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Not worth servicing, chuck it out, I'll help you and take it off your hands to save you the trouble Are you aware that manuals with maintenance details are downloadable from Duncan Rogers ?https://www.duncanrogers.com/https://www.duncanrogers.com/literature/62%20305%20052%2012%20ed00%20RLR%2015%20%C3%A0%2040%20EN.pdf