MatraSport Forum

Hello all,  I have a set of 36dcnfs off a Bagheera to fit to my 1.6 Murena. The manifold needs a connection for the top hose from the expansion tank. What is the best place to tap into the manifold for this? Or do I tap into the end of the thermostat housing?
Looking at the internet I have come up with the below picture with the pink air filter showing the connection on top just right of the thermostat housing. (first picture)

Next two pictures show my original set up. The hose that comes off the expansion tank with the brass reducer. Do I need to reduce the hose or can I just fit a straight hose from the expansion tank to the manifold?

The last picture is of the parts I have to fit with no connection for the hose.

Cam will need work, I know. Thanks in advance.

I don't think I'd tap into the thermostat housing, they are very brittle.  It's a de-gassing connection, I think, so needs to come off the highest point, though if the Bagheera can manage without it, perhaps you can.  Try just blanking off the header tank connection before you start drilling holes in things.

Thanks Peter,

But it must be there for a reason. I think the Baggy has a vent but elsewhere so I should do it. I'm going to fit the carbs without cam profiling at first. The spare engine will be done over the next few months with that lightened flywheel properly balanced with the crank. I'm still getting an all envasing din at 3000rpm which I'm now thinking is down to this.

By the way... I now have a Rancho. OH NO!!!!

And... is it necessary to reduce the hose as the original or can it be a straight section of hose?

Hi Titus

I know this hose well on the 2.2, where it's also connected on the thermostat housing. It's there to bleed air out from the thermostat housing into the expansaion tank. I'm not sure how your new manifold is constructed, but it sounds like a good idea to copy the setup from the guy with the pink filter. I would keep the hose thin (I think it's a 6 mm originally until it's stepped up, right?) because it was so originally - I don't think it would matter going up in size and making it a straight section, but I'm not sure either. Besides, you have the correct reducer already.

/Anders

On further thought, I'm inclined to agree with Anders.  I believe the connection is there to aid filling the system when the thermostat is shut, so the setup in the top photo looks like the correct way to do it.
Better learn to weld then  ;)

Indeed, it is to get the air out of thermostat housing.
But there are 2 types of that housing.
One with a bolt, and one with a connection.
On the parts manual you can see the 2 possebillitys wich are not in the WS manual.
(http://img571.imageshack.us/img571/8280/koel2.jpg)
Also there are 2 types of thermostats.
One with internal degassing, and I presume degassing is not needed when this one is mounted.
(http://img263.imageshack.us/img263/7684/thermost1medium.jpg)
(http://img254.imageshack.us/img254/8951/thermost2medium.jpg)

If this is of help, waterhose routing.
(http://img255.imageshack.us/img255/8484/koelslangen.jpg)
 

I would say keep the bleed pipe but restrict it to around 3mm, if the the connection is too large too much hot water will bypass the cooling system.

Regards
John

There is a standard limiter for it.
Also remade by Simon in metal

Thanks very much for all the advice. Will let you know how it goes.

I now have a brass hose end to tap into the top of the Bagheera manifold. 1st picture. The diameter of the hole is 4mm. This is the smallest I could find.

On the original hose connection to the manifold this connection only has a hole diameter of 1.5mm ish. Second picture below the thermostat housing.

As there is a brass reducer in the hose between the manifold and expansion tank. Picture 3. Does it matter that my new brass hose end into the manifold has a larger outlet hole? ie 4mm vs 1.5mm. Or does this reducer do the job regardless of the connection to the manifold?

I could of course take the original hose end out of the original manifold and use this but I don't wan't to risk breaking things and I may need to revert to my original single carb set up. So I want to leave this alone.

Any thoughts please. Thank you.

There will be no more flow then the smallest hole in the system.
If the reducer has the same size on the smallest point you will be OK with it.

Thanks Oetker,

Well, I've made a start. Notice the top brass hose connection now tapped into the manifold as previously asked here. Thanks for the advice chaps.

The pictures look like I have hoses connected but they are not. Some will need modification. I'm wondering how to replace the 1.6 Murena vent from the rocker cover  via the green 'frog' to the original filter pan. I'm now using Bagheera Series 1 manifold on top of the twin 36DCNFs with no connection for this. How does the Baggy vent from the rocker cover?

All being good I'll be up and running for the MEC UK rolling road session at the beginning of April. Then all will come out again for the new engine transplant including the fast road cam and a much needed clean and paint of the engine bay.