MatraSport Forum

The gauge indicates the engine is running at around 60 celsius.  I'm guessing it should be more like 90.  

My cabin heating is pretty weak.  The "hot" air setting is pretty lukewarm so I'm guessing the engine really is running cold and probably needs a thermostat OR the heat matrix is clogged up after 25 years and the gauge is inaccurate.

I'm hoping it's the first one.

Thanks
Roly

First of all, the Murena heating system was never really able to
give you any (hot) air worth talking about.

I would check the temperature by some other (better calibrated)
means, before upping the thermostat, - but of course replacing it
with a standard-spec should be ok.

PS: Yes, I'm a whimp, - I've had too much experience with very hot engines - so I'm almost always looking at the temp-gauge when I'm  driving  :-)

Well I'll start with the thermostat - looks pretty straightforward to change it (for a standard spec).  

I've never heard a radiator fan kicking in - is there one?

Cheers,
Roly

Yes there is a rad switch and it's surprisingly easy to change - although many people have fitted over-ride switches because they mistakenly don't trust the rad switch

In my experience 1.6's run very cool and your temp gauge sounds about right.  :-\

The voltmeter in fact has a geniously designed feature ... (well caused by poor contact from the battery/fuseboard to the dashboard, but nevertheless :-) )

When the car runs, you will probably have a reading just outside the left filled rectangle. But if you turn on the wipers, it will drop. NOT because the battery-voltage drops, but because of the small resistance on the way TO the dashboard.

Similarly, the meter will drop a little, when the radiator fan kicks in. That is VERY convenient. Almost as good a "safeguard" as the override switch some install.


/Lennart

I'm sorry Will but that is wrong.  No engine should be running with a temperature around 60 degrees.  If the engine is running correctly at around 88 degrees, then when you are stood in traffic you will need the radiator fan to cut in and keep the engine from overheating.  Radiator switches are not very reliable and never have been, and I'm talking from many years of experience and on all sorts of cars not just Matra.  Why do you think Ford used to fit a by-pass in the wiring loom on many models? (it was so that when the switch failed all you had to do was connect the plug and socket and the fan ran all the time).  It was also one reason why the manufacturers got rid of them?  Radiator fans are now controlled by the injection computers and block coolant sensors.

Consequently an over-ride switch is a very sensible addition.  Without one you have no option but to stop the engine to let it cool, which is not really practical.  Or worse the engine overheats and you damage the engine.  Not very clever.

So in answer to Roly's question, I suspect his thermostat was stuck open if indeed there was one fitted.  Please replace it but after you do, please make sure the radiator fan switch works, because after many years without it working you might find it has failed.  On many cars I have worked on, one service item is to let the engine warm to the point where the radiator fan cuts in, to check the system is working correctly.

If the engine coolant is running at the correct temperature the interior heating will be fine, assuming everything else is O.K.  The Murena, both 1.6 and 2.2 in my experience, were fitted from the factory with 81 degree thermostats which was probably O.K. in the south of France, but here you really need and 88 degree one.  Unless we ever get any of this global warming that they keep promising... :-)

Roy

I respectfully disagree!! :) ... mine works just fine!... EVEN without the the fans switch on fire  :D

 

+1

To fit an override switch costs a few pounds and takes seconds to fit, to sort a cooked engine, well too much money and too big a risk for me!

I dont think the 1.6 is anywhere near as prone to cooking as the 2.2 is it?
I have always believed that it was the early cast aluminium cylinderheads that was the big issue in this regard?

I've cooked one - on the M25 years ago. Lost the frost safety plug at the bottom of the radiator, then drained all coolant on the M25, and that was it.

Since then, I developed a third eye, always focusing on the temp gauge :)

/Lennart

And my fourth eye is checking the rearviewmirror to spot a cloud when a cooling hose separates from the pipe. Happened two times.

After loosing the coolant fluid due to the radiator disintegrating and because I only have two eyes I have develop at water level sensor that gives visible and audible alarm.

Hans

Hans.. you showed me your work.. and I have decided to steal the idea :),
I have roamed a couple of scrap yards for suitable "donors"...(didn't you use a BMW sensor?)

I would prefer to use the Murena expansion tank, but Im not sure a sensor can be "glued/welded" into the plastic without it leaking.
Alternatively I have thought about swapping the tank entirely... various can be used... but the most promising are from mid 80's vw passats, and v6 ford Scorpios... but some of the plumbing is different.

can someone tell me where to buy thermostat for 1.6l engine in sweden?  Id like the 88degres :)

im with roy on this one.there are many aftermarket devices available to enable the fan to cut in.at the moment my fan runs constantly.that way i know its gonna cool the engine ok,and the car wont overheat-----hopefully.
steve