Eliminating the 2nd sewer dump outlet, Done!

[SargeW]

After asking some questions here on the site, and getting some great input from the likes of JRTJH (John) and rhagfo (Russ) I decided to replumb my 2nd gray tank to dump into the main sewer outlet at the rear of the TT.

The first issue was deciding where to cut the existing dump outlet to allow the addition of the new 3X3X1 1/2" Wye for the front tank to dump into. So the first decision was was how to position the Wye in such a way that the new 1 1/2" line could get past the existing gray tank dump handle. The only possibility was to cut back the existing 3" dump line as far back as I could so that the new 1 1/2" line would fit right under the handle. This would allow the new line to slope downwards at the end to encourage a steady flow of water to the low point. Cutting the existing pipe was done with a reciprocating saw with an abrasive blade. Cutting upwards with the saw was slow as I didn't want to cut into any of the wire bundle that was laying on top of the coroplast liner.

With the existing line cut I could position the new Wye to accept the new line from the front. The new line had to run tight to the bottom of the frame to clear the mounting brace for the electric stabilizer jacks. The new line slid rigth over the top of the mounting brace. A 45 degree sweep at the Wye lined up the new line perfectly. Then 12' back to the secondary gray tank was fairly easy, and to make the connection at that tank I cut the existing 1 1/2" line and dump connection as close as I could to the bottom frame of the TT and still fit a 90 degree sweep on the end. With the sweep positioned close to the bottom of the TT frame keeping the new pipe tight against the TT coroplast was easy. I opted to glue the all the joints from the main sewer dump backwards until hooking up to the 90 degree sweep from the front tank.

I opted to use a mechanical connector for ease of install, and to allow any adjustments later if necessary. Pipe supports were sourced from HD as well as the rest of the needed parts. All together the cost of the mod was $80.

All I have left to do is to reapply some spray foam I took out to visually look around the pipes I cut to avoid any obstructions (like wires which there were plenty).

I test the system by running water in the sink for about 5 minutes with the dump valve closed, then pulled the handle with the main dump cap off. I got a steady stream of water until the tank emptied.

So far so good, and I will get to test it in real time next week.

[rhagfo]

Very nice!

[Ron B]

Nice job! I'm still deciding if I want to do this on my 29RKS. I'm a little nervous cutting into the line but I will probably do it when it gets warmer. Dumping the kitchen has always been a pain.

[Camping family]

Originally Posted by Ron B

Nice job! I'm still deciding if I want to do this on my 29RKS. I'm a little nervous cutting into the line but I will probably do it when it gets warmer. Dumping the kitchen has always been a pain.

If you decide to do it. Please let me know I have the same camper and would also like to do that.

[rhagfo]

Originally Posted by Camping family

If you decide to do it. Please let me know I have the same camper and would also like to do that.

Just do it! If mine had come with separate connection for the galley tank, I would have done it asap.

[SargeW]

I got to try the new connections out this weekend. The site we were in had a pretty good slope from back to front, so the back main sewer dump line was within about 12" from the dirt. But I still had plenty of room to hook the single sewer hose and use a support to keep it off the ground. Dumping went well, I pulled the front valve first, which is the new modified line. I had good flow but not much volume as the kitchen sink wasn't used much on this trip.

Normally I will leave the gray tank open with a "P" trap in the dump hose to keep out sewer fumes, then close them the day before we leave to build up some water to flush the lines.

The mod is working well, and I would support doing the mod if you have a double sewer dump situation. Just be sure to do a dry run with your pipes first to insure you will have the necessary room for the new pipe and fittings. The 1- 1/2" ABS is pretty easy to work with though. For fast, straight cuts I used a power miter saw with a carbide tipped saw blade. Cut clean with no burrs.

[travelin texans]

If it's only the galley or bath grey tank that's seperate rather than replumb the lines I'd use the cap pictured & just connect a dedicated water hose to drain that tank, it should just be liquid.

[rhagfo]

Originally Posted by travelin texans

If it's only the galley or bath grey tank that's seperate rather than replumb the lines I'd use the cap pictured & just connect a dedicated water hose to drain that tank, it should just be liquid.
Attachment 43259

I would say it is all about convenience, still a second hose to drop in the drain. we keep our galley drain open all the time, and use the forward grey tank closed to use to flush after dumping the black tank.

[SargeW]

Yep, I am all about convenience. After full timing most of 15 years I have hooked and unhooked a million sewer hoses. Only needing one hose instead of two was well worth the $80 and a few hours.

[Kirk's Keystone Outback.]

Originally Posted by SargeW

Yep, I am all about convenience. After full timing most of 15 years I have hooked and unhooked a million sewer hoses. Only needing one hose instead of two was well worth the $80 and a few hours.

Your reason for the mod makes sense. I've made mods to my TT, generally for my convenience. Usually I'll identify that something could be better, and then I'll dwell on it for a while to justify and plan the actual mod. I've been very happy thus far in this process, and the mod you posted would be something I'd consider down the road. Thanks for sharing the results.

[dutchmensport]

Looks real good, nice job.

[CBears]

Older post I know but you did a great job. Thank you for posting!

[SargeW]

Thanks for the comment!

[cougar23]

Originally Posted by travelin texans

If it's only the galley or bath grey tank that's seperate rather than replumb the lines I'd use the cap pictured & just connect a dedicated water hose to drain that tank, it should just be liquid.
Attachment 43259

This is what I use on my 2nd gray tank. I also use a dedicated garden hose which I either run to the dump hole or onto the ground if permitted.

[Flip]

Man, you got it figured out. Where did I put that hacksaw?