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Topic: Recent third dump valve installations (split from another topic) (Read 5393 times) previous topic - next topic - Topic derived from Please confirm waste ...

Re: Recent third dump valve installations (split from another topic)

Reply #50
Chuck, maybe I should have spoken to you before I did this, but have read so many horror stories on dump vlaves not opening and of course, you know this only happens when the tanks are really full to the brim!  Don't even want to deal with that issue!  lol


Been there, done that many times.  Take a drill, drill a hole, drain the fluids, then take it apart.

Rubber gloves and a hazmat suit!
Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348

Re: Recent third dump valve installations (split from another topic)

Reply #51
The Rubber Liner
Mine was in pretty good shape but to get at the main valves it had to come off.  Some careful easing it off with a long thin scraper did the trick.  Glued on with some sort of contact cement.  Mine had no tears in it and it cleaned up well so I just reused it.

The Cable Attachment Extensions to the Valve Body
I bought valve bodies ready for the cable wire and reused the original cable attachment extensions. Much cheaper that way.  Unless yours are broken there is no reason not to use them.  Same with cables.  They appear to be stainless steel.  Mine were in good shape.  I cleaned and lubed them well.  I painted the gray water tank valve handle gray. 

Third Panel
The third panel is a 90° piece that extends the back wall up another 4" and then out towards the outside of the coach about 9" to the bottom of the slide opening reinforcement. The 2001 coaches with slides have some extra structure under the slide opening the extends down into the bays. My first picture shows the water fill mounted in this structure, basically a truss made of steel tubing.  My water fill and water pump switches are mounted in this above the waste half of the bay.  This structure takes up about 1/3 of the height of the bay. 

As I am discovering as I meet more owners and see their coaches, there are many differences from year to year and even within years.  Dave M has the exact same coach as mine (expect for everything he has done to his and I have done to mine) and they are only a few build numbers apart but many small things are different. So be inspired and measure carefully since yours will be unique.

I will send a sketch of my metal parts.they are pretty simple, most any shop can fabricate them for you.  Stainless is tough to work with.  14 ga is about 0.08 inches and it was hard to drill the bigger  1-1/8" and 5/8" holes and hard to saw the openings.  It would have been much easier to work with steel and then (harder) to get them powder coated.  Cost would have been about the same.

Roger


Hi Roger,
A couple of quick newbie  questions. When you change out a blade valve. What is the process? Is that valve glued in? What do you use to lubricate the cables? I have a single valve and it's pretty difficult to operate. Thanks.
2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee

Re: Recent third dump valve installations (split from another topic)

Reply #52
The blade valve housing is between two flange fittings. The flange fittings are glues to the pipes on either side.  There are four bolts that go through the four corners of the flanges and blade housing to hold it all together.

There is a large o-ring on either side of the valve housing that fits into a mating grove on the flanges.  Hold it it place with plumber's silicone grease.  Use the same grease to very liberally lube the sliding part of the valve and the rubber seals on either side.

Make sure the o-rings are seated properly.  If not it will likely leak.  The hardest part is getting at the nuts and bolts, a long extension for the sockets or a flexible one helps. I replaced the nuts and bolts with stainless ones ans used an anti-seize lubricant on the threads.

Empty your tanks as best you can, add more fresh water and empty again.  Both of my tanks empty towards the driver's side. I leaned the coach hard to the passengers side and then started disassembling.  I stuffed a rag in the pipes to stop any leaking or smells.

I removed the pipes and valve assembly from the tanks to replace the valve bodies. Easier to do outside of the coach.  Then I cut the old original hose connection fitting off and glued on a new flange for the third valve.  Then it all went back in with shallow aluminum trays under the valves to catch any leaks and reattached to the tanks with the hose clamps.

The valve cable housing is clamped in the valve body, and a set screw holds the center cable.  If the set screw is loosened you can pull the center cable out with the handle. I used a spray lithium grease for lube.  The little red tube will push grease through the spiral housing,  I have re-lubed the cables a couple times.

While you are in there clean everything as best you can.  Leave some way to look inside to check for leaks.

The third valve is a useful project. It really is in spite of what others may so I will just put a line through it. You may not need one with just a single combined tank but the third valve also provides an extra protection from a failed or leaking primary valve.  Most of us have two waste tanks.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Recent third dump valve installations (split from another topic)

Reply #53

Res777 has a 2008 Nimbus, so the utility bay is likely different than a 2001.  I recall with the 2002-2005 year coaches, one cannot install a 3rd valve easily and still have the utility bay door close with the dump hose attached.  The dump piping needs to be cut quite a ways back for that to work.  2008 may be even different.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Recent third dump valve installations (split from another topic)

Reply #54
Res777 has a 2008 Nimbus, so the utility bay is likely different than a 2001.
Res777 says (Reply #51) that he has a "single valve" (and I would assume a single holding tank) so yes, quite a bit different.

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Recent third dump valve installations (split from another topic)

Reply #55
Res777 has a 2008 Nimbus, so the utility bay is likely different than a 2001.  I recall with the 2002-2005 year coaches, one cannot install a 3rd valve easily and still have the utility bay door close with the dump hose attached.  The dump piping needs to be cut quite a ways back for that to work.  2008 may be even different.


My wet bay has a small storage area in the upper right corner about 1'w x 6"h x 1'd. There's not much room in there. I haven't had the opportunity to remove the panels and look around. But I was curious about blade valve replacement. Now I understand.
2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee

Re: Recent third dump valve installations (split from another topic)

Reply #56
I was curious about blade valve replacement. Now I understand.
Roger (Reply #52) gave a very good explanation of the valve replacement process.  For those who, like me, are more visually oriented learners, there was a timely post on the RV Tip of The Day web page.

https://rvtipoftheday.com/rv-repair/how-to-replace-rv-waste-dump-valve/


1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Recent third dump valve installations (split from another topic)

Reply #57
Changing the blade valve and lubing the cable was the primary question. Doesn't matter what coach, but relevant as long as the valves and cables are the same.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Recent third dump valve installations (split from another topic)

Reply #58
Res777 says (Reply #51) that he has a "single valve" (and I would assume a single holding tank) so yes, quite a bit different.



So, yeah, third valve doesn't apply in that case  ;) 
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Recent third dump valve installations (split from another topic)

Reply #59
Inspired by Rogers really nice work and post 8 years ago, I'm updating my wet bay too.  Thanks Roger for the post and the detailed description along with parts list.  Lonnie
Lonnie & Sherri Williamson
2000 U320 36'

Re: Recent third dump valve installations (split from another topic)

Reply #60
How cool to be able to help others.  We just don't realize how our time & good deeds can carry forward.
Lonnie & Sherri Williamson
2000 U320 36'

Re: Recent third dump valve installations (split from another topic)

Reply #61
Off topic posts removed by Moderator Jeff.
1993 U300 40ft GV SE
Build # 4344

Re: Recent third dump valve installations (split from another topic)

Reply #62
Inspired by Rogers really nice work and post 8 years ago, I'm updating my wet bay too.  Thanks Roger for the post and the detailed description along with parts list.  Lonnie
Lonnie, I don't know if your coach has a slide, but if it does this is a must do modification. 2001 slide truss they installed makes it really a challenge to remove unless you weigh 120 lbs. very difficult to get below the truss and above the panel to disconnect the cables. Electric valve would help  access but what a pain. Good looking panel. If you dont have the truss issue then it doesn't need to be three panels. Very nice job either way. If that is stainless it was a lot of work! 👍👍
Scott

Re: Recent third dump valve installations (split from another topic)

Reply #63
No slide on our coach Scott and good thing because I'm pushing double the 120.  I just had a valve cable issue and decided to just replace it all along with adding the the 3rd valve and couldn't resist the stainless panels.  I can't take credit for the nice cut outs.  I went to a local sheet metal shop and they used their cnc plasma table.  I hope to have everything back in place mid next week if time allows. Thanks for the feedback. 
Lonnie & Sherri Williamson
2000 U320 36'

Re: Recent third dump valve installations (split from another topic)

Reply #64
That's cheating. I like it but I seem to never go down the easy path. All I could think of was all time spent cutting by hand. I really like the third valve and use it every single time I dump. I always run my potable water into the gray tank before getting home. Dump the black and back fill with the extra gray tank. Usually get three back flushes on the black tank. Always crystal clear on the last backflushes. I never added a black tank cleaning spray tube as others have but seems to be clean and odor free. I did recently change all my air admittance valves inside do to odor oddly during dump events inside. Resolved issue. I always dry out the potable water system during extended storage periods. Nevertheless your panels look great. You should post a link to the sheetmetal shop, others may want to do what you did and since its loaded in there programming it would be simple for them to build panels for others and ship.
Scott