Blk/Grey Dump Valve Changout

[Chickadee]

G'morning:

Have 08 Ex and might need to replace (changout) one, or both, black and grey tank dump gate-valves (ie. Valterra Bladex Valves 3" (blk), 1 & 1/2" (gray).

(Went to dump grey tank and discovered quite a load of liquid (gray or blk..not sure) inside the expandable sewage dump hose which I'd left attached but capped to exit port with both gate valves closed. Either gate on one or both weren't closed tight or one or both leak!)

Question: Process looks simple enough, (empty tanks, loosen & remove the four bolts securing gate valve to tank drain pipe(s), install new gate valve(s), etc.)....BUT....thought I'd better ask for experienced input, if there might be any special step to be aware of before I take-er apart and re-install new valves????

For few months now I have noticed that the black gate valve slides almost closed but then has to be rather forcefully pushed hard to seat something with kind of a snap feeling as if some rubber feeling seal is binding before seating in some groove. So now when I found liquid in the expandable drain hose I pch'd both gate valves figuring I'm about needing to replace one or both.

Thanks for any suggestions or advice. Steve

[Rick Long]

Be Prepared!! I did mine a few months ago... I thought I had flushed it enough. There is no such thing as enough!!!! Put a bucket or pan under the valve before you remove it and be prepared for some very nasty stuff. Not hard to do... just disgusting!

[Norm4015]

Flush and flush the tanks, then flush one more time. After the liquid stops dripping out, use the jacks to raise the side of the motorhome with the valves. That way you will get no more drips. Use gloves and when you install the new valve(s) make sure the O-rings are seated. It is usually an easy job, but a few times I have run into problems like the parts don't line up straight.

[Dr4Film]

Hi Steve,

I did mine a few months ago on my Monaco Windsor. The black had leaked a couple of times and it was getting a little stiff at the very end of the close stroke. Plus both handles had broken off making it difficult to use them. I had the valves in my storage bay already anticipating this project so on a decent day I decided I was going to tackle the project. Fortunately, my tanks are such that when you empty them, they are empty, not much for dripping although I put down a bunch of paper towel to catch any annoying drips. Took everything apart. My black valve was on the left and the grey valve was on the right with a T in the center that directs the waste out of the service bay. the T will come out with the valves. When everything came apart it was fairly easy to disassemble as it only required a little force to separate everything. However, when assembling the entire package, that's what separates the men from the boys. I had to do it twice as one rubber seal on one side had moved ever so slightly preventing the valve from working smoothly. Make sure the valves are closed when installing and the most important thing to get right is to make sure each seal, there will be four, two for each valve, stays in the correct position. Once you are confident that the valves and seals are all in and aligned correctly, now you will have to be a contortionist to get some of the hardware together. Tighten it all and make sure the valves are not binding and they should pull and push easily and smoothly. The new valves I put in had replaceable metal handles and the old original ones had plastic which had been broken years ago. Now you will need to test the valves before actual use. So, run water into the both the black and grey tanks, I would say about 10-20 gallons to get some real pressure behind it to see if the valves are leaking or not.

Glad I did mine on my terms versus having to do it when it actually failed. It makes life easier that way. The new valves actually work so much easier than the old original ones that sometimes I have to be careful when working inside the service bay or cleaning the bay and accidentally nudging the valve a little with my arm or elbow as they move with very little effort.

Good Luck!

Dr4Film ----- Richard.

[Chickadee]

Richard (Dr4Film): HEY!!, thanks!!! "You-da-man!!" Great description. Yeah, I too picked up the needed valves but figured I'd wait till......"later"...... to do the change-out, but due to your GREAT and encouraging description, well...now I guess I'll have to tackle it also. Thanks again, so much!! Steve

[deadeye916]

I removed and cleaned mine. The flap (disk) that opens/closes the valve seats into a ridge in the assembly when closed. Debris can get caught in the ridge when you dump. You would notice the valve requires more effort to completely close it that last 1/8th inch.

I flushed out the tank then removed the valve assembly and cleaned the ridge. No more leaking and the valve closes easily all the way. I've heard the ridge can be cleaned with a coat hanger or similar without removing the valve but I couldn't do that with mine and the gray and black use the same exit point to the hose via a "Y" pipe.

[Chickadee]

Dan & Jan (deadeye916):

Thanks!! Ya know, I wondered whether debris might be the problem. When I get into this changeout, maybe, I'll only have to clean out that ridge you described and can save my new valve's for backup. Thanks again. Steve & Lynette

["007"]

After you empty tanks try a water hose with high pressure nozzle on it and force water in slot with blade partially closed and see if you can remove blocking seat problem of blade. If you have a water wand used for cleaning up bottoms of water heaters for removing sediment may work also.
If it works spray some silicone on blades and work back and forth to make them work easily.

[puttin]

When I did mine on the old coach- it was easy, but since then, I've seen the "rv doctor" and others recommend greasing the valves with lithium grease before you install them....sounds like a good idea to me.