Life in preservation is mostly better for a vehicle than that experienced whilst running in regular service however there can be new challenges to manage to ensure reliable operation continues for many years.
Being of riveted aluminium construction the 620/720 cars are notorious for rain water entering the bodies via joins, rivets and cracks and to combat this the roof has now received 2 good coats of roof silver to seal the gaps and also reflect the heat of the sun. The exhaust and fan openings in the middle of a 620 power car roof unfortunately cant be sealed with paint so different controls are being put in place to avoid damage and deterioration.
The fan assemblies have an unfortunate design feature which captures rain water when not used. In daily service the fans turned regularly and ejected any water but when in outdoor stationary storage they become very effective water collectors.
To initially improve the situation the water was first sponged out..
…and the inside of the “bowl” scraped to remove surface rust.
The centre and surround were then wire brushed, the debris removed and the metal treated with rust convertor.
A coat of rust guard primer was applied to seal all surfaces and the bowl has been temporarily covered until the next visit when the second part of the fix will be implemented.
To protect the engine from rain water entering via the stacks exhaust rain flap covers have also been put in place temporarily pending final measurements and adjustments to ensure everything is “in gauge”.
Even with rain forecast again for the coming weeks we can rest easy knowing these 2 issues are under control.
