Converting dump valves

[Flynavy]

Our 75 is a twin bed rear 3/4 bath model. I pulled the above floor black tank in order to replace a section of rotted floor. Since it's all apart I thougth it would be a good time to repair the Thetford dump valves being as neither of them close.

When I couldn't get them apart I decided to just take them out completely and replace them. I had to cut the 3" ABS since the Thetford valve was glued at the black tank pipe end. The gray tank valve was the press on type so it came right out.

Being as it's all apart now I'm wondering if it would be best to just put in Valtera valves now and do it in a way where it could be serviced a lot easier next time around.

Has anyone done this? Any input would be helpful.

Thanks, Paul.

[Aage]

Have a look at the results of this search. One of them is directly on your question.

Good luck with your mission!

[sandlapper]

Don't know what is best, but the Thetford valve is rebuildable. A kit is available from Out OF Doors Mart. The valve itself seperates via 6 or so screws so you can replace the gaskets & the blade. I bought an entire new valve, used the parts I needed since I did not remove the entire valve to work on it.

[Flynavy]

Thanks for the help. Looks like Valtera is more common, Thetford a little better made. Main thing I need to work out is a setup where I'm not forced into cutting pipe or pulling tanks to get the old ones out. Maybe a frunco here or there would do the trick.

[RickDavis]

The Valterra valves are available anywhere and reasonably priced. The Thetford is pricy and uses adapters that are pretty well non standard these days. Both should be rebuildable.

I would change to Valterra

[Phrunes]

Originally Posted by Flynavy

Thanks for the help. Looks like Valtera is more common, Thetford a little better made. Main thing I need to work out is a setup where I'm not forced into cutting pipe or pulling tanks to get the old ones out. Maybe a frunco here or there would do the trick.

I just redid my entire dump system, including conversion to Valterra. I, like you was looking for a way to disassemble easily at a later date without cutting black pipe and re-buying the whole mess. I figured it out, and will shoot some pics and send them to you later today via this thread.

[Flynavy]

Thanks Phrumes.
I spent an hour and a half at the local RV store today and all I acomplished was get a headache. We went through the catalog and looked at all the fittings on the shelf, and while I think it can be done, we couldn't figure out how to keep the pipe inside the bumper compartment.

Looking forward to seeing how you did it.

[Phrunes]

Ok FlyNavy,
I'll try to make sense of these for you. Here is where I deviated from the norm:

On the hose end it goes thru the bumper on the street side of the trailer...I added a screw type fitting in the three inch pipe. That way, I could seperate from the complex bend assembly shown.

I added industrial slip compression fittings just before each valterra flange at the rear. That way, if a valve failed, I just have to replace a $2 valterra flange fitting and a short piece of pipe or just the defective valve, or just the forward flange and small piece of abs at the holding tank...Lot's of fleibility here. If you glue it all together and one valve were to go bad, you'd have to rebuild the entire assembly from scratch. Which sux, I know because I built this thing three times with glue before I finally settled on the compression fittings! Home depot loved me.

My system is as follows:
3" PVC and Valterra on black tank
2" PVC and Valterra on gray tank

Both collect into a 2" into 3" x 3" cleanout fitting and exit the bumper with 3" hose fitting.

Hope these help, don't hesitate to ask more questions if you have some.

[Flynavy]

Although my layout is different that is what I am trying to accomplish. I need to get a 3x2 Y fitting and see if I can't work that out. Biggest prob. I've got is I do not have anyplace to put the slip fittings. My black valve goes straight into an ell, and the gray valve goes straight into the Y. There may not be enough room to add slip fitting.

Thanks for putting up the pics.

[jkcru]

Try the plumbing supply houses, those fittings are aviable in flexable neoprene with clamp connections

[Flynavy]

Sucess!!!! (at least I think so).

It looks to me like this is gonna work, using Valtera valves. I needed to find room so I could use slip couplings for future maintenance. AS had two 3" ells back to back coming straight out of the black tank. I'm going to do the same except I'll use two street ells with the slip ends faceing each other conected by a slip connecter.

AS used a 3x3 Y to pick up the gray tank which has a 2" drain. I'm going with a 3x2 Y with a 2" street 45 to pick up the gray. That leaves me enough room to use a 2" slip connecter behind the dump valve.

At least it looks good laid out on the shop floor. I have to replace some floor before I start putting it back together, but I think it is gonna work. I'll put up some pics when it's done.

[Phrunes]

Woohoo!....Don't glue it till it's in though!

Here's my old one...new one is same layout with valterras, slip joints and I changed gray to 2" all the way.