Having just done a coolant drain and flush, the original red radiator drain tap was looking a bit weathered and brittle, plus discoloured through age. I removed it, and the washer below the head was quite badly corroded.
The red drain tap and washer are NLS from Vauxhall, and both have been superceeded by a black version (not requiring a washer under the head). Both my local VX dealers have no stock of the black version, and have given 'several days' to supply one. Been through previous topics on here and some suggest the black version doesn't seal as well as the original red one.
To get the car back mobile, I have bought a replacement red one from ECP, but it doesn't come with a replacement washer. It is exactly the same dimensions as the original VX version I removed.
Might seem like a small problem, but to get the correct amount of compression on the O rings to seal the drain without damaging them, it requires the washer under the head to get the correct spacing.
The original appears to be a steel washer with grooves from the centre to the outside edge, but is badly rusted so I don't want to reuse it. As the original washer is NLS, what is the consensus about a replacement washer? Steel, aluminium, fibre, or copper? The coolant sealing is theoretically done by the O rings, so is the purpose of the washer like a lock washer or just for correct positioning of the O rings to create the coolant seal when shut?
I can't believe a simple washer is the subject of this topic
, but I'd rather get it right first time, rather than risk having a leak and loosing the relatively 'expensive' GM coolant unnessecarily.
So what type of washer is thought to be the best for this purpose?
TIA...
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Topic: Red radiator drain plug / tap (Read 983 times)