I agree and don't drain my engine unless I plan to lay it up with
anti-freeze.

As I mentioned in my reply to Richard, I have provisions for pumping
anti-freeze into the cooling jacket, if I were in a colder climate or didn't
keep a heater going in the winter.

Steve
s/v Good Intentions


"Rich Hampel" wrote in message
...
Sorry but 'drying' a cast iron engine will greatly shorten the service
life. What happens is that the cast iron begins to form 'slab rust'
.... huge plateletts of ferric rust that propagates between the natural
'laps' of the casting. Cast iron, due to the way it cools when molded
is similar to an 'onion' ... and the ferric corrosion (usual severe
rust) will rapidly develop between the 'laps' and form ferric rust ,
develop extreme pressure between the natural 'laps' and begin to
destroy the casting. If you keep the engine 'wet' (using such things
as antifreeze with rust inhibiters0 this process is greatly retarded.
Cast iron is a good metal vs. sea water as the high operating
temperature produces 'ferrous' rust ... a blue/black oxide that
actually protects against ferric rust.

The moral of this story is dont 'air-dry' your engine by draining all
the water out ..... put in a mixture of water and antifreeze - and
this will keep the protective 'ferrous' layer intact. Otherwise,
expect to develop pin holes and leaks in short order.

hope this helps.

I used to have a raw water cooled engine, and used to winterize by
pumping antifreeze through it, and closing the cocks. Let the engine
run to temperature so you circulate the antifreeze. Inboards tend to
stay a little warmer since they are closer to the water, which tends to
retain temperature, and protected in some way from the elements. I
would doubt that the first night or two in high 20s will cause it to
crack, but why strain it? I'd plumb a second connection to the
raw-water intake so you can easily and quickly pump some antifreeze
through it, easily enough to do it every time you get back from a trip.
You may also consider a "block heater" type device--I used one in my
car, which did not have an integral one, in -40 degrees. That one was
magnetic, designed for lawn-mower sized equipment, but it worked well
enough: plugged it in, and it attached magnetically to the engine. I
don't know how well it would work against freezing, and I doubt that
you can find one that is appropriate for marine use, so take that for
what you paid for it.

mickey

Simple answer to that is to add valved tee connectionIn to the intake
line and drain cocks teed to a common. Just drain the raw to the
bilge, saving if antifreeze into a bucket. simply, suck the antifreeze
back in when shutting down.


article , Steve
wrote:

I agree and don't drain my engine unless I plan to lay it up with
anti-freeze.

As I mentioned in my reply to Richard, I have provisions for pumping
anti-freeze into the cooling jacket, if I were in a colder climate or didn't
keep a heater going in the winter.

Steve
s/v Good Intentions


"Rich Hampel" wrote in message
...
Sorry but 'drying' a cast iron engine will greatly shorten the service
life. What happens is that the cast iron begins to form 'slab rust'
.... huge plateletts of ferric rust that propagates between the natural
'laps' of the casting. Cast iron, due to the way it cools when molded
is similar to an 'onion' ... and the ferric corrosion (usual severe
rust) will rapidly develop between the 'laps' and form ferric rust ,
develop extreme pressure between the natural 'laps' and begin to
destroy the casting. If you keep the engine 'wet' (using such things
as antifreeze with rust inhibiters0 this process is greatly retarded.
Cast iron is a good metal vs. sea water as the high operating
temperature produces 'ferrous' rust ... a blue/black oxide that
actually protects against ferric rust.

The moral of this story is dont 'air-dry' your engine by draining all
the water out ..... put in a mixture of water and antifreeze - and
this will keep the protective 'ferrous' layer intact. Otherwise,
expect to develop pin holes and leaks in short order.

hope this helps.