Is it OK to only use the FW flush to winterize?

[Planetwarmer]

Is it OK to only use the fresh water flush on the transom to fill the engine with antifreeze? I sure would hate to crack the block. Any experience with this? The thermostat not installed. (454/Alpha 1)

[BlownCrewCab]

as long as you have Drained all the water out (by opening all valves and pulling off some hoses) it's okay to refill with anti-freeze from there. I wouldn't rely on it displacing all the water with anti-freeze just by running it through there. you need to start with an empty block.

[chrisc2]

Pwarm - You can do it that way providing you go with a premixed blend in a bucket of some sort. The baseline is 50/50% for protection to -34 D/F. Put the drive in a bucket with the antifreeze water mixture and start it up. Leave the water in the engine! Do not try to drain it beforehand. You can use a hydrometer or refractometer to measure the mix beforehand or mix up 4-5 gallons of -50 antifreeze with some water and call it good. How cold does it get where you live (worst case- and for how long)?

[chrisc2]

Also, warm up the engine on the hose beforehand (yes even though you do not have a thermostat). The close to -50 mix will dilute to approx -34 or better when run through the engine. There is more you can or may need to do after this depending on your local conditions and how the boat is stored.

[RedDog]

I have always just pulled all of the drain plugs and lower hoses - from sea-water pump, power steering/oilcooler, re-circ pump. The pour the anti freeze in from the top thru mainifold hoses until it runs out the tips or prop, steering/oilcooler, and thermostat housing - just fill it up. Of course you do this after it has been fogged.

This is for an OMC big block but essentially the same for any:

Winter Shutdown
• Grease gimbal
• Grease steering cable
• Change oil
• Change outdrive lube
• Add Sta-bil at the last outing
• Warm up and fog
• Drain fuel bowl
• Loosen belts (tighten in spring)
• Spray engine with CRC 656 (clean and re-spray in Spring)
• Drain manifolds (4 drains each), Block (drain each side), Oil cooler (2 drains)
• Remove drain screw on drive water pump. Blow out hoses with air.
• Remove large hose on engine water pump and drain.
• Put drain plugs back in
• Fill block and manifolds with antifreeze (Drain and save in spring for next season
• Need approximately 8 gallons antifreeze - use full strength
• Fill block through large hose at thermostat housing
• Oil and power steering cooler and seawater pump through sea water hose (the one with the copper adapter) antifreeze will run out of seawater pump (On back side of drive)
• Manifolds and risers through 2 small hoses connected to thermostat housing (antifreeze will run out of tail pipes)
• Store with the bow UP and the drive down.

[MOP]

Don't forget to supply water the the drive or pull it off so you don't burn out the pump.