings after that.
Simon has them.


Citroen gave the old shitty parts  to Matra first concerning this boxes.

herman

[Jon Weywadt]

Ok, so I started to take our spare gearbox apart, but I don't remember how to lock the gears so I can take the nuts off the 5th. gear shafts.
Who can tell me how, now that the box os on my wotkbench?

[Oetker]

Put the box in 2nd or 3th gear.
Loosen the bolt of the 5th slider.
Now you can engage 5th also.
The gears will be blocked and you can loosen the nuts.

[Oetker]

Pics




If you looking for pics and how to I loaded a lot up to this topic.
http://www.matramania.be/phpBB2/viewtopic.php?t=2305&start=0

Yest it's Dutch but pics don't need a language.
Herman

[Jon Weywadt]

Put the box in 2nd or 3th gear.
Loosen the bolt of the 5th slider.
Now you can engage 5th also.
The gears will be blocked and you can loosen the nuts.

I was actually thinking of that solution while waking up in bed this morning  So thanks, that confirms it.

[Jon Weywadt]

Pics

If you looking for pics and how to I loaded a lot up to this topic.
http://www.matramania.be/phpBB2/viewtopic.php?t=2305&start=0

Yest it's Dutch but pics don't need a language.
Herman

I did this back in 2010 and posted pics and a description. You would think I could still remember what I did, but I'm afraid not. 
Your picture with the pipe extending the wrench is exactly what I had to do back then. So now to clamp the box to the workbench so I can apply that amount of force.
My hope is that this spare gearbox has a good 2nd. gear. We shall see.

[Jon Weywadt]

There should be 2 types of spanners but I only know this one.
https://www.youtube.com/watch?v=30FxWH0nl3A
-------
Herman

Hi Herman.

Could you try something with your spare spanner.
With the spring removed and the piston re-inserted, could you see if the screw can be turned freely without engaging the piston?

When I tried mine the screw just turned. It could not be pressed in as it was already against the block.
The chain was loose enough that I could unscrew the sprocket wheel and get it out under the chain. Afterwards the spanner was just sitting in its block and loose to twist. It did not pop out, leading me to think that there was no spring installed.
If a previous owner has had it apart and not realised that the spring had popped out, it may be in the oil-pan.
Since the pan is aluminium I will take a strong magnet and sweep it from left to right along the bottom of the oil-pan. Hoping that if the spring is in there I can get it to roll over under the timing gears. I am able to get a telescope magnet down to the bottom but have not caught the spring yet. We shall see.

[Oetker]

Normaly I place the box on the ground against the wall.
I sit downon the ground  and press the box with my 2 feets against the wall
Then I take my torque wrench an apply strong force.
It will come loose if youre strong enough.
I look up the spanner (it's somewhere in the mess of parts) and will do so.
Bit patience, I have to find it first.

Regards, Herman