Easiest way to check for grey tank blockage?

[RV 4 2]

I think I have a floatie in my grey tank. (yea, I know, that is a personal problem )but I get inconsistent results when draining my grey tank. Sometimes my grey tank will flow like crazy and other tiems it just trickles. Most of the time it starts with good flow but then close to what I think may be the end, the flow will go to a trickle. I will go check my levels and sometimes it still registers 1/3 tank. I know the sensor will go to empty because if I let it drain for 5-10 min more, the sensor will show empty but it still trickles.
I have heard of people who find that when one of the holes was punched in the grey tank, that piece of plastic was left in there.
SO, does anyone have any good ideas as to how I can see if that is my problem without any major surgery on the tank?
Thanks

[RV 4 2]

I think I have a floatie in my grey tank. (yea, I know, that is a personal problem )but I get inconsistent results when draining my grey tank. Sometimes my grey tank will flow like crazy and other tiems it just trickles. Most of the time it starts with good flow but then close to what I think may be the end, the flow will go to a trickle. I will go check my levels and sometimes it still registers 1/3 tank. I know the sensor will go to empty because if I let it drain for 5-10 min more, the sensor will show empty but it still trickles.
I have heard of people who find that when one of the holes was punched in the grey tank, that piece of plastic was left in there.
SO, does anyone have any good ideas as to how I can see if that is my problem without any major surgery on the tank?
Thanks

[ET]

If you believe it's a piece of plastic covering the drain hole leading out of the tank and it shows 1/3 tank try using a plumbing snake up from the valve into the tank and see if the flow goes back to solid instead of trickle. I'll assume you'll do this with a grey tank of clear water of course. If it does then at least you'll know the cause for sure. Good luck

[speed racer]

You could use a plumbers scope and run it back up the drain into the tank. I have an 05 dolphin and it drains the same way and I have heard from other owners with the same problem. I beleive the shape of the tank is what causes it to drain the last 1/3 real slow. The tank is a very large thin tank and after it gets down a little there is no force behind the water because it is only a couple of inches deep. I raise my right front jack and it seams to help.

[Rick 2005 Dolphin 5376]

You can raise the front right and left independently? I can only do that with the rears, darn.

[RV 4 2]

Thanks for the hints. I will have to figure something out. I might have to do that clear water idea.

Now to find time to do it. ...

[two2go]

Mine is slow, too. Let us know if you find anything. I ain't motivated to go lookin' right now.

[ET]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by RV 4 2:
Thanks for the hints. I will have to figure something out. I might have to do that clear water idea.

Now to find time to do it. ... </div></BLOCKQUOTE>

Good luck in your search for the culprit causing the problem and remember...
It could have been the black water tank!

[RV 4 2]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by ET:
Good luck in your search for the culprit causing the problem and remember...
It could have been the black water tank! </div></BLOCKQUOTE>

Amen to that. Thankfully that one flows just fine.

[CARVAL Motorsports]

OK, so twice now, after a 3 day weekend of trackside camping, we roll over to the dumpsite, pull the black tank valve, wait for the gush, wait for the gush... wait for the gush, NOTHING! I cannot believe that we have not generated enough mass to flow. The last time, we drove home, and went to a nearby State Park and dumped, and it flowed out. This time, it is out in the driveway, waiting for a decision. I figure I am going to fill it up with water, possibly this GEO Mixture, and try again.
Is this common to the 97 Dolphin. This unit is relatively new to us, but I was a Class C user for the past 12 years. Any suggestions. BTW, my grey water tank drains very slow at the end of the dump as well.

[RV Wizard]

CARVAL Motorsports, welcome to iRV2.com. We are glad to have you join us here and we look forward to reading of your adventures and experiences. Sorry to hear of the dumping problems. Since you are a veteran RVer, I would think that you may have a piece of the tank left behind from the pipe installation and will need to be removed. There is a company (franchizes) that have a camera and a pressure cleaning business that may be of help. I used them at a dealership in Arizona a few times. Got a dimond ring out of an Airstream with out having to pull the tank! Good luck and keep us posted on what you find out.

[Frankie]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by CARVAL Motorsports:
OK, so twice now, after a 3 day weekend of trackside camping, we roll over to the dumpsite, pull the black tank valve, wait for the gush, wait for the gush... wait for the gush, NOTHING! I cannot believe that we have not generated enough mass to flow. The last time, we drove home, and went to a nearby State Park and dumped, and it flowed out. This time, it is out in the driveway, waiting for a decision. I figure I am going to fill it up with water, possibly this GEO Mixture, and try again.
Is this common to the 97 Dolphin. This unit is relatively new to us, but I was a Class C user for the past 12 years. Any suggestions. BTW, my grey water tank drains very slow at the end of the dump as well. </div></BLOCKQUOTE>

Welcome to the site. Sounds like a good tank cleaning is in order.Grey tank sounds like buildup of sludge.Black tank sounds like blockage. You could try cleaning wand with the valve open,just make sure you have control of hose water flow.

[tropical36]

Mine was that way or worse when I got it. I put a small mirror in the 3" outlet and angled it enough for a looksee. It appeared to have a grease wafer at the valve opening. I managed to run a small water hose in the grey tank a ways and applied full water pressure for awhile, then pulling out the hose until it drained, then repeatedly done it again. It's been ok for about a year now. You also might want to drag your garden hose up top and shove it down the vent a ways, then turn it on for awhile to see what happens. I still don't understand why the didn't install a hose bib on mine like they did the black tank...2" drains instead of 1 1/2 would also be benifical, I think.

[CARVAL Motorsports]

We had a quick Labor Day weekend getaway to a Northern Ohio State Park on Lake Erie. After a long wait in line at the dump site (everyone exiting the park at same time), my turn comes up and I am holding my breath that things work correctly. With less than 1/3 in the black tank, it flowed out completely. This happened after I used the Calgon/Detergent mixture in the last dump ("Sitting in the driveway waiting for a decision")where I also filled the tank to almost max with water too. It flowed out then and this time as well, so I will continue "cleaning" the tanks with this GEO mixture. However, while dumping this afternoon, I still had the grey water tank wrap up ever so slowly... I finally stopped the flow because I did not want to aggrivate the remaining people in line. So, I will keep you posted on this matter. I am wondering if this may not lead back to a venting issue?
One thing I wanted to ask. Somewhere in these forums I thought I read that the Flush Valve that is installed on the black tank on my 97 Dolphin (and other models), may have been put in backwards or something like that. I hook mine up, turn water on to flush, and really, it is like back pressure, water starts to escape at the hose seals on both ends! Some water made it through because it would trickle out the hose... What gives on this??? Should I take this apart and check it out?
Besides this, so far, our well taken care of 97 NRV "535" Dolphin has been a pure pleasure. Enjoy it more each time out.
Sorry for the long post.

Carl of CARVAL