Re: A/C ON 1997 33FT FORMULA(AIR CONDITIONING)
If the intake valve is shut, then you may not have to but should anyhow. If it is open, you do for sure. There'll be a fitting under the hull where cooling water enters. You basically force antifreeze in there until it forces the water out and antifreeze comes out the drain fitting, usually just above the waterline. Even if that intake valve is off, water will enter where it exits.