Waste valves 1991 excella 25'

[TOPORANGER]

Hi everyone.

After reading others how to's on replacing waste valves, I have started on my leaking black tank valve. As long as I am at it I am going to do both valves.

Cleaned black tank using lots of water, then soapy water and bleach and then more rinse water, I filled and rinsed tank a total of 5 times.

First off is the issue of cutting an access hole to get at the valves. I decided on 20" by 20". Started with a 3/8" drilled hole and then used an electric nibbler to make the cuts in the pan metal. I highly recommend the nibbler, its fast and safe. Buy, rent or borrow one if you can.

I have included some pix from my project, with more to follow as I proceed.

First is of the nibbler I used, for people who are not familiar with that tool.

2nd pic shows the original valves in place after the access hole was cut.

3rd pic shows black tank with valve removed, and that's the tank rinse device mounted high on end of tank. Tank rinse device was not working, so out it comes.

4th pic is of the device after removal.

5th pic shows inside of brass fitting that screws into rinse device. It had a large deposit of corrosion in the bore. The rinse device itself was blocked by a combination of teflon thread tape, (nice workmanship there AS) and black flakes of something I was not able to identify. Once out and disassembled it was easy to clean the spray holes.

6th pic of cleaned device.

More to follow.

[TOPORANGER]

After valve removal, I noticed a buildup of something in the black tank. No not THAT!!, I will describe it as a crystalline type deposit within the tank. It is hard to the touch and flakes off easily. It is a navy gray in color. As I was flushing tank I had noticed a small amount of this stuff coming out of dump hose. On the valve seal itself it really looked like a growing crystal deposit.

As this stuff is flaking off and is hard enough to damage valve seals I will have to figure out how to get it out of tank. I am going to experiment with trying to dissolve it in different chemicals I have in the shop.

Friends I have asked what they think it is, have come up with:

1 Tank Leak sealer? (I have not found any evidence of tank having leaked)
2 Deposit from something former owner used in tank to control odor, soften water??

Included pic of the nasty stuff. This deposit was directly next to valve in the throat of the tank exit. Largest piece I have found. Most of the deposit is much thinner in thickness, than pictured here.

Anyone else have this problem?

[A W Warn]

Thanks for the photos, and looking forward more. I've got this same project to do early this fall when it cools off.

I'll guess that is the residue left from Rid-X, a granular enzyme additive product made for use in septic tanks (not in RV wast tanks). In order for it to work it has to be dissolved so that the enzyme is activated and left in the tank long term so that the enzyme can do it's thing. If it is not completely dissolve the granules stick inside the black tank when the tank is drained, then left to dry. I was guilty of trying that a few times to try to remove a buildup of stuff inside my trailer's tank right under the toilet.

I now use the Geo Method and all of the stuck on debris in my tank is gone. I can see clean plastic. This is what I suggest you should do.

Again, it's just a guess about the buildup in your tank.

[TOPORANGER]

Good News!

Vinegar breaks up the deposit. Did not totally dissolve it, but, broke it up into tiny grains. I am going to get a bunch and put in the black tank to attack the deposit.

[ChrisPBacon]

Originally Posted by TOPORANGER

After valve removal, I noticed a buildup of something in the black tank. No not THAT!!, I will describe it as a crystalline type deposit within the tank. It is hard to the touch and flakes off easily. It is a navy gray in color. As I was flushing tank I had noticed a small amount of this stuff coming out of dump hose. On the valve seal itself it really looked like a growing crystal deposit.

As this stuff is flaking off and is hard enough to damage valve seals I will have to figure out how to get it out of tank. I am going to experiment with trying to dissolve it in different chemicals I have in the shop.

Friends I have asked what they think it is, have come up with:

1 Tank Leak sealer? (I have not found any evidence of tank having leaked)
2 Deposit from something former owner used in tank to control odor, soften water??

Included pic of the nasty stuff. This deposit was directly next to valve in the throat of the tank exit. Largest piece I have found. Most of the deposit is much thinner in thickness, than pictured here.

Anyone else have this problem?

This might help explain what it is!
What is Struvite
TankTex RX
https://youtu.be/XPEb5m5z4U8

[ChrisPBacon]

TankTex RX What is Struvite ?

https://youtu.be/XPEb5m5z4U8

This might help to explain what it is, I've used it and it work for me...

[harryk]

I have a 93 and both valves have a slight leak. When you get time, I would appreciate more pictures of the pipe & valves maybe looking up from the ground ? (real nervous about tackling this repair)

[A W Warn]

I found some good photos here
http://www.airforums.com/forums/f444...ed-139672.html

[TOPORANGER]

I have put vinegar into black water tank, to soften the deposit. Heated the vinegar first, it is working really well at breaking up the deposit. I put old waste valve back on temporarily. I am waiting on the Valterra valves to be shipped. I found some on eBay that have a drilled stem, that use the original handle extensions. Well that did not work out. The seller had a 4 day handling window. When the valves were not shipped after 4 days, I contacted the seller. He said that now the valves would ship on Aug 12, that is like 3 weeks. So, I cancelled that order and placed an order with another ebay seller for regular Valterra 3 inch valves. I will either drill the stems myself or make new extension handles.

I intend to reuse the 3 inch wye and most of the piping. Also changing the waste hose connection fitting from Thetford type to Valterra. Picture of cutting off the Thetford and dry fitting the Valterra to exiting discharge pipe.

[TOPORANGER]

The eBay purchased Valterra 3" waste valves arrived. I removed the plastic handles. I want to use the original Airsteam extentions and handles. Decided that the best results on drilling the stems would be done at a machine shop. So I took the valves to a local shop and they used a Bridgeport to drill the stems. Bit of overkill. It is important that the holes are centered on the stem. That is difficult to do by a novice. I suppose if you had a V block you could do it on a home shop drill press. Any way, the charge was 5 bucks, and the holes are perfectly centered. I say well worth it.

[TOPORANGER]

Here is a picture of the waste valve system ready for install.
I decided to use all new piping, as the joint in the existing wye for the grey water discharge did not clean up properly.

I installed the final discharge pipe after the installation of these parts. That way I could cut the exit pipe to position the terminus where I wanted it.

Note when joining ABS to PVC a specific cement must be used

[Sav'h Steve]

TopoRanger,

Thanks for taking the time to post your pics and progress!

I too need to do this for my '90 Excella 25. So mine *should* be the same as yours.

Because Thetford gates are 3X as expensive as Valterra, and I assume the original was pvc welded together, it seems to make more sense to replace everything after the tank adapter out to the end - the gate valve, wye collector for both tanks to outer connection.

Ques:
1. Does the new Valterra connect directly using the 4 holes on the tank adapter?
2. Valterra makes a number of different part numbers for their gate values. Which did you use?
3. After cutting the 20 x 20" access hole, what did you use to recover with? I of course assume you bought a slightly larger piece and riveted it back in.
4. Was there a problem using the original Airstream pull rod extensions on the new Valterra short rod?

Thanks, and if others who have done this repair have suggestions, PLease post! ~

[TOPORANGER]

[QUOTE=Sav'h Steve;1831307]TopoRanger,

Thanks for taking the time to post your pics and progress!

I too need to do this for my '90 Excella 25. So mine *should* be the same as yours.

Because Thetford gates are 3X as expensive as Valterra, and I assume the original was pvc welded together, it seems to make more sense to replace everything after the tank adapter out to the end - the gate valve, wye collector for both tanks to outer connection.

Ques:
1. Does the new Valterra connect directly using the 4 holes on the tank adapter?
2. Valterra makes a number of different part numbers for their gate values. Which did you use?
3. After cutting the 20 x 20" access hole, what did you use to recover with? I of course assume you bought a slightly larger piece and riveted it back in.
4. Was there a problem using the original Airstream pull rod extensions on the new Valterra short rod?

Thanks, and if others who have done this repair have suggestions, PLease post! ~[/QUOT

Q1) No the Valterra does not use the Thetfoprd tank adapter. I bought 4 each of 3 inch spigot adapter, $6.95 each free ship

Q2) Valve is part number V1003VP $15.03 each free ship

Q3) I have some galvanized sheet metal on hand for access panel. Have not yet installed it.

Q4) I had to have the valve stems drilled, as stated in earlier post. I highly recommend you have a machinist do it. Critical that hole be centered. Cost me $5 for both to be drilled. I had to adjust the mounts for the handle retention clips. Moved them about 3/4" outward.

Yes it is best to plan on replacing all plumbing parts. Original parts were ABS not PVC. New valves, spigots and hose connector are ABS new piping PVC. Be sure to get the proper cement for the ABS to PVC joints.

[Sav'h Steve]

Originally Posted by TOPORANGER

TopoRanger,

Q1) No the Valterra does not use the Thetfoprd tank adapter. I bought 4 each of 3 inch spigot adapter, $6.95 each free ship

Q2) Valve is part number V1003VP $15.03 each free ship

Thanks for your quick reply!

I did find the Valterra valve on Amazon for $18 (Thanks)

But I'm having some problem finding the *spigot* adapter.... and I thought you needed two. Did you get two spares?
Which sealer did you use behind the adapter to tank?

Can you suggest a supplier?
Steve

[TOPORANGER]

I got valves and spigot adapters on eBay

Vales from rvgod eBay seller name

spigots from circle_k_rv_parts_and_accessories

You need 4 spigot adapters, one for each side of each valve.

Shop harder you can get valves for less than $18

[TOPORANGER]

Not to forget but you will need a new sewer termination adapter hose connection, I chose to go with a Valterra style over the existing Thetford. Most modern rigs use the thetford. Part number T1029-2

From eBay seller schmukalyn $6.80 shipped

And a 3" bayonet sewer cap part number T1020, I got mine on eBay from camperparts123_jrshanon1 cost $4.69 shipped

I shopped hard on eBay for best price with free shipping. All parts from different sellers. No loyalty on my part. I will say that all shipped really fast and the parts were as described.

[TOPORANGER]

I used a silicon type sealer, not caulk, at tank connections. I had it on hand in the shop.

[Sav'h Steve]

Thanks for your help ! ! !

Steve

[Lumatic]

Originally Posted by TOPORANGER

[FONT=Tahoma]

1 Tank Leak sealer? (

Is there any such animal and what is the product name?

[TOPORANGER]

Originally Posted by Lumatic

Is there any such animal and what is the product name?

I did not mean that I know of such a product. These were just guesses by friends on what the substance MIGHT be