I plan on doing my own winterizing this year. Marina just charging too much. I have a 1978 Cruisers Villa Vee with twin GM V-8's raw water cooled , its also straight inboards.
My plan is to drain manifolds and block for both engines. Then remove the hose from the thru-hull and place in a bucket of RV anti-freeze. Run until it comes out the exhaust, then fog the engine til it stalls.
I'm a little concerned that with the raw water pickup hose in the pail some air will be in the system before the anti-freeze is pulled up. Is this a problem? I plan on pouring some anti-freeze into the hose before placing in the bucket, but think that would just run back into the pail.