Call Marina Yucalpeten on channel 74 VHF as you approach the harbor for help from the dock master. Marina Office hours are from 8 to 4 . Water, power, 24 hour security, Fuel Dock, ice and Coke products and Beer.
http://www.yucatancruising.com/Yucatan_Cruising_Guide/Marinas_Yuckal.html