got a job on a Baxi 130he?

got a job on a 130he and it's been fine for about 8 years without a problem, but client said that it gave out a dull thump after running the hot water for a short period, I've dismantled it and it's in solid condition if a little dirty!!! several things have failed however ie, the burner gauze has come adrift ( suspected that was the thumping sound!) spark electrodes have crumbled, central insulation plates have seen better days and most of the strip seals ie combustion box door seal etc have perished, all these items are on order to replace and I suspect that the lack of annual maintenance has just brought about the failure but, do I need to look further???