Hi All,

I have the 1.4 aex engine. I've replaced the thermostat (twice), and its has had a new housing a couple of years back when the head gasket was done. It still goes down to 70 degrees when on the motorway and up to 90 in town. I know (as this has been said already) that its the thermostat staying a bit open, but what is the solution? I have put 2 thermostats in already. Is there some way that the pin is not closing properly that means its staying open / not lining up? The bridge housing is fine from what i can see, and have compared it to a new bridge housing to double check. One thing i did notice is where the other end of the thermostat sits in the engine, its not a tight fit in there, so perhaps when it closes (i.e pin gets shorter) its not lining up properly with the end piece, and its dropping slightly? If that makes sense?!

When i took the first thermostat out, and undid the bolts, the outer housing piece was pushing away from the main body housing, suggesting it wasn't fully shut. Why would this keep happening? When i installed the thermostat, it worked right to begin with, as temperature sat at 85 ish on the motorway, but then once its done a complete cycle of heating up and then cooling down, it seems to stop working properly. I have done a lot of research, and it seems the overcooling is a common problem once a new thermostat and housing has been put in, but seems there's no solution for the overcooling as people have replaced both the housing and the thermostat which hasn't worked.........anyone know what is going on in housing that causes this?!

Thanks in advance and apologies for the long post!

bump! :)

hello, dont suppose you got these pictures still have you? haha!

Yeh Pics again would be great as have had this where bottom hose freezing, no fans and throwing coolant everywhere, fitted new stat, okay for a cple of journey's now back to good old spugh!

Hey

Without stealing anyone's thunder I did this swap the other day. I spent a bit looking for a how too with some pics and was gutted this guide was down so i took my own, hope you dont mind!

First off I would recommend taking the whole plastic unit off, its only a matter of 3 bolts and a load of hose clips. Just made lining up and attaching the thermostat hell of a lot easier.....

Broken elbow compared to new elbow.....

Thermostat sat in elbow

Thermostat sat in unit

Thermostat (held) in

Its a really tight fit which is why I say take the whole thing off because then I could clamp it with some mole grips and make sure I hadn't caught the seal as I was doing the screws up.

Last thing...the one I took out was put in the other way around to the pics I took. When I was getting the parts from VW I checked with them which way it should be and its as the pics are.....the pin on the thermostat sits in the little chamber in the middle of the elbow.

Hope this helps :-)

Ellie

Hi guys, I've got a 1.4 8v 2000 6n. I've just changed the thermostat and the bridge bit that always breaks. Both pipes are the same temperature, so the stat is opening, it runs up to temp then after about 5mins it begins to creep up if i put the blowers on hot it stays at running temp, as soon as there off it begins to creep up.

Any ideas would be much appreciated. Cheers louis.

I've got this problem atm, I've replaced the stat, housing and temp sensor and it's still not fixed.. Any other known causes?