Gray Drain

[Aidan Trainor]

Hi , I'm new to the Oliver scene. We had a 5th wheel and are getting use to the Oliver Elite 11 . I have one question ,  why does the gray tank drain very slowly. The black tank drains quickly. Has anyone had or have the same issue? 

Thanks Aidan 1455

[Townesw]

Hello Aidan.  The gray tank will drain quicker if the front of the trailer is raised a little. Raising the curb side a little near the end of the process also helps. The gray tank is long, narrow, and thin and the drain valve is on the left side rear corner of the tank. 
 

 

The gray tank level sensor on hull 313 is located where the yellow blotch is shown on the picture below. My tank level could show 0% and still have water in the rear of the tank if the nose is too high. 

 

 

Bill

Edited 3 hours ago by Townesw

[Aidan Trainor]

I did raise the front put it still seams to take a long time to drain , not of water flow. Im used to a large flow when I pull the handle , very very slow stream.

[Townesw]

My gray tank was draining really slow one time. I filled it then drove around and went home and backed it down a slope and dumped. The water came out with force and brought out a nasty looking slime. Since then we have added dawn dish washing soap and traveled with some water in the gray tank. I try to dump the gray soon after getting home while backed down a slope so as to get really good flow. It still drains slow due to the size and layout of the tank but it was much better after I got the algae (?) out of it. 

[Townesw]

Look under street side bunk. Make sure valve is open all of the way when handle is pulled. Also if you’re going to fill it lay a water hose in the shower pan (but watch it REAL close) and really raise the nose so you are washing the bottom of the tank. Fill tank until water stops draining in shower pan. Be sure to quickly turn water off. Open the valve and let it rush out. Do it a few times. Watch what comes out if you can. You know that white snot that grows in HVAC condensate pans and lines? I think similar stuff grows in gray tanks. I think #1455 has sat unused and you have a build up in your tank. 
 

I think people set these trailers up level, hook up to the sewer and open the drain and let the water out as it is filled. This lets solids settle on the tank floors. We were told to keep the drains closed and only dump when the tanks were filled so that solids could be flushed out. We always  dump black first. Then we use the flush inlet and fill and drain the black tank 3,4,5 times until I don’t see anymore floaters (we don’t put paper in our black tank) in the clear elbow at the sewer connection. Then I open the gray tank and let it drain while I do something else. After a few minutes the gray tank level is 0. Since I got that gunk out of my gray tank I haven’t had any problems. It will still drain slow but I eventually get to 0%.

Edited 2 hours ago by Townesw

[jd1923]

20 minutes ago, Townesw said:

I think people set these trailers up level, hook up to the sewer and open the drain and let the water out as it is filled. This lets solids settle on the tank floors. We were told to keep the drains closed and only dump when the tanks were filled so that solids could be flushed out. We always dump black first. Then we use the flush inlet and fill and drain the black tank 3,4,5 times until I don’t see any more floaters (we don’t put paper in our black tank).

Bill has provided a lot of good advice here!

Agreed, the worst thing you can do is the campground slow drain-as-using routine. Always drain tanks as near full as possible. And it's better to dump after towing, for a cleaning action to break down the solids. Thinking in this way, we often dump when we arrive at a campsite vs. as we're leaving (no long lines at the dump station either).

Our Black Tank mostly empties in about 20 seconds and the Grey in a minute or two max. We always camp with the nose up about 3/4" on the LevelMatePRO to help out the water pump. We always dump tanks with the nose up 2-3" and the curbside leveler up 1-2". If you fail to raise the curbside, you can think the grey is empty and it's still partially full (see Bill's picture above).

IMHO SeeLevel readings are next to useless. They say these are more accurate than other brands, but they all show bad readings. We've learned from experience how many days the fresh tank will last (depending on showers taken), and when the Black and Grey waste tanks will fill (for battery SOC get a shunt with Bluetooth). Think about your usage and learn. I stopped looking at our SeeLevel display long ago.

We put some TP in our Oliver toilet which does not cause an issue when draining tanks properly. Of course, you don't want TP nor solids sitting on the bottom of an empty tank, so always add at least 1 gallon of fresh water prior to toilet use and have the bowl half-full when using.

We used to add cleaners but stopped doing that except for an occasional cleaning as-needed. If ours were ever to drain slowly at the dump station, after dumping I would refill both waste tanks about 3/4 full, add some low-suds laundry detergent in both tanks. Then tow onto our next destination to use the road for cleaning action, dump on arrival at the next campsite.

To fill the black or grey 3/4 full, I use a gallon counter on the hose. The black tank has a hose connection, and I put the hose right down the kitchen sink drain to fill the grey. After cleaning, refill both tanks and drain again until the water looks clear. If you do not have one already, your drain hose should have a clear section or elbow where you can see the liquids while draining. In storage have a couple gallons of water in all 3 tanks (don't worry, nothing bad will happen if a tank 10% full freezes).

[Aidan Trainor]

Thanks for all the info.