VicS
Well-Known Member
It's a D2 55, thanks everyone for helpful advice and even some science. Crikey you folks are knowledgeable!
Still not sure how much propylene glycol I am buying for freshwater systemthanks.! Yacht 44 foot, aft and rear tanks, two heads both with shower.
Early versions of the D2-55 would have been supplied with green "Volvo Penta Coolant" The (yellow) "Volvo Penta Coolant VCS" was not introduced until May 2010. Engines supplied after that date may well have been supplied with the yellow VCS coolant.
The owners manual I have is a 2009 edition. At the moment the VP manuals website seems to be broken so I cannot look for any later edition to see if the VCS coolant is specified in them.
If your engine should have the yellow coolant but in fact contains the green coolant ( or any other conventional non OAT type of antifreeze) You have two choices Either continue to use the same type or chemically clean the system before switching to the yellow OAT type. The chemical clean uses oxalic acid, but I have no details apart from the part number for the cleaning kit, # 21467920. Dealers charge an arm and a leg to carry out this clean.
Cannot help with the quantity of propylene glycol you will need for the domestic freshwater system. It will depend on the capacity of the system, rather than the length of the yacht.
Draining the system thoroughly is probably the most sensible option, certainly the cheapest. You will have to drain out the propylene glycol anyway at the end of the winter.