scooper321
Well-Known Member
I've stared at the engine diagrams in the Mercruiser parts manuals enough that I'm confused.
My 2003 320 Sundancer has the 5.7L 350 MAG MPI Horizon engines. They are Fresh Water Cooled, but from what I've been reading, some FWC engines are only half FWC systems while others are 100% FWC. I have heat exchangers on the rear of my engines, near the mufflers. And based on a conversation with my local service department, this seems to imply that I have a full FWC system. Is that a correct assumption? What's the actual difference between a half and fully FWC Mercruiser system?
I know that even fresh-water cooled systems use raw water to a degree. But in a fully FWC system, are any engine components DIRECTLY exposed to raw water? Or, is it just the indirect exposure to raw water and it's vapors via the underwater exhaust that presents the danger to a FWC system?
Finally, what components of the exhaust are really in jeopardy in a FWC system? It seems like the manifolds and risers should be pretty "far away" from the raw water to be subjected to any corrosion. What am I missing?
Thanks,
My 2003 320 Sundancer has the 5.7L 350 MAG MPI Horizon engines. They are Fresh Water Cooled, but from what I've been reading, some FWC engines are only half FWC systems while others are 100% FWC. I have heat exchangers on the rear of my engines, near the mufflers. And based on a conversation with my local service department, this seems to imply that I have a full FWC system. Is that a correct assumption? What's the actual difference between a half and fully FWC Mercruiser system?
I know that even fresh-water cooled systems use raw water to a degree. But in a fully FWC system, are any engine components DIRECTLY exposed to raw water? Or, is it just the indirect exposure to raw water and it's vapors via the underwater exhaust that presents the danger to a FWC system?
Finally, what components of the exhaust are really in jeopardy in a FWC system? It seems like the manifolds and risers should be pretty "far away" from the raw water to be subjected to any corrosion. What am I missing?
Thanks,