BoatBanter.com - View Single Post

Wayne.B

On Mon, 08 Oct 2007 22:05:17 -0500, lid wrote:

Looking back now, I'd gladly pay the extra $1000 if the benefits are as
described. New manifolds and risers run about $6-700 also.

I sure someone will correct me if I'm wrong but, IIRC, the fresh water
cools only the engine. Salt water is still used to cool the fresh
water (in the heat exchanger). It is pumped in from the sea with the
standard water pump in the lower unit and returns to the sea by way of
the exhaust manifold(s), just like standard cooling. So if you're
thinking you'd be saving the manifolds from seawater's rust and
corrosion, you'd be wrong (if I'm right in my recollection).

It depends. Some FWC systems cool the manifolds with coolant, others
with raw water. The risers/elbows still see raw water regardless.
Obviously if the manifolds are still being cooled with raw water their
life expectancy will not be increased by FWC, only the block and
heads.