The year 1999, when I was building the diesel fuel polishing system for our boat, a Teflon joint compound from Permatex for NPT pipe joints was the hottest ticket on the market, apparently good for everything including water and gasoline or diesel fuel. It was so easy to use, a real blessing for a pipe fitter. I used it too. It speeded up the job so nicely on the two diesel filter panels I was building for our Diesel Duck under construction back then. When we launched the Duck in May of 2005 and I pumped for the first time diesel fuel through these panels it all looked so good and that it gave me a happy feeling. Two years later, in 2007, when the first pipe joint started to weep diesel fuel, my happy feeling was getting a punch. From that time on the happy feeling received countless punches as every pipe joint started to weep and leaking and it almost turned into a flood of diesel fuel. It needed some serious fixing done.



Here in Annapolis, having access to all kinds of stuff from finest bread to good wine and all the tools a man can dream of at the building centers like "Lowe's" or "Home Depot" I was thinking of using the idle times of the few months weathering out the hurricane season here on a mooring on Weems Creek to fix this problem. I learned quickly the cure would be unscrewing every pipe joint, cleaning the thread and using yellow Teflon tape, also called yellow gas line PTFE tape to seal the joint. Hunting down this tape became a challenge. Sure, I could buy a tape at the Home Depot, but it was a no name product not showing a ULC approval number or CSA number. It was some cheap China tape. I had enough problems and did not need a future new pain in the ass. I found the real Made in USA yellow Teflon tape with all the approval numbers for professionals at "Fastenal Company" here in town.




Diesel Duck's galley became a workshop for a short time. I drained all the diesel out of these filter panels and removed the panels one at a time for the rebuild job. We salvaged the diesel, a good 2-1/2 gallons and Marlene cleaned the fuel while running the diesel through a coffee filter. It was black diesel, but it came out clean like a whistle. For cleaning the male pipe thread I gently used the wire brush wheel on an electric 6" wheel grinder. To clean the female thread I used the proper ½ inch NPT tap, in another case it was a ¼ inch NPT tap. I applied the minimum 3 wraps required for the yellow gas line PTFE tape (Teflon tape) on the male pipe threads and assembled everything.




After installing new filter cartridges, the panel got primed with the cleaned, recycled diesel fuel and put back in service. Time will tell and I keep my fingers crossed and hope the pipe joints will stay dry from now on!!