How are you guys sucking antifreeze into the block?

[FMSKI]

5 years ago, the '97 TSC project went into a shop for hull paint (1 month they'd be done). That Sept, I pulled just 4L of RV into the GT40 engine. Well it was finished the following spring.

But that winter we had a wicked cold snap. Cold was so bad, the plant I worked at had the propane back-up freeze, lost fuel they dropped the big boiler. Couldn't restart and froze the steam tracing and water lines. $M in damage.

My GT40 wasn't winterized properly by the shop, they didn't drain the block at all. It survived ! that's when i did the freezer test and found 4L was actually enough.

[Brucetheshark]

Owner manuals state to drain, then add antifreeze "to dilute any remaining pockets of water". Be careful with RV AF, it's made for drain traps and may not be compatible with the motor seals like auto AF. If you lower the trailer tongue to get the motor level, draining will get almost all the water. Also, i you start with the lowest block drain (assuming you didn't get the motor totally level), it will create a siphon effect such that when you remove the rest of the drain plugs, you won't get much water if any. Another note; the T-stat on our boats will only barely crack open due to receiving cold lake (or hose) water, versus an auto engine that recirculates the coolant, therefore sucking in AF via hose may not get to the heads. If you really want to safeguard super cold winters, remove the T-stat and add AF into the housing, it's easy. Other posts mentioned not to add the tiny petcock valves, they're right, those have a tiny diameter that will clog with rust and seaweed. If you open a drain plug and don't get much water, stick a wire into it to clear debris. I worked at Ford Motor Co. in the 80's - 90's and sat near the Marine Engine guys.... I bugged them a lot .