I picked up the parts to do an interim oil change on my 118TSI (probably not necessary but something I've decided to do just for the first service interval). Everything was OK except they had given me a copper sump plug washer instead of a replacement plug. When I queried this at the spare parts counter I was told "we cut off the washer and replace it with a copper washer - it provides a better seal".
On getting home and on closer examination I could see that the original plug was a passivated (zinc coated?) steel plug with an aluminium washer and the sump was aluminium. Now this all makes sense from a corrosion point of view so I was reluctant to use a copper washer in combination with an aluminium sump which would leave the aluminium around the washer vulnerable to corrosion.
In the end I played safe, stuck with the procedure in VW's erwin and shelled out $5 for a replacement plug, fitted it after the oil change and torqued it to the specified 30Nm. However in the process I discovered that the replacement plug had a 19mm head whereas the factory fitted plug had an 18mm head!!
I have subsequently queried the use of copper washers with another dealership and was told "we always use a replacement plug". I'm interested now to know whether the fitting of copper washers is common or just something a particular dealer does. Given the potential for galvanic corrosion. I'd be surprised if it was endorsed by VW although you would probably get away with it in Australia given we don't salt the roads in winter like many european countries do.
For reference the washer and plug purchased had the following part numbers:
Copper sump plug washer N0138492
Sump plug with aluminium washer N90813202
On getting home and on closer examination I could see that the original plug was a passivated (zinc coated?) steel plug with an aluminium washer and the sump was aluminium. Now this all makes sense from a corrosion point of view so I was reluctant to use a copper washer in combination with an aluminium sump which would leave the aluminium around the washer vulnerable to corrosion.
In the end I played safe, stuck with the procedure in VW's erwin and shelled out $5 for a replacement plug, fitted it after the oil change and torqued it to the specified 30Nm. However in the process I discovered that the replacement plug had a 19mm head whereas the factory fitted plug had an 18mm head!!
I have subsequently queried the use of copper washers with another dealership and was told "we always use a replacement plug". I'm interested now to know whether the fitting of copper washers is common or just something a particular dealer does. Given the potential for galvanic corrosion. I'd be surprised if it was endorsed by VW although you would probably get away with it in Australia given we don't salt the roads in winter like many european countries do.
For reference the washer and plug purchased had the following part numbers:
Copper sump plug washer N0138492
Sump plug with aluminium washer N90813202
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