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Discussion Starter #1
Car is question:

2001 156 Sportwagon 1800 TS

Fired up the Alfa this evening and watched in horror as the temp gauge shot up close to the red. I turned the heater fan on but there was no hot air, the rad fan was going but it didnt seem to be doing anything...

After a while the heater warmed up and brought the temp down a bit but still above normal (90). Water level was checked and all was normal.

I went for a drive and the temp gauge went up to above 110 then down when I put the fan on, etc. It never overheated but was still never dropping below 100.

Here's the strange bit. When I felt the radiator it was stone cold. However the top and bottom pipes were warm, how does that work?? The top pipe was also under a fair amount of pressure. When I turned the engine off the top pipe got MUCH hotter, almost too hot to touch.

My first suspicion was the whole radiator was frozen and no water was getting through, the antifreeze was fairly diluted but wasn't frozen elsewhere (header tank). I bled the rad from the overflow and topped up with concentrated antifreeze, the water that came out of the bleed screw was hot and but the rad was still stone cold!! WTF?!

Ran car again but same symptoms, I just can't figure it out... :confused::cry:

Anyone??

Regards,
Iain
 

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sounds like either the thermostat has failed in the closed position which is unusual as they normally fail when open (an Uno 1300 I had did the same and I blew the head gasket after going to work and back for three days, same symptoms, cold rad and pressurized pipe)

or a failed water pump so the water is not being pumped round.

Thermostat easy and cheap, £40 and 30 mins, water pump more expensive as the cambelt has to come off to get to it, therefore complex and expensive £350 or so in belt

HTH
 

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Discussion Starter #3
Thanks for that HTH,

I replaced the 'stat this time last year but it has always been sticky since (temp goes up then down, etc). I don't really understand how the top pipe gets pressurised when the 'stat is closed? I thought there would be no water going through it? Can you explain?

I hope it ain't the waterpump, I only got the cambelt replaced in July! The heater works great so there must be water passing through the matrix, this says to be the pump is working but I could be wrong? Thoughts?

Thanks again,

Iain
 

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I'd have thought everything points to a frozen radiator. Not sure where you were bleeding warm water from - most rads don't have a bleed screw........

The top and bottom hoses will get warm by convection from the water heated by the engine - the heater is fed by water circulating before the thermostat opens so should get warm first. At -10C, a weak antifreeze solution won't be enough - the coolant may not freeze solid, but will be slushy, and resistant to flow - and remember that if you are driving the wind-chill factor will mean the air hitting your radiator will be effectively much colder....
 

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Not sure where you were bleeding warm water from - most rads don't have a bleed screw.......
I know the 2.0TS/2.5V6 rads have a bleed screw on the top, opposite end to the hoses.
Don't know about the 1.8 though, but I'd expect it to have one too.
 

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Discussion Starter #7
Thanks Boys! Alfaowner 1 - 0 Snow :thumbs:

Ran great today, I guess it was just the frozen rad, it eventually thawed. I'm antifreezed up to the max now so shouldn't happen again - lesson leant. :eek:

Thanks again,

Iain
 

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I know the 2.0TS/2.5V6 rads have a bleed screw on the top, opposite end to the hoses.
Don't know about the 1.8 though, but I'd expect it to have one too.

Must look closer at the rads......;)

Never noticed one, but never needed to.....tho can't see how OP could have bled warm water from a frozen rad.....never mind - at least the OP seems sorted now.:)
 

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the story points to a frozen rad.... never poor water in the rad !!! only cooling liquid
 

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its impossible for the stat to fail closed - good pointer at something else i the rubbish cooling system to be aware of though!!
 
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