polo sump problem - womble

When I had my 98 VW Polo 1.4 serviced last year at a VW dealer they stripped the sump thread when changing the oil.They repaired the sump with a Heli-Coil.I have recently changed the oil myself and found that they had put in the original sump plug which had about 3 good turns of thread left on it.I replaced this with a new plug.Last year the garage told me this was a common problem because the sump is made of aluminium and the plug is steel.Considering this was only the fourth service and had only been worked on by trained VW technicians,I found the "wear and tear" explanation a bit poor.I think the sump plug had been overtightened causing the thread to strip.Has anyone else had a similar problem?
polo sump problem - Andrew Moorey (Tune-Up)
Doesnt only affect VW's. So many times I have to fight with sump bungs because the Rock Ape before me has groisted the plug up too tight. Simply use a new washer and nip the bung up. 25Nm is usually sufficient in most cases.

Happiness is a T70 at full chat!
polo sump problem - bertj
Just to add to Andrew Moorey's comments:
It is ESSENTIAL to use a new copper washer on VW sump plugs (and probably most other vehicles) otherwise you end up trying to overtighten the plug to make it seal.
polo sump problem - martint123
It's not as though there's 100psi of oil pressure in there is it.
If a plastic container holds five liters and doesn't leak in my boot after bouncing around for 6 months, why does **** fit or whoever swing on a wrench tightening the sump plug???

polo sump problem - bafta
Caused by over-tightening. Professional incompetence. The point Martin makes is valid. Some fitters (I hesitate to call them mechanics) should not be allowed near a vehicle!
polo sump problem - 9000
I took my vectra to a national fast fit chain for an oil change about 6 months ago. A few weeks ago I took it for another, this time at a small independent tyre place. They informed me that they were unable to do the work as the plug was just spinning and would not come out. I returned to the place which had done the previous oil change and to cut a long story short the area manager sent me a fax stating that he accepted the threads could have been damaged when they changed the oil but similarly the second garage could have done the damage when attempting to undo the plug. He offered to cover half the cost of having a helicoil fitted and invited me to bring the car in to one of his branches for this to be done.
I have since paid for the sump to be helicoiled at a cost of £100 from a 3rd garage as I did not trust any of the other two to work on my car.

It seems fairly obvious that this damage can only be caused by over tightening and therefore would be entirely the fault of the first garage- I'm really annoyed about this as through no fault of my own I have picked up a £100 bill. I have not yet replied to his offer as I am still considering my position. Can anyone suggest a best course of action? Thanks

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