Black tank will not empty

john44004 · 07-10-2017, 06:21 AM

Hello all. Im kinda new here and have a Sunline 2363. I cannot get my black tank to empty. seems like this should be a pretty straight-forward job. Any ideas on possible issues. the idea of opening the valve and sticking a wire up thru does not seem like a good one. lol

mainah · 07-10-2017, 07:54 AM

Plenty of water in the tank?

john44004 · 07-10-2017, 08:19 AM

it almost full to toilet. lots of water

johnnybgood · 07-10-2017, 09:57 AM

Might want to try opening the dump valve with the flush valve in the toilet open. If it flows like that you have a clogged black tank vent.

mainah · 07-10-2017, 11:20 AM

A 3" pipe is real hard to block you are sure you are opening the right valve? They is a possibility the rod is moving and the gate is not.

john44004 · 07-10-2017, 11:54 AM

I only see 2 valves. when I pull the first one the grey tank drains. when I pull the other nothing but maybe a little dribble. it is possible the gate is not moving but how do I check with a full tank?

mainah · 07-10-2017, 03:38 PM

Therein lays the problem. I don't think any one will tell you this would be a pleasant task the only thing I can think of is a big concave dump site and hope for the best broom stick might be in order. If this is a new to you camper you have no ideal of what went in the toilet a disposable diaper comes to mind or even a plastic bag.

**Sunline Fan** · 07-10-2017, 03:52 PM

I would try Johnny's suggestion first. If that doesn't work, is the trailer set up on a seasonal site or no? I'd tow it around the block and see if a little bouncing will help dislodge things. Valve closed of course.

If the rod is coming all the way out on the valve, it should be opening all the way. It doesn't feel like different pressure at various points as you pull the valve open, does it? Such as hard at first then easy?

**JohnB** · 07-12-2017, 08:40 PM

If you crawl under and look at the valve stem on the end of the black tank dump valve, and that valve stem moves 2" to 3" or some part of that, then the slider valve should have opened.

If that is the case and no water is coming out, this sounds like a clogged tank discharge port.

Is your dump valve straight up from the end of the 3" dump connection or is there a 90 degree elbow there? Straight up makes this easier to unclog.

See this post it may help http://www.sunlineclub.com/forums/f7...tml#post135863

They show how to make a blaster tube you go in with to break up the clog. You may need to go up the dump pipe with the blaster tube. Since the tube is like 1/2" OD or so, hopefully it will not all break loose at once to allow you to get out of the way when it does break loose.

Good luck and let us know how this goes.

John

**JohnB** · 07-13-2017, 08:18 AM

Also see this post from Trailblazer on unplugging a clogged tank from the dump pipe. They show how to not make such a mess.

http://www.sunlineclub.com/forums/f7...tml#post138205

Hope this helps

John