Thread Tools Display Modes
Old 09-27-2017, 10:25 AM   #1
Junior Member
Join Date: Jun 2010
Posts: 3
Black Tank Flush Leak on 2010 355QBQ Check Valve

Check Valve Location - I have two black tanks in a 2010 Sierra 355QBQ - tank 1 rinse caused water to be noticed on floor next to master bedroom steps. After getting home I made calls to FR, and to the service dept where I purchased - niether knew where the valves were - was hoping would be under sink as previously posted, but no luck. After taking out panels in pass through bay, slicing a peep hole in my underbelly, taking my shower faucet handles off I was stumped. I decided to check behind my entertainment center in my living area (knowing the valves have to be installed higher than toilet) - there was a hole in wall about size of fist for wires to come into the back of the entertainment center. I put my hand down inside the hole and felt what seemed like pex and valves (yes two). I hooked up waterhose to flush 1 and let her rip - sure enough water started coming out - not dripping but a forceful stream. With no hole, I took off a cabinet door beneath entertainment center and removed panel holding an electrical plug - I then cut a square hole in paneling and replaced valves and then screwed a piece of paneling that I can get to in the future.
BamaAF is offline   Reply With Quote
Old 09-27-2017, 10:29 AM   #2
Fulltime family RVer
ependydad's Avatar
Join Date: Nov 2011
Posts: 19,906
Thanks for sharing. Iíve looked for my valve on my Sabre and canít find it. Iíll check in the same ballpark area.
2018 Ram 3500 DRW/crew cab/long bed/4x4/4.10 gears pulling a 2017 Spartan 1245 by Prime Time
Checkout my site for RVing tips, tricks, and info | My family and I have fulltimed since June 2015
ependydad is offline   Reply With Quote
Old 09-27-2017, 01:27 PM   #3
Junior Member
Join Date: Jun 2010
Posts: 3
No Problem (more)

After more thought I bypassed the valves - I will just remember to dump/flush at 3/4 instead of full - not sure it would matter, but just in case, I will dump prior to tank reaching the flush jets - and I will use a flow back prevention on outside of trailer when flushing. What I did was got a 90 degree elbow that was a half inch slip on one end and a half inch thread on the other end - a strait converter that was half inch slip on one end and half inch thread on other end ---- then I cut one and a half inches of 2 inch pvc and glued all together -- this gave me the angle/direction I needed to screw the home made bypass pvc into the existing pex (where I removed the port) -- I had to do twice since I have two tanks. If this causes any issues as far as draining or whatever I will put the valves back in-line. This will hopefully prevent future malfunctions and leaks inside my wall.
BamaAF is offline   Reply With Quote

black, black tank, black tank flush, check, flush, leak, tank, valve

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

» Featured Campgrounds

Reviews provided by


This website is not affiliated with or endorsed by Forest River, Inc. or any of its affiliates. This is an independent, unofficial site.

All times are GMT -5. The time now is 03:12 AM.