07-13-2021, 02:19 PM
on my 1998 express 3500, the vacuum tank and pump is located under the stairs when you enter the cabin, you open the stairs and take everything out, there is a door / cover there so if you remove it you will find it. The holding tank on my boat is under the lounge seat right below the breaker panel you remove the seat cushions, open the latch and remove the door/cover on the bottom.


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