"Recently while motoring my 41’ yacht in a fairly heavy sea the engine cut out as if it was starving for fuel. After sailing back to port, and then some inspection/diagnosis I found that the fuel line from the tank to the primary filter/separator was blocked. I attempted inspecting the fuel tank but the only opening was for the fuel sender which gave a very limited view of the tank contents. In an attempt to get a better view I emptied the tank (150 liters) and found there was significant amounts of diesel bug sludge on the bottom of the tank and on the walls of the tank. It was the sludge which had accumulated in the fuel pickup/hose and cut fuel supply to the engine. Realizing I needed permanent ongoing access to the tank for cleaning and inspection I searched online for some sort of port for the fuel tank. I quickly found the Clean Diesel website and ordered two tank access ports. Receiving and then inspecting the ports they were clearly an excellent quality product with all required gaskets and fasteners. Fitting them was very easy using a drill, multi-tool with a bi-metal blade, a half round file and a hole de-burring tool. After creating the openings for the ports I was able to clean the tank by using a paint scraper, scrubbing brush and paper towels. Once the tank was relatively clean I used paper towels and Isopropyl Alcohol to get it to an immaculately clean state. I replaced the main fuel line and both engine filters and the engine is now running perfectly. I can absolutely recommend this solution from Clean Diesel. After my engine failure experience if I were to purchase another boat, sail or power, the first thing I would do is check it had tank access and if it did not I would fit Clean Diesel Tanks access ports."