Leaking bleed screw on thermostat housing

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tha881
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Location: Kent

Post Thu Oct 14, 2021 8:58 pm

Need some help please, I've just filled my coolant on my m20b25, filled each hose as I went until the coolant came out from the bleed screw. Then I nipped it up. However once i started the car there is a slow stream form the bleed screw. It's a brand new bleed screw aswell. I cant get it to stop.

Should i have kept the old limescaled one!?
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onthames
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Post Thu Oct 14, 2021 10:22 pm

Teflon tape may be a temporary fix, or Loctite liquid PTFE
tha881
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Post Fri Oct 15, 2021 6:06 am

Thanks, although im not certain that will work as the bleed screw has a smooth part. I think I am going to need a new thermostat housing cover, luckily they arent that expensive.

How much coolant am I going to lose by changing the cover in situ? Is there a place I can try and drain enough off so it will not make a huge mess?
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tha881
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Location: Kent

Post Fri Oct 15, 2021 2:06 pm

Made a quick call to the stealer this morning and they had the parts in by lunchtime. It is clear now that you only need to tighten enough for the nipple at the end of the screw to seat in the hole, fully tight will leave around 7mm of thread of protruding from the cover like so

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