There are two different issues here Dave causing a little confusion I think.
The internal nicasil plating on the cylinder bore is removed using a special process involving acid dipping. So, in theory, I guess this could be done an infinite number of times, assuming the cylinder bore is kept within the required tolerances, and it shouldn't be an issue for you to worry about.
The problem with these cylinders was that they had previously been replated multiple times by a well known company who we no longer deal with. This is due to quality control issues relating to the fact that when they prepare the cylinders they skim grind the top of the cylinder. In doing this the deck height of the cylinder is therefore slightly reduced every time they replate a cylinder.
If the cylinder has only been replated a couple of times, even by this company, this generally isn't an issue. However the more times a cylinder is replated by them obviously the smaller it gets because each time the deck height is reduced slightly. Therefore there comes a point in time when the deck height is reduced to such a point that the compression and squish will be affected. This increases the likelihood of a seizure if the height is not returned back to standard by the use of a thicker than standard base gasket.
As I have already stated this is not something we would generally advise doing. Therefore cylinders done multiple times by this company reach a point where they are in effect scrap as they cannot be used because of the reduced deck height.
We are therefore very careful to always check cylinders that come in for replating with serial numbers from this company on them and to check the deck height before doing any work. This was done with these cylinders and one was found to already be 1.5mm smaller than standard because of the number of replates that had been done on it by this company. It was therefore advised that the cylinder should not be replated a further time.
Just so you know we have also seen cylinders from this company where the bores have been too tight and/or they have not been round, so problems with their services are not just limited to deck height issues.
By the way I notice the seller has amended the description slightly on the auction now.
Jo
www.apexleisure.co.uk