Another overheating type thread (sorry)

[matto]

Ok I've done a search but have not been able to completely find answers to the questions I have regarding why my little e30 looked like a hissing dragon thing when I parked up at work today (steam coming out of the kidneys, actually looked kinda cool )

1. Is there a short term fix for a thermostat that appears to have failed in the closed position? Very Hot top hose, cold bottom hose, heater working fine, water fizzing out of somewhere around the top of the rad when it's been stationary for a while.

2. Is the fan controlled by the thermostat ie. does it engage the coupling somehow? (it failed the newspaper test) Or is that related to question 3...

3. Even when the rad is bubbling away the in car temp gauge only shows just above normal, I assume this is due to the failed thermostat and hot water not getting to the sensor?

4. Or is my diagnosis crap and it's something else entirely?

Cheers in advance

edit: whoops, m40 316i 1989!!

[zaust]

Sound's more like a failed rad to me.

[matto]

Hmm, really? That wouldn't be too bad as I got given a non leaking m40 rad for free a while back... just to add a bit more detail, I've only noticed this now the weather has got better, the car was fine while it was cold, but the previous owner did have a huge half full evian bottle in the boot which made me wonder if the car was going to stop in a huge cloud of steam at some point But until today I've not had a whiff of a problem.

[matto]

Gah, time for the embarrassed emote...



Top hose is hot and so is the bottom hose... however unsurprisingly the hose from the bottom of the expansion tank that I had just topped up was cold. I'm sure the top and bottom hoses on my old 205 were on the same side (hastely making excuses now)