Clio mk1 - Clio mk1 overheating - advice please?

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Mon 25 Apr 2016 08:28
Clio mk1 - Clio mk1 overheating - advice please? - amyamandaallen

Hi,

I just bought a 1991 clio, 55k and all the stamping of book, almost a barn find TBH. Seems to drive fine.

Then....

The temp started climbing higher and higher until the red light came on. Heater in car was stone cold prior to this.

Opened bonnet and there wasn't any water at the bottom of the reservoir. Topped it up took about 2 litres. Took it for about a 10 mile trek and it sat at just under 2/3 unless you stopped and let it idle then the needle would start creeping up again. Heater would blow out warm/hot air whilst driving but at a few times colder ( not stone cold as before ) again. Fan never seems to cut in which might be the problem and I can hear hissing coming from the expansion tank cap.

Cant see any water dropping from underneath in last 24 hours
Under the oil cap looks black
Dipstick looks black
Had some white smoke yesterday at idle but that's gone at idle today ( it was sorn for 6 weeks when I bought it so suspect just condensation )
Water in expansion tank looks a bit murky red ( don't think that will be the HG gone )
Pressure when warm releasing expansion cap
Both sides of rad pipes get hot so think waters passing through.
Fuse for rad fan good

The missus doesn't want to drive it now so Im stuck til this is fixed.

Are the fans known for sticking? anything else to try or suggest please? any iffy switches ( though I suspect the switch must be working as temp gauge is climbing or are there 2 switches? )

Really grateful for any assistance please.

AMY

*update

Have left car overnight and no leaks.

Have looked deep into oil cover and def only black oil ( dipstick too ) no mayo on the underside of expansion cap ( so hopefully not HGF ). Expansion water looks just a bit murky red/brown. No White smoke from exhaust.

Wife drove it to work this morning and its was just below 3/4 mark on temp gauge unless she was at lights then it would start to creep up again fairly quickly. Heater 'warm'.

So thinking its the fan or fan sensor maybe? Will send power directly to fan tonight from battery to test it works ( assume that's ok? ) Fuse it good in box not blown.

Any help welcome please :-)

Edited by amyamandaallen on 25/04/2016 at 08:30

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Mon 25 Apr 2016 09:14
Clio mk1 - Clio mk1 overheating - advice please? - elekie&a/c doctor

Cooling fans were often a problem on these.Join the 2 wires together on the fan switch to see if it operates.Have you checked the correct fuse.Iirc ,the fuse for the fan is under the plastic cover ,in front of the windscreen.Also I would advise flushing the cooling system and filling with fresh a/freeze.

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Mon 25 Apr 2016 09:48
Clio mk1 - Clio mk1 overheating - advice please? - Fernando P

If the coolant has been filled up because it was too low, there could be air leaks to remove via the bleed valves at the top LHS of the radiator and the top of the nearside? heater flow hose. When the engine is up to temperature you slacken off the valves to allow the air to be expelled and keep topping up with coolant. If you are unable to do this, you need some practical mechanical help from somone who understands what to do.

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Mon 25 Apr 2016 11:25
Clio mk1 - Clio mk1 overheating - advice please? - amyamandaallen

Thanks. i will try the fan first as if that worked I suspect thats the issue. Will also do a bleed whilst there.

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Mon 25 Apr 2016 14:13
Clio mk1 - Clio mk1 overheating - advice please? - Railroad.

Even if the fan doesn't work, making it work will solve nothing if the radiator is cold when the engine is hot. Cooling systems on Renaults of this age are the easiest ever to bleed. Open the bleed screws and fill the system until all the air is out. The higher you hold the expansion bottle as you fill it the easier it will be. Don't run the engine with the bleed screws open as this will not achieve anything. It may pay you to change the thermostat too, as if it's stuck closed the engine will overheat.

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Mon 25 Apr 2016 22:25
Clio mk1 - Clio mk1 overheating - advice please? - amyamandaallen

Hi,

Quick update

Theres def no white smoke when idling now, so I do suspect that was from when it was sorn.No pressure when releasing expansion cap when cold. I taek these both as a good sign?

I bleed the rad, only one screw on the top of rad. Blimey this car is unmolested. Turn exactly as it should, very smooth. Liquid came out pretty much straight away. Powered fan and bridge fan sensor all good. Fan ran no trouble.

Wife used today for 2x6 mile trips, dont think it lost any but only new roughly where level was.

Let it heat right up and it sits just under 3/4 up the gauge when fully warm pretty much. Took it for a run, the needle moved a few points either way ( each section has 5 smaller points ) then pulled up for 7/8 mins and eventually after it was between 3/4 and the start of the danger area I heard the fan cut in and the temp gauge drop a few points. Tried this several times and all seemed good. Drove home.

Theres a definate heat difference between hot and cold settings. When you first turn heater up it blasts out then goes warmish but def not stone cold.

Got home and watch it do the up/down cycle again and opened bonnet when I thought I heard the fan. Saw that water is gushing back and forward in the expansion bottle and coolants leaking out through the cap!!!!

Can I assume that the gushing would be normal as it was towards the max filling when cold? Even through the cap I wouldnt have expected it to lose the 2 litres I had to top up by yesterday? Should the replacement cap fix the probs?

Cheers.

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Tue 26 Apr 2016 07:29
Clio mk1 - Clio mk1 overheating - advice please? - madf

Failed head Gasket

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Tue 26 Apr 2016 08:01
Clio mk1 - Clio mk1 overheating - advice please? - amyamandaallen

havent got any white smoke

dipstick oil black

looking inside rocker cover is black

expansion water just looks red, presume would be black?

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Tue 26 Apr 2016 08:53
Clio mk1 - Clio mk1 overheating - advice please? - elekie&a/c doctor

If there is a lot of gunge in the cooling system ,then you may have a flow problem.The rad may not be able to dissipate the heat.Remove the rad and lay it flat on the ground.Fill it with hot water and see if you have even heat across the core. May find the engine block also caked with crud.Sounds like the system needs a good flush.

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Tue 26 Apr 2016 09:47
Clio mk1 - Clio mk1 overheating - advice please? - amyamandaallen

Have had another look this morning and after running for about 25 mins last night, apart from the escape via the expansion cap it didnt lose any water.

That said Im now worried it is HGF because I had a look again inside the oil cap and theres some tiny amounts of gunge under the very top of the cap. Looking down in rocker its deffo black and so is the dipstick. I can look straight into the expansion resorvoir and its clear ( but a bit red/brown ) I can see tiny amounts of sheen if I look very closley but that could be antifreeze?

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