We always do it on the hard and for us, we just take the intake hose from the strainer and dunk it into a 5 gallon pail filled with the -100 antifreeze. Once it starts spitting out the exhaust...DONE
Knuckle47, no offense please, but this is a common misnomer, and I could type 500-1,000 words of caution re; this subject!
Now if you are speaking in terms of the exhaust ONLY, then I would tend to be more in agreement.
But for an engine block with a stat in place...... I'd have to disagree!
Ayuh,.... Or ya can just Drain the raw water side,....
Air just don't freeze....
Bingo!
No, my Luhr's doesn't have strainers. I'll simply do the 5 gal. bucket filled with the pink antifreeze like I do while she's still in the water. Another question, after you run the antifreeze through and put her on the hard, do most of you leave the sea cocks closed or opened?
Always open the drains afterwards, and probe them with a wire or ___ to remove any rust scale that may prevent all from draining.
If you leave them open, place a note at the helm.... possibly wired to the keys.
Nightstalker, I'd suggest that you consider just plain ole air over the risk of diluted anti-freeze, and here's a brief description of why:
A raw water cooled engine system pulls in much more water than what actual engine cooling demands are. Most is being directed to and on out the exhaust system.
The thermostat system allows only that coolant (raw water in this case) to enter the engine as the thermostat dictates..... sort of a "on-demand" basis, so to speak.
Again.... most spent sea water is exiting the exhaust system.... not entering the engine!
There are those who attempt to bring an anti-freeze mixture into the engine via the raw water pump system, and in hopes that the thermostat opened enough for a full exchange.
The misnomer: They see anti-freeze exiting the exhaust, and think that they got all, including the engine/cylinder heads!
Not so... due to the previous explanation!
The amount of coolant (in this case the anti-freeze) mostly by-passed the engine demands, exiting out the exhaust......, thus giving the owner a false sense that this anti-freeze has properly
exchanged itself for the raw water that is within the cooling jackets.
It has NOT!
At least not while the thermostat is still in position, and even this requires a duration of run time!
(if you were to do this, pull the plugs first, and drain what sea water is in there!)
I could NEVER recommend this to anyone.... unless they were to know precisely what they're doing.
(there is a method, but it is much more involved, and quite frankly, not worth it.)
If Hell Bent on leaving anti-freeze within the cooling jackets, the most sure fired method would be to completely drain the block, probe the ports, re-install the drains, remove the thermostat and introduce the anti-freeze via the thermostat port.
This works for engines whereby the T stat is above all else in elevation.
But again.... AIR will not freeze and expand causing damage (as Bondo mentions).
The added anti-corrosion value of anti-freeze being in the jackets for the winter duration, is of no where near the importance of preventing freeze damage.
Any rust scale that is present, is already at work, and the otherwise anti-corrosion gain is very little, IMO.
Your call!
