winterizing 454's

[topnote]

While reading directions to remove water from these 1985 era gas 454 engines I see the following instructions...

"Drain the Heat exchanger, manifolds, and oil cooler of sea water. There are two plugs, one for antifreeze and the other for seawater."

Can anyone share where these seawater plugs are...pictures or description?
thanks

 

[northern]

They are 1/4" plugs in the small heat exchangers located at one end.
On my engines one is vertical beside the transmission and one horizontal under the large heat exchanger
Not sure if this how one should winterize a 454 but I do the following
Drain the mufflers of sea water
Open the hull through valve to drain the water in the line to the strainer
Suck out the sea water in the strainer
Close the hull through valve
Disconnect the coil wire between the coil and distributor cap
Turn over the engine and pour in 4 gallons of pink propylene glycol into strainer
Let mufflers drain of pink
Open the through hull valve

This is year 2 of winterizing for me. Boat is located on land and it got to 15F last winter for a few days.

 

[mnm99]

I'm not sure about the heat exchanger, but your block should have a couple plugs, check on the raw water pump. I would just look around and pull whatever plugs have raw water in it. drain and put all the plugs back. Do you have a sea strainer? If so go buy like 7 gallons of -60, have someone start the engine and start pouring in one gallon after another. Shut down after your done with all 7.

 

[wayne0]

Don't need 7 gal. 4 is fine.

 

[rondds]

Minor point...your boat info says 454 Mercruisers. Those are not Mercruisers - and it's not just the color that's wrong. COMPLETELY different exhaust manifold and elbow design. That looks like a Crusader.

Could make a difference in the information that others provide for you.