I've been down this path and found out you have to use the Volvo yellow coolant as it has a corrosion inhibitor in it. The engines after about year 2000 do not have anodes and the reason is Volvo use this coolant to avoid corrosion. Drain your coolant and flush out with fresh water then add Volvo yellow coolant or equivalent as I don't know of others. André in Sydney

Oh! Muchas gracias por compartir, tengo ese mismo motor con 13 años así que cruzo los dedos. Espero que hayas podido finalmente solucionar y puedas disfrutar después de todo lo pasado. Saludos.

Seems like there are a lot of us who have been through this. The aluminium manifold is a ticking time bomb. Glad you were able to sort it out. I'm having the manifold welded here in the Dominican Republic where this issue was discovered after I left the boat here for 9 months. I'm also planning to add a Y valve so I can routinely give the cooling side a fresh water flush.

my name is werner and i'm also a sailor. Many thanks for your video, it helped me a lot - especially the names of the companies from which you ordered the spare parts. werner from southern germany

Great video nice and clear.

I agree with @Appleman that it’s not your fault and this damage is not from the coolant used. The corrosion was from aft side. Yes? The use of these quite short mixing elbows combined with the typical water lift exhaust system causes backsplash of raw water while running under certain conditions. On my friend’s Perkins M30 with an iron exhaust manifold, same thing, just more gradual corrosion than the aluminum manifold on the VP version of same engine. A look at used manifold market shows a chronic problem. In other words, because of overly short, non-riser elbows, the manifolds have become wear items on a great variety of VP and perkins engines small and larger. Getting a riser type mixing elbow on there should cure this. Perhaps a lower restriction exhaust system would help slow it. Sending half the raw water from exchanger directly overboard would help reduce back pressure surges.

Love the video's just subscribe but i notice you have not put one up for a good period of time hope every thing is ok in these difficult times

I don't think it was your fault because that is where seawater sits when the engine is stopped. This has happened to both my engines