2003 Safari Trek black tank flush?

[rv2go]

My neighbor has a new to him 2003 Safari Trek and needs help flushing his black tank. There is a hose connection marked "Black Tank Flush". The problem is when the hose is attached and water turned on, water does not flow into the tank. We can only trace the plumbing for a few feet before it goes behind a compartment wall. Could there be a shut off valve someplace that we have overlooked?

Any ideas or suggestions?

[zekegb]

Suggest posing question on Trek Tracks website. Very informative forum for Safari Trek owners. Lots of info.

[rv2go]

Thanks for the replies here and for the PM's. Hopefully with the info given, he can get his black tank flusher working.

[rgatijnet1]

If all else fails, try filling the black tank and letting it sit and soften up any dried debris that may be clogging the flush line.

[RudysWorld]

On our Georgetown there is a back flow valve may want to check if has or if is bad. Also, my black tank flush will only work with black tank empty handle in the open position.

[raymondfl]

On top of the black water tank is a spray valve, you have to take that valve off and clean it, it is more than likely clogged up. By taking the valve off and cleaning it out you should be able to have free flow of water. I do not believe there is a check valve or back flow valve therefore I believe your best option is the spray valve.
Good Luck

[road_glide]

We just used our black tank flush yesterday. It didn't seem like water was going in or coming out, but we shut it off and checked the sewer hose and indicator light and it read empty...I've seen pictures of where the hose goes into the black tank. It is the same size as the rest of the water lines. So try opening the faucet part way? Read the indicator level light also when done. Our Safari manual said run for 2-3 minutes.