Black Tank Flush

[Apprenticelinem]

So, I flushed my black tank, but forgot to leave the valve open. It didn't flush very long, but I did get a scare. The camper made 2 loud noises and bounced a little like someone ran into me. I ran outside to see what was up, then remembered I left the flush going. I pulled the valve open and let it all drain out while killing the water feed. I don't see any signs of damage (no leaking water under or inside the camper) but I'm not sure there's no real damage. How will I know for sure?

[Apprenticelinem]

I looked at the suspension, everything seems in place. Had the camper for less than 3 months so far and it's been parked at the same campground. I figured the rapid onset of weight and no place for it to go is what made those noises, but wasn't sure, hence my asking on this forum

[Bipeflier]

It is possible the weight of the water caused the trailer suspension to shift or settle. Have you checked the suspension components for wear lately?

[Executive45]

Just be happy you didn't flush the toilet while that pressure was built up...:B:B....Dennis

[Lynnmor]

dodge guy wrote:
Probably built up an air pocket that ended up venting through the vent once the pressure built up enough..

The vent pipe can fall to the bottom of the tank and cause what you are saying, otherwise there will be no pressure.

[dodge_guy]

Probably built up an air pocket that ended up venting through the vent once the pressure built up enough. If you see no leaks and everything is operating properly I think your fine.

[ChuckSteed]

I don’t use the built in black tank flush. Too many potential problems. A Flush King adapter with clear section and external gate valve lets you see when tanknis clean and prievents surprises when taking off sewer cap.

[jplante4]

Most likely the vent is plugged with animal stuff (nests etc) and the pop was the tank expanding and possibly relieving the pressure. Now, if it relieved the pressure by pushing out whatever is in the vent stack, you're lucky. Stick a hose down the pipe and make sure it doesn't back up to the roof.

If you're unlucky, the top of the tank cracked and you have a big job in front of you. Fill the tank and look for leaks.

[Lynnmor]

Since the tank is vented thru the roof there should be no pressure to cause loud noises. I think you should investigate where the noise came from by removing any bottom cover and checking the mounting of the tank. While it is open, completely fill the tank and listen for noise and watch for leaks. Check the vent for proper ventilation.