Too cold S3??

[Phil C]

Contrary to the normal 'how to cure an overheating problem' I seem to have the opposite. One that won't warm up....
Suspected the thermostat, so spent a few merry hours over the weekend replacing that - drove it on Monday and all seemed well - temp gauge steady at 90 and now the new 'stat seems to be working correctly.

However, this morning on way into work the temperature sat stubbornly at between 60 - 80 deg (as far as you can tell from the gauge) and only got up to 90 after 3-4 mins stopped traffic. I had a new (s/hand)gauge and sender fitted a short time ago - it's had the problem since - but I'm ashamed to say I haven't driven it that much.....

Any ideas? I'm beginning to suspect the replaced gauge....

BTW: the heater seems to be putting out a reasonable amount of heat (for a TVR!!).

[thegamekeeper]

Try checking the water temperature with a thermometer. That will tell you what the actual temp is. Often the gauge and the sender are not compatible so it could be either

[S3DaveP]

My S3 does that normally, if you drive from cold and never stop in traffic you can do 20-30miles and the temp is about 75ish. If you stop in traffic for 5 mins it reaches 90 and stays there even if you stop for a couple of hours it goes back to 90.
I have given up worring about it!! just one of those strange but true things.

Cheers

Dave Pelling

[dangerous]

Sounds just like mine,on my 12 mile drive to work each morning it never gets above 70 degrees and only ever gets to 90 if its sitting in traffic not moving (no air flowing over the engine),tried blocking off the grill between the 2 front spots and that made the temp go up to just below 90,personally I dont worry about it.

[spivvy]

S3DaveP said: My S3 does that normally, if you drive from cold and never stop in traffic you can do 20-30miles and the temp is about 75ish. If you stop in traffic for 5 mins it reaches 90 and stays there even if you stop for a couple of hours it goes back to 90.
I have given up worring about it!! just one of those strange but true things.

Cheers

Dave Pelling

mine does the same too must be a design feature

[Podie]

Snap.

[RichardR]

During the winter mine would only get up to 90° with the aid of a traffic queue. Made those long motorway journeys a bit chilly - too much air and not enough heat!

[trevytrev]

Mines the same !!!..

I changed the thermostat because it never got very warm and the gauge only just moved of cold ...

After changing the thermostat it would get up to 90 and stay there but as I topped up the water the next couple of times I used it, it dropped down to around 70 and now only seems to go up if I'm sat in traffic..

[Phil C]

All,

Thanks for the great response. And I thought I was the only one with a chilly Tiv!!! Bizarrely though the heater actually chucks out a reasonable amount of warm air - with the fan on...

Liked the incredibly logical and simple suggestion to test the coolant temp with a thermometer - now why the heck didn't I think of that??.... Thanks Steve.

My only problem remains, dare I boot it on the way into work (15 miles of free flowing country lanes) if it never warms up properly.....

Last thing - went out lunchtime with a colleague from work - he took a quick look under-bonnet and reckoned the sender lead was loose....so some more twiddling for the weekend...

Thanks again for the feedback.

[S3DaveP]

I only give mine some stick when the oil pressure has dropped ,its the only way to be sure the motor is truly hot. Oil pressure on mine is 60psi tickover 75psi running (COLD) and 35/40psi tickover 65psi running (HOT), i use this as a guide and this can take up to 20 miles to drop the these levels i only use 3000rpm till its hot.
I hope this helps, this is how i gauge the true engine temp, its only my opinion though!

Cheers

Dave P

[Fefeu52]

I know... the topic is not new But you can't tell I don't use the search engine.

I observed that my engine (S3C) needs a very long time to get warm (90°C). In fact I often need 30km to reach the correct temperature. I thought my thermostat was guilty. I don't have any overheat problem, even in very intensive use climbing mountains.

As I drained the coolant to refurbish the swirl pot, I got a new thermostat to replace it. But reading this topic, I'm not sure it is useful. It seems not to be so easy to replace because of the left side exhaust manifold going in front of the housing. Is it an easy operation ?

Thanks.

[LLantrisant]

the access is one problem...but the thermostat housing on ford´s cologne engine is a bit fragile with its 3-bolt fixing.....bolts tend to snap of, caused by corrosion and their tendenzy to seize.

[phillpot]

Access doesn't look a problem on my S3 but a Catylyst exhaust may be a different case?

Before you go tearing a perfectly good thermostat out (and as said bolts can snap housing can crumble) have a read of this old thread ...


And a bit more discussion here ............. cooling systen flow

[RayTVR]

LLantrisant said:

....bolts tend to snap of, caused by corrosion and their tendenzy to seize.

Yep, been there, done that

[Steve_D]

I've not read the other links so this may be covered there.

Start the car from cold with the bonnet open allowing the car to warm up.
Hold the top hose. If it gradually warms to a point you can't hold it any longer then the stat is jammed open.
What you are looking for is the hose to start gradually warming (by heat transfer past the stat) then to quite quickly heat up as the stat opens.

Steve

[GreenV8S]

Don't some of these models have a design flaw where the degas flow goes through the rad? I seem to remember somebody pointing that out in the past.

Edited by GreenV8S on Tuesday 27th November 16:44

[Fefeu52]

Thanks for the reply. OK, with the diagram it's more clear. In fact the cooling system is design to warm up gradually, very slowly, certainly to protect head gaskets from thermal chocks. Actually, my car seems to work normally, so I will not look for problems by trying to change the thermostat.

[GreenV8S]

Fefeu52 said:

In fact the cooling system is design to warm up gradually, very slowly, certainly to protect head gaskets from thermal chocks.

I highly doubt that was a design goal. Usually, a rapid warm up is a requirement. But in the case of TVR cooling systems, if it doesn't leak and doesn't overheat in typical conditions, I'd take that as a win.

Edited by GreenV8S on Tuesday 27th November 16:44

[Fefeu52]

GreenV8S said:

I highly doubt that was a design goal. Usually, a rapid warm up is a requirement.

I can't imagine an engineer designing such a complicated cooling system by accident. Rapid warm up is needed to limit pollutant gas, but increases strains in the engine, especially in the head gasket. But if you didn't give a dawn to the pollution....and that was the case in 80's ; If you have head gasket failure problems on your engine..... and that was the case on the first 2,8l Capri engine ; If you are designing a sport car that will be treated roughly and not a small citizen car.... designing a cooling system that will be a little long to warm up but with more stability and more homogeneity in the engine temperatures is not so surprising.

GreenV8S said:

But in the case of TVR cooling systems, if it doesn't leak and doesn't overheat in typical conditions, I'd take that as a win.

I agree with that.

[GreenV8S]

Fefeu52 said:

I can't imagine an engineer designing such a complicated cooling system by accident.

This is a TVR cooling system you're talking about. Not so much designed as built, and then any unconnected hoses blocked off.