My 3" Valterra Black Tank Valve Leaks - Needs New Seals

Updated 05/12/2025 | Published 05/15/2021

Products Featured in This Question

Valterra Bladex Waste Valve Body for RV Black Water Tank - Aluminum Handle - 3" Diameter

(683)

$20.62

Swivel Stik RV Black-Water Tank Rinser

(56)

$35.02

Replacement Seals and Hardware for 3" Valterra Waste Valves

(45)

$11.86

Question:

I just removed it and there is a 1/16inch on the sides of the blade. How can there be a gap along the sides of the blade and it still seal from leaking through? The pictures on your website also show a gap on each side. Please explain how it is supposed to seal. My valve just has hard plastic the the blade glides on. There is no rubber seal. It appears according to your pictures they are made that way. I dont want to buy a new one and still have gaps where raw sewage can leak through. Luckily the cap seals great but it is a mess at the dump station!!

asked by: Herb G

Expert Reply:

As a clarification, all valves, including the # T1003VPM, include seals, as pictured in picture 10 on the product page.

However, I can see that your 3" waste valve is missing it's seals. I would not buy a new complete valve when all you need are the replacement seals. Valterra makes two Replacement Seals & Hardware kits for their valves. The # T1003-7VP is for "old style" Valterra valves made prior to 2000, and # T1003VPM is the current style that fits Valterra, Bristol, Bladex, and Anonda valves.

Unless someone installed an old style valve on your 2019 Winnebago, you probably have the new style.

With your defective waste valve draining off the liquids from your black tank you may have some solids left behind that may need some encouragement to move along. You should consider the Camco # CAM40094 "Swivel Stick" tank rinser. You will want to flush and drain a few times before taking that valve apart! If it were me the fill for flushing would include a water/bleach mix for some level of sanitizing.

expert reply by: Les D

Fred

6/5/2024

Les, You caught my attention when you were talking about the older style valve. A friend of mine was helping me replace the seals on a 1 1/2 inch grey valve. But the seals turned out to be thicker than the seals that were in the valve. Consequently he couldn't get it to work properly and wound up putting the old seals back in there to close it up. Of course now it leaks worse than it did before. Are the older style seals thinner than the new style seal? Can you give me the link for the holder 1 1/2" seal kit please. The valve is 1 1/2" Valtera cable My 5th wheel is 2006 Dutchman. Thanks!

Jameson C.

6/5/2024

@Fred We currently only have one 1-1/2 inch seal for Valterra valves with the part # T1001-9VP. We don't have an older style size seal so worse case scenario the valve has to be replaced.

Steve W.

4/30/2025

You did not answer Herb G's question! How does the new valve seal when there are 1/16" gaps on both sides of the blade???? The whole point of having a valve is so it holds the waste back while you are setting up the hose at the discharge station which requires removing the cap WITH NO DISCHARGE UNTIL THE VALVE IS OPENED! if the valve does not keep ALL the waste from discharging, there is no point in having one! So, again: How does this valve seal when there are 1/16 gaps on each side of the gate/blade?

Kate F.

5/12/2025

@SteveW Let’s talk about how the Valterra # T1003VPM Bladex 3" waste valve seals properly, even though it might look like there are 1/16" gaps on each side of the blade. That definitely sounds concerning at first, but there’s actually some clever engineering at work! So here’s how it works: inside the valve, there are two specially designed Buna-N rubber seals, one on each side of the gate blade. When you slide the handle to close the valve, that blade gets squeezed tightly between those seals. Even though there’s a bit of clearance to let the blade move smoothly, once it's in the closed position, the rubber compresses around it to form a nice, snug, watertight seal. No leaks, no smells..... just solid performance. The seals are molded with just the right amount of give to close that gap you noticed. If you're ever doing maintenance or a replacement, there’s even a seal kit (Valterra # T1003-9VP) made just for this. It comes with both seals and all the hardware you need, super convenient! Quick tip for installation: when putting in new seals, it helps to dab a little petroleum jelly on them. That keeps them in place and helps everything slide together neatly. And definitely make sure the seals are seated properly, alignment is key to keeping things leak-free. Also, just like anything on your RV, regular maintenance is a great idea! Take a peek at the seals now and then, especially if the valve starts to leak or feel sticky. They’re easy to swap out, and keeping them fresh will help your black tank system work like a charm. If you need more details than that, then you might want to reach out to the engineer to get his top secret drawings =)

Steve

5/12/2025

@KateF Thanks for a great answer! I now see how this works, installed a replacement and it works perfectly! Thanks!