Shurflo fresh water wash

Good morning, under the port seat at helm there is a storage area there with 2 draws , after taking draws out no access behind draws , but I can most likely remove that , storage box I’ll call it that draws slide on and maybe that is my access , I did not remove yet lost my daylight and other thing came up had to stop , didn’t want to rush it , thnks
 
I just purchased a 1998 Gulfstream and I was scratching my head trying to locate the fresh water holding tank. The poster is correct in that the fresh water pump is in fact located at the transom (most likely due to the fact that the cockpit shower is back there). I have read that the tank is located behind the storage drawers under the port helm seat. Everything was working on my system so all I did was disconnect one end off the pump and pump antifreeze through the system until I saw pink out of the sink and the cockpit shower. Hope this helps.
 
The fill for the fresh water tank is located under the port helm seat
 
I have the same Boat. I run the fresh water till it just spits. I put about 1 gal of RV antifreeze in the tank. Run the sink and shower till it runs the color of the antifreeze. You can then Take the hose unions on the pump off if you like. Here's a tip on the live bait well winterizing. There is a flow check in the stern after the sea cock. I remove it because it will hold the water in the line, I had one crack one year.
 
Just add anti-freeze to the tank to prevent freezing. Then, after you replace pump, you will be able to pump out tank, fill with a dash of bleach and water. That will clean out everything, pump it out and fill - good to go.
 
Dukke, you can drain the water out of the tank by using the hose in the bilge (where the other end is attached to the fresh water tank). Either siphon it out, use a little hand pump... or just connect it to one of your other pumps nearby. Then you can add some AF to the tank and pump again to make sure you get AF through the lines (in case of any dips/low spots). The tank, itself, once you pump it dry will be fine as any residual water won't be anywhere near enough to do any damage. But it can't hurt to put some AF in there, of course.