Valterra to Thetford connection - Page 2

Lumatic · 08-21-2008, 05:43 PM

I don't want to hijack this thread, but it does relate to the current status of my dump valve on my 71 I need to replace. Should I go with Thetford or Valtera?

Airtandem · 08-21-2008, 05:44 PM

I recieved mine from CW today it is their part No. 35555..Price $4.00 and $5.50 to ship.

Airstream 65 · 08-21-2008, 06:23 PM

Ok, here is a picture of my pipe.

clancy_boy · 08-21-2008, 07:51 PM

OK, that's unlike any I have seen - maybe my adaptor is not the one you need.

The one I have stated on the package is thetford to valterra adaptor.

DEITZ645 · 08-22-2008, 06:05 AM

Quote:

Originally Posted by Lumatic

I don't want to hijack this thread, but it does relate to the current status of my dump valve on my 71 I need to replace. Should I go with Thetford or Valtera?

Lumatic,
Since everything in the modern RV world seems to be Valterra, I would lean that way. Just easier all around, especially if you need replacement parts later on. Just my $0.02.

DEITZ645 · 08-22-2008, 06:23 AM

Quote:

Originally Posted by Airstream 65

Ok, here is a picture of my pipe.

Airstream 65,
That is like no other RV sewer pipe I have seen. From the picture, it looks like the flare at the end of the pipe goes all the way around. Was this at a permanent site? I am thinking maybe the flexible sewer hose was put over the flange and held on with a hose clamp.

This might work as a stop gap until you decide what you want to do. Measure the outside diameter of the pipe and head to the plumbing department of your favorite home improvement mega-wharehouse and look for a Fernco Coupling like this...

Then go to your favorite RV store and get a Valterra bayonet fitting similar to this one. I know it is threaded on one end and has a nipple to secure a cap, but you should be able to make it work with the Fernco Coupling.

I know this is not an ideal permanent solution, but it should allow you to at least use a Valterra sewer connection and dump your tanks until you can replace that "unique" sewer pipe.

balrgn · 08-22-2008, 06:29 AM

My Argosy 20 had a camaged fitting, rather than mess with it I repalced it. It's an option...

sander17 · 08-22-2008, 07:27 AM

Quote:

Originally Posted by DEITZ645

Lumatic,
Since everything in the modern RV world seems to be Valterra, I would lean that way. Just easier all around, especially if you need replacement parts later on. Just my $0.02.

I would agree. On our '96, the black tank thetford valve has had an ongoing problem of not sealing after a few uses. After removing and cleaning it several times, I added a third valve to the system just upstream of the drain hose fitting. I used a Valterra since all of the seals are attached to the valve mechanism with the pipe connections being just square flanges. If anything goes wrong, you just remove 4 bolts and replace the whole valve (at $13.50 instead of $45+ for thetford) Another maintenance bonus is that none of the fasteners are threaded into plastic.

Airstream 65 · 08-22-2008, 08:09 AM

Thanks everyone for the advice and the offers of parts! DEITZ645, it looks as though a temporary fix may be in order until I can do a complete replacement. The flare at the end of the pipe doesn't go all the way around though, there are four separate flares, but they are very thin. The second picture is a bit blurry, but it shows the grey water outlet downstream of the Thetford Valve. (Never thought I'd spend so much time taking pictures of a sewer pipe!!)

DEITZ645 · 08-22-2008, 08:19 AM

Airstream 65,

"Never thought I'd spend so much time taking pictures of a sewer pipe!!"

I have read a lot of threads about the older models not having a gray water tank and that it was just let to run out on the ground. I have never seen one, but it all makes sense to me now that I see how it was plumbed.

I think my Fernco Coupling idea would be a viable alternative until you work up the intestinal fortitude to drop the pan that covers your waste water plumbing.

Is there a cap that covers the pipe when not in use and in transit???

Airstream 65 · 08-22-2008, 08:37 AM

I'm going to try your Fernco Coupling idea. There was no cap/hose etc when I bought the trailer.

Ganglin · 08-22-2008, 10:00 AM

That may in fact be an original Thetford fitting - looks like they were changed in 1965 according to the VAC FAQ's page. Though someone here with a model in the early sixties should be able to confirm that (unless they have all been changed out). Not an answer for you but some background in any event. From VAC site:

Q: What’s with the older Thetford sewer fittings? Modern fittings wont fit.
A:1964 and older trailers have an older style of Thetford fitings than the later trailers. In 1965, Thetford changed the design, increasing the diameter of the lugs and sealing surface by an additional 3/8" in diameter. These modern fittings are still Thetford, which is the top-of-the-line fitting.

DEITZ645 · 08-22-2008, 10:06 AM

Quote:

Originally Posted by Ganglin

Q: What’s with the older Thetford sewer fittings? Modern fittings wont fit.
A:1964 and older trailers have an older style of Thetford fitings than the later trailers. In 1965, Thetford changed the design, increasing the diameter of the lugs and sealing surface by an additional 3/8" in diameter. These modern fittings are still Thetford, which is the top-of-the-line fitting.

Airstream 65,
I guess this would be the answer to why the Thetford to Valterra adaptor is too large for your sewer pipe.

Ganglin · 08-22-2008, 10:14 AM

Some replacement info. from the VAC on some older valves:

http://www.vintageairstream.com/FAQ/...dumpvalve.html