Gray water tank not emptying

[Bduck100]

Jayco 29w 2018, gray water tank does not empty because of a ballooning effect at the bottom of the tank which leaves about 4 gallons in the tank. The ballooning is below the drain Port for the tank hence incomplete draining. Has anyone had this problem and what are the fixes that have been used. Thanks,
BD

[wmurphy]

My 2019 29MVP is doing the same thing. They also plumbed the drain line so that it has about a 2" rise. It's going to the dealer tomorrow.

[RetiredOne]

Originally Posted by Bduck100

Jayco 29w 2018, gray water tank does not empty because of a ballooning effect at the bottom of the tank which leaves about 4 gallons in the tank. The ballooning is below the drain Port for the tank hence incomplete draining. Has anyone had this problem and what are the fixes that have been used. Thanks,
BD

Maybe a fix can be adding another support strap in the middle of the tank, and stick a block in between, to push up the center of the tank?

[Bduck100]

Thanks, I have deviseed a couple of plans but was hoping someone, smarter than me, had come up with a fix so I could avoid my usual trial and error.

[Bduck100]

Originally Posted by wmurphy

My 2019 29MVP is doing the same thing. They also plumbed the drain line so that it has about a 2" rise. It's going to the dealer tomorrow.

My warranty just expired so dealership is not an option. My experience with Jayco customer service and their recommendations has been great while I was under warranty. Hope you have the same experience.
BD

[gprapim]

Originally Posted by Bduck100

Jayco 29w 2018, gray water tank does not empty because of a ballooning effect at the bottom of the tank which leaves about 4 gallons in the tank. The ballooning is below the drain Port for the tank hence incomplete draining. Has anyone had this problem and what are the fixes that have been used. Thanks,

BD

Sometimes my 2017 29W will do this and I extend the passenger side levelers to tip the unit and then it will drain completely. The problem seems to be that the dump valve outlet is almost at the same level as the bottom of the tank and it cannot be lowered anymore due to ground clearance. If I drain it on level ground, it will leave the tank with a reading of 1/3 full until I lower the levelers as stated.

[Bduck100]

What a great suggestion! Easy enough to raise one side with the levelers. I will do this until I get a permanent fix.

[gprapim]

Originally Posted by Bduck100

What a great suggestion! Easy enough to raise one side with the levelers. I will do this until I get a permanent fix.

Thank you.
If you do come up with a permanent fix, please get back to us with your answer to correcting this situation.

[Armyman97]

Mine had basicly the same issue, looked at the outlet of grey tank and outlet of dump valve, which was 1-2 inches higher. The dealer lowered the valve by extending black tanks drain line to lower dump valve. Prior to this I used the same trick with the leveling jacks. 2018 29MV.

[Bduck100]

My Fix: 2 1x10 3 ft long boards screwed together and placed at an angle under the support straps. Took about 20 mins. As mentioned in other notes my drain valve is a little higher than the drain Port at the tank but not so much that this fix doesn't work. There was 5gal left in the tank before the fix now maybe a quart. I can live with this.

[gprapim]

Originally Posted by Bduck100

My Fix: 2 1x10 3 ft long boards screwed together and placed at an angle under the support straps. Took about 20 mins. As mentioned in other notes my drain valve is a little higher than the drain Port at the tank but not so much that this fix doesn't work. There was 5gal left in the tank before the fix now maybe a quart. I can live with this.

Can you send a pic or two of the job you did. Sounds good. Maybe it will correct mine also.

[Jim Davis]

With my Hummingbird I have to raise the tongue jack almost to fuse blowing. I retract the rear stabilizers then raise the front till it drains. When dine re-level and stabilize.

[Bduck100]

Here are the photos. I used 4, 1 and a 1/4 in screws to secure the boards to each other. Two at each end. I used one screw through each strap so the boards would not move. Spray painted to help prevent water absorption. I emptied the tank before starting just to make it easier to push up and get the board under the straps. Also placed the boards under the straps before I screwed them together. Note also that I angled the boards to give the best lift.
BD

[gprapim]

Originally Posted by Bduck100

Here are the photos. I used 4, 1 and a 1/4 in screws to secure the boards to each other. Two at each end. I used one screw through each strap so the boards would not move. Spray painted to help prevent water absorption. I emptied the tank before starting just to make it easier to push up and get the board under the straps. Also placed the boards under the straps before I screwed them together. Note also that I angled the boards to give the best lift.

BD

Thanks for the pictures. And that solved your dilemma and now get a full tank drain?

[Bduck100]

I just checked and there is about a quart left
This is most likely from the drain line being higher than it should be. There's a strap holding it by the valves which I plan to adjust so it will lower the valves about an inch. That should be enough to get the tank completely empty. Before the modification there was exactly 5 gallons left in the tank.
BD

[gprapim]

Originally Posted by Bduck100

I just checked and there is about a quart left
This is most likely from the drain line being higher than it should be. There's a strap holding it by the valves which I plan to adjust so it will lower the valves about an inch. That should be enough to get the tank completely empty. Before the modification there was exactly 5 gallons left in the tank.
BD

Be careful lowering the drain valve outlet. Ground clearance is at best at a minimum, as it is. I primarily boondock and I have broken it away once, dumping both tanks unknowingly and having to repair it before going any further, and have ground it down on other occasions. I was fortunate that I planned ahead and had the needed parts (the “y” connector) to fix it on the spot (I knew that someday I was going to break it off, since it hangs down so far). And I don’t go into places where I shouldn’t be able to go. Heck, I have scraped it coming out of a restaurant that had a pretty good incline just before the street. Just sayin’.

[Bduck100]

Thanks for the caution. Every bit of ground clearance is needed. We are full time and also boondock a lot. So far I have not hit the plumbing but did scrape one of the jacks once. I can live with the tank and drainage as it is so probably will.
I believe I gained a small amount of ground clearance be adjusting the helwig helper springs.

[gprapim]

Originally Posted by Bduck100

Thanks for the caution. Every bit of ground clearance is needed. We are full time and also boondock a lot. So far I have not hit the plumbing but did scrape one of the jacks once. I can live with the tank and drainage as it is so probably will.
I believe I gained a small amount of ground clearance be adjusting the helwig helper springs.

I also adjusted my helpers to 2”.
Afterwards, I didn’t noticed any difference in the ride and there might be a little more ground clearance, but if so, not very much. Mine were at 4” from the factory and were doing absolutely nothing for me. At least now having them set, they can work for me when they are needed. Whereas before I adjusted them, they were there with nothing to do but add weight. Good luck with your coach and safe travels. Happy Trails !!

[Trapper2020]

Thanks for the pictures my 29mv has the same issue. I will be adding this fix. One question did you have to loosen the support straps or were you able to get the boards in by force?

Enjoy the journey

[Bill Johnson]

Jayco should have built it right in the first place