Offshoreonly.com - Fresh Water Flush Connections on 496HO

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Boat is an 08 32 Sunsation SSR with 496 HO’s.
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I do not boat in salt water so I have never used these flush fittings. I will not be in heated storage for the first time this winter so want to make sure I get rv antifreeze everywhere needed. I never liked the idea of pulling it up from the lower unit, if I use a pump and push rv antifreeze into these flush fittings will it circulate throughout the entire raw water system? There is a tag hanging on the flush connection that says “do not run engine while flushing damage may occur”. So engines would be off.