Right, I finally got around to doing this mod this weekend, was reasonably straight forward thanks to Westy's excellent guide. Only one question, I need a one way valve for the brake hose off the end of the mani (BAM engine), the ID of the hose looks to be 12mm, would this do the job: Marine Non Return Valve. 12mm (One Way). Good Quality. Boat | eBay I can't find any others that look a decent quality, where have you chaps sourced yours from?