Radiator

The size, design and position of the GTA rad is truly awful !
It looks too small, has inlet & outlet positions in stupid places and a fan mounted on one side

I'm tapping off the temperature switch and bringing an override switch onto the dash, so I can have the comfort of cooling the car down at will.

Andrew, I did as you suggested and bled the rad via the flexible pipe. Didnt appear to be too much air (if any) in there, but I'll take it for a run over the weekend and see how the temp performs.

Rgds
Paul

Fitting an override switch is a waste of time .
Over 30 mph and the fan isn't doing anything .If it's all working as it should the temp switch on the rad is all you need .
Better to spend your time making sure the system is flushed correctly and in top notch order .
If it's overheating regularly then you have a problem that a switch won't solve .

Depends what we term overheating.
Mine creeps up to 70 and stays around this level. But, if i'm stuck in traffic, not moving, then I have to wait till it reaches 110 or more before the rad fan kicks in. I'd rather use a switch to turn on the fan before I get anywhere near to 110 .

Rad switch fecked and/or an airlock ......It should switch at just over the 90 on the std gauge .....
As I said ,fitting an override is just masking the underlying issue .......

In that case it's either bad connections or a dodgy temp switch on the rad.
Are the temp switches standard item from Renault or a special ?

Std item 77 number I think but my local factors stock intermotor ones for about £30
You need the two wire type

Worth checking Simon Auto. I got a new switch from him for around €15 - a couple of years ago, mind!

Interestingly, though, it switches at what the standard temp gauge reads as a bit over the 90. A bit higher than I was expecting, to be honest and not really any lower than the switch I took out.
In fact, I thought it wasn't working at all when I fitted it - but it was just that the fan was stuck and the motor blown.

You might find this interesting......I did this check on my Alp for another member yesterday which I promised to do for him, the results are copied below. I consider my Alps cooling system to be correctly working so I would be interested in comments regarding this test.
One other point to remember that the stats "starts opening temp" is 88`, and it is only fully open at 94`

" just done the test....normal running temp 88 to 90` indicated on the Alps own gauge.....after a brisk run, the fan cut in at around 96 to 98` having stopped and waited for it to come on.. Remember that the coolant is under pressure as with all cars these days, which if you remember your Physics at school, when a liquid is under pressure its boiling point is higher than normal. I dont know what it actually is in a car, but I suspect it is somewhere around 115 to 120`, so temps around 100` could be quite accepable".

Mine creeps up to 70 and stays around this level. But, if i'm stuck in traffic, not moving, then I have to wait till it reaches 110 or more before the rad fan kicks in.

Paul, what gauge are you using, my gauges center line reads 90`, and the end of the red sector reads 130`. Is the turbos temp gauge different to the Atmo`s?

I've disconnected the switch and sprayed contact cleaner in the connection.
Took it for a run and below is a photo of the temperature gauge with the fan coming on and off. i.e. it turns on for , say ten seconds then switches off, stays off for around 20 seconds then comes back on for ten seconds and so on.




[img][img]http://i297.photobucket.com/albums/mm226/pgoldsmith_photo/Temperaturemage224.jpg[/img][/img]

Is this normal ?

Today was a cooler day than the other day and which saw the temp gauge reach a lot closer to the 130 mark before the rad fan kicked in.

Sorry John, I should have read your post more fully.
Yes the gauge is the same as the one your Atmo GTA.
Another interesting point I note is, after you turn the engine off and then turn the ignition key to 2nd position (i.e. the position before you crank then engine), then the temp gauge reads a lower reading than before!

Is this normal ?

I would say it is.....where your needle is positioned is the same spot that my fan cuts in at which, if you read the above, I would say that is around 96 to 98`.
I have a diag of how I manually switch my fan on using one of the redundant switches on the dash, and a relay, if you want to go ahead with the mod, I`ll copy it to you if you wish

Another interesting point I note is, after you turn the engine off and then turn the ignition key to 2nd position (i.e. the position before you crank then engine), then the temp gauge reads a lower reading than before!

Wouldnt worry about that...these gauges do not work on the voltmeter principle, they work on a sort of bimetalic strip, being bimetalic they are operated by heat and will cool very quickly when current is removed, therefore when you switch on again they are cooler and will read lower, if you leave them on for a fairly long time they will creep up again, but very slowly

Ambient temp is irrelevant ,unless you are at twelve fathoms .....
The gauge seems correct for the fan cut in ...ask Jon for details of his headgasket bypass as well if you put in an override

My fan cuts in at similar readings on the temp gauge and like yours, sometimes seems to be reading hotter than other times before it does.
It's a long way from where the temp gauge reading is taken to where the fan switch is, which could explain why it's not the same every time.

I guess on most cars, where the radiator is right there next to the engine, the differential between the temperature in the radiator and the temperature at around the water pump (or where ever the gauge reads from) is a lot less.

I have to say that once I'd fitted the new switch (the work of but a moment, BTW) I was expecting it to behave much more like modern cars where the temperature needle doesn't leave dead centre. However, it moves about a fair bit - but doesn't drop below 88 or so once up to temperature - even with the new switch. In the end, I concluded that as long as the fan comes on in the black zone to the right of the 90 and BEFORE the orange bit, then that's OK.