While checking my rig prior to dewinterizing, I noticed the black tank flush that is attached the side of the black tank had been leaking. This device is also known as a blank tank rinser. It allows you to connect a hose to an outlet outside the RV and shoot a stream of water inside the black tank to aid in cleaning. Most rigs today come with the add on upgrade.
I removed the three screws holding the nozzle to the black tank and could see the sealant they used did not adhere to the nozzle or tank. Black and grey tanks are notorious for sealants not sticking well to them. I removed and cleaned all the old sealant from the area
I needed to sand the black tank with 220 grit sandpaper to get a totally clean surface. I then cleaned it several times with isopropyl alcohol to give the sealant the best chance of adhesion. The video below shows the repair.
I used 100% Silicone Sealant for the repair. I applied the sealant then reinstalled the three screws to attach the nozzle to the tank. I allowed it to cure for 48 hours before testing. Black Tank Rinsers are a great way to help keep your black tank clean.
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