Thats ok was it not mermaid that said how good the engine was and that it had been well looked after?
I think if you bleed the air out and have the batttery fully charged I think it will start the engine does not need rebuilding if you can got 28knots then there not much wrong with the lump its the starting thats the issue thinking back if mermaid did bleed it and you had clive bleed it again I am thnk the air is getting in some were I would bleed it again and have both bateries charged the engine needs to crank quicker than it did yesterday if you bleed it again and get it started if you leave it a couple of days and it want start again then you will have to find the leak
mark