EGR Valve Coolant Leak

mibo

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Had a bad day with the EGR Valve today.

I took it off to clean it and when I reinstalled it, some threads sheared off which means it didn't fit back fully torqued up. This caused the entire coolant reservoir to dump out the EGR valve. Is there supposed to be coolant within that part of the system?
 

mioba

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Ouch.

I have got into a habbit of wire brushing threads whenever i reinstall anything and a bit of anti seize paste. Always working the bolt in by hand first.

You can normally feel some resistance when chewing the threads.

A torque wrench is essential. Ham fists will kill threads.
 
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mibo

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Ouch.

I have got into a habbit of wire brushing threads whenever i reinstall anything and a bit of anti seize paste. Always working the bolt in by hand first.

You can normally feel some resistance when chewing the threads.

A torque wrench is essential. Ham fists will kill threads.

I did use anti seize paste going back in, and I only had about 5 degrees of spanner turn available so pretty sure it happened when taking out; it was hard to get off. I'm hoping to get a nut under the flange :-/
 

Uncle Benz

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Oh dear. Did you use a new gasket? You must use a new gasket. If you re-use the original it will leak. I guarantee it.
 
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mibo

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Oh dear. Did you use a new gasket? You must use a new gasket. If you re-use the original it will leak. I guarantee it.

Nope same gasket and it definitely leaked! I was surprised coolant would be in there though?
 

mioba

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Whenever you seperate components sealed by a gasket it is prudent to change the gasket. For the sake of a few quid and all the work gone into the process, the last thing you want is to button it all up and have a leak.
 

Uncle Benz

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These metal shim gaskets are one time only. If I had a pound for everytime I’ve seen someone re-use and it’s leaked…. The knee-jerk reaction is always to try tightening the bolts more.
 
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mibo

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It got worse, I removed the EGR Valve and the EGR Valve flange cracked off on the other bolt!
 
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mibo

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Yes, some EGR s are water-cooled.

Taking it back off I can see the hole the water goes through which now makes sense. I thought it was coming from the air flow pipes which really confused me!
 
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mibo

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Jesus Christ, I've just put a new one on and its ****ing out coolant too
 

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