cover cill capillary action

has anyone else noticed that the cover cill is a definite problem where corrosion can start because it is fixed to the outer cill without a seal or an air gap. in my experience this will cause capillary action to occur and hold damp for a long time.
i have decided to fix mine with 3mm rubber washer at each screw hole therefore allowing water to escape and have airflow to dry it out.i am not concerned at ingress of water because of the drain holes in the bottom of the cover cill. the drain holes looked to have been punched from the outside on mine thus causing a small ridge to form on the inside and hold water. i have now punched them slightly out to allow water to drain freely. this may be a point worth noting for any one who wonders why they have rotten outer cills


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Hi, I think originally they had plastic inserts pushed into a square hole in the cill and the outer was screwed to them, which provided the small stand off. But that was 50 odd years ago and have disappeared in the mean time.;)



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I don't know how pattern cover sills fit, but mine leave a good gap in the space between the fixing points. As Colin says also the plastic inserts help with this.
i have just finished cleaning and etch priming the covers they do have a raised indentation for each screw giving about 3 mm of clearance along the majority of the cover but the outer cill and floorpan have been undersealed the screws have pulled the indents into thiis and thus closed the gap. the idea is good in a perfect world , but the bigger the gap within reason will allow any mud or debris to be washed out . seems i dont have any plastic inserts in mine . so the rubber washers i have inserted will hopefully perform the same function .