Help, winterizing and trying to get antifreeze into drained block

[jaywidhalm]

I too only just drain...no antifreeze, did it for years with my Wellcraft I/O and now my Supra...never had an issue and I live where we get a good solid week of -20 F weather.

[docdrs]

A closed water cooling system is a completely different situation. You cannot lump it in with the standard open loop systems in the majority of freshwater inboards which have a thermostat for optimal performance.

I always drain everything incl muffler and heater. Just stating the facts about trying to winterize your system properly without draining it. I would never recommend anyone to do it this way unless they are 100% familiar with how the cooling system works. Otherwise you are just lucky if something doesn't crack. My boats experiences long spells of -20 and colder so I can't rely on luck.

[michael hunter]

Freezing is not the only reason to add antifreeze . It also helps with rust and scale inside the block. I feel that its better to keep wet parts wet . Letting things cycle wet then dry then wet again puts added stress IMO. Once you have drained the water it only takes 5 min to pour 15 dollars of antifreeze in the raw water hose that goes to the T stat housing. It only takes 1 time to cause thousands in damage why take a chance?

[chris young]

Has any of you who only drain ever had an issue or heard of one that damaged your RWP? I've read elsewhere that you should bump the motor a few times to clear it. I didn't do this as the last thing it had running through it was antifreeze so I think I'm covered.

[92SupraComp]

if you run anti freeze your fine. If you drain, it helps to bump it over. I have to run my CC and give it a good rev to blast the water out of the exhaust. The hoses go down along the stringers inside the bilge and then go up hill into a big IvertaFLow by Vernay Silencer. It uses the water as a baffle, and boy that thing keeps a lot of water in the exhaust hoses...