Easy way to add antifreeze

[womble]

I plan on keeping my boat in the water this coming winter and also plan to keep sailing.

I am considering adding a tee fitting to the raw water inlet hose together with a valve and a short piece of hose.

The plan would be after motoring back to the dock to put the tee'd piece of hose in a jug of antifreeze, close the raw water thru-hull and open the valve on the tee'd piece of hose in order to replace the raw water with antifreeze.

Does anyone see a problem with this setup?

I always close all thru hulls on my boat.

 

[Justin_NSA]

That's how ours is set up. We do it once in the water before we haul out with the crane. I don't see any difference.

 

[Davidasailor26]

My only concern would be how to displace the water in the intake line between the seacock and the tee. When the boat is kept on the hard that's not an issue - just open the seacock and it all runs out. But you'll need some way to get antifreeze into that section of hose and the upper part of the seacock.

 

[jviss]

MaineSail has an excellent article on his site, MarineHowTo, on the topic of antifreeze and winterizing boats; a must read.
https://marinehowto.com/freshwater-system-winterizing/
My concern is that you will dilute the pink stuff and not get the protection you need.

 

[womble]

My only concern would be how to displace the water in the intake line between the seacock and the tee. When the boat is kept on the hard that's not an issue - just open the seacock and it all runs out. But you'll need some way to get antifreeze into that section of hose and the upper part of the seacock.

Good point.

I think I could simply fill the tee line with antifreeze, hold it up above the waterline and open the seacock.

 

[Justin_NSA]

Would it actually displace the seawater or would you have to squeeze the jug to push it out?

 

[Len Ingalls]

I have this exact setup for winterizing on the hard.
Make sure you install the antifreeze tee between the seacock & the raw water filter inlet.
This way the raw water filter will be filled with A/F as well as the rest of the R/W system.
Close seacock,open tee valve,run engine til lots of pink RV A/F out the exhaust,stop engine,close tee valve,open seacock.
The raw water in seacock will drain to waterline level in a minute & you can close seacock if desired.
This uses about 1/2 jug (2L) of A/F = $2 each time.


Alternatively,you can blow into the tee hose at the A/F jug end & blow the water out the seacock & then close it.
/ Len

 

[womble]

Would it actually displace the seawater or would you have to squeeze the jug to push it out?

I'm fairly optimistic gravity should do it. I've found it to be a very dependable force.

Or like Len says, I could just blow air while closing the seacock.