If I remember correctly 200 and 300 TDI header tank coolant levels are lower than the coolant level in a cylinder head and thermostat housing
So now you have removed that pipe you have introduces an airlock into the thermostat housing/cylinder head
You will have to follow the correct procedure to refill and bleed the system then roadtest until the stat opens
So now you have removed that pipe you have introduces an airlock into the thermostat housing/cylinder head
You will have to follow the correct procedure to refill and bleed the system then roadtest until the stat opens
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Dr Strangeglove
Well-Known Member
That plug looks like it has seen better days. I would seriously consider changing it for a brass plug to reduce the likelihood of problems in the future. The plastic ones are notorious for binding and having to be cut out piece by piece and bits falling into the thermostat housing whilst doing it.
I think I have seen a thread somewhere that had a domestic radiator bleed plug used instead of the plastic plug. This was the type you can get from plumbers merchants or screwfix etc. The advantage is it has that little bleed screw and also cheap - plus you can pick them up at screwfix etc do usually off the shelf and local. Please note I have not done this myself so can't give you first hand experience, but perhaps others on here have and can comment?
I think I have seen a thread somewhere that had a domestic radiator bleed plug used instead of the plastic plug. This was the type you can get from plumbers merchants or screwfix etc. The advantage is it has that little bleed screw and also cheap - plus you can pick them up at screwfix etc do usually off the shelf and local. Please note I have not done this myself so can't give you first hand experience, but perhaps others on here have and can comment?
Dr Strangeglove
Well-Known Member
This is a similar thing to what I saw. I think they are 1/2" taper thread so tighten with caution, but cheap with a bleed screw - you just need a radiator bleed key to open the vent.
Yes I can’t get it out
You can try an impact gun.
If that fails a small chisel and a light hammer, don't damage the housing as they are around £80 to replace.
Here is the plug .... https://www.ebay.co.uk/itm/201949613615
If that fails a small chisel and a light hammer, don't damage the housing as they are around £80 to replace.
Here is the plug .... https://www.ebay.co.uk/itm/201949613615
@Harry2000
I went and looked at mine after @lynall said that ... when full (as in over full) the water level is above the head, however there is a valve so you need to top up the rad then the thermo housing as this is above the radiator.
So @lynall is right and I was wrong ...
Dr Strangeglove
Well-Known Member
When mine was stuck I cut the hexagonal section deeper by cutting away the flange to the same shape as the upper bit. This made a much deeper hex section to get a sparkplug socket on. I used a decent braker bar and just rocked it backwards and forwards to loosen it.
I originally thought I was just going to shear the top off, but it actually came out. I was really pleased as I didn't want to have to pick it out. There was still some residue in the threads but I managed to scrape them out with a scriber.
Good luck with it.
I originally thought I was just going to shear the top off, but it actually came out. I was really pleased as I didn't want to have to pick it out. There was still some residue in the threads but I managed to scrape them out with a scriber.
Good luck with it.
robbie the greatl
Active Member
theres a black plastic bleed screw on mine near heater pipes
