Fixing Stuck 1.5" Bristol Gray Valves ( 315RLTS )

[howson]

Kitchen Gray (Follow Up from post #9)

Finished up the Kitchen gray valve today. I found the same corrosion on the cable rod (after a complete disassembly of the rod and sleeve assy). I sanded off the major rust and lubricated the sleeve (and rod) with Motion Pro Cable Lube. Works great on a motorcycle cable...so hopefully helps keep the dump valve steel rod from rusting quickly again.


I also shortened the cable but neglected to measure the new length. It's now just one gentle turn from the handle to the valve instead of a 96" long looping mess.

Update 30 Aug 2020: The Shop Straw idea to lubricate the valve easily didn't work out--the back pressure caused leaks and other anomalies. I ended up putting a small screw into the hole I'd made in the valve body (as shown in many YouTube videos by others who first came up with the method). BL: I removed the Shop Straw pictures and text.

I also finished up making new handles. There's a separate thread on that issue: https://gdrvowners.com/forum/operati...s-easy-to-make

Howard

[Cate&Rob]

howson
Hi Howard,

For the spray lube to go in . . . air in that cavity has to come out . . . how is that space vented?

Rob

[howson]

howson
Hi Howard,

For the spray lube to go in . . . air in that cavity has to come out . . . how is that space vented?

Rob

The space between where the hole is made and the knife valve is not sealed to the point where lubricant can't pass.

The first hole and test was on the bathroom gray valve. When I sprayed lubricant using the hole it seeped all the way through to the knife valve. I witnessed it. The valve was in my hand as I did it. I could have kept spraying until the can was empty if I'd wanted to.

Adding lubricant in this manner is not a new method. There's a plethora of YouTube videos showing the same concept. I found through my own testing that it does indeed work (at least on a Bristol 1.5" valve).

When I drilled the same hole in the kitchen gray I did so without taking the valve apart. The valve does, however, work much better after introducing the lubricant through the hole I drilled. "Much better" is such an ambiguous term--wish I had a pull meter to measure the difference I can feel. Note the "work better" valve operation is independent of the cable/sleeve problem. I didn't have the cable/sleeve connected when I first introduced the lubricant into the valve.

I hope that makes some sort of sense...time for this 'ol boy to get some shuteye.

[ThePowells]

howson Thanks for the straw idea. I know that I have to spray my blade valve that is exposed almost every time that I need to dump the black tank, but it may be that I need to use a different lubricant.

[howson]

Bathroom Gray (Follow up from post #16)

28 Oct Update: This post had pictures and notes for installing a "shop straw" into the hole for the lubricant. That idea was a flop--deleted the errant pictures and text. I installed a small screw in the hole drilled in the valve to keep it from leaking (as shown in multiple YouTube videos).

Howard

[howson]

Got a leak, dang it. It's on output side of the bathroom gray valve (the one I disassembled). I found the leak when I opened all the gray valve tanks to "equalize" them (with the Valterra on the exit closed). To my surprise the valve started to leak (it didn't with water in the tank and the valve closed). That leads me to believe the gasket on the output side isn't seated correctly or is bad.

I've ordered a new Bristol valve and replacement parts for a Valterra. I'm going to try the Valterra gaskets first. It that doesn't work...I'll attempt to install 1/2 of the new Bristol along with it's new gaskets. As I noted in this thread earlier, I don't think replacing the entire Bristol is possible due to the way GD installed it (glued right to the tank).

If it still doesn't work, I'm going to have to get creative. I am not replacing the tank.

There's a temptation to leave it as it is, but there's always going to be some equalization when tanks are dumped which will result in a small amount of leakage. I can't leave it like that.

[ncitro]

Got a leak, dang it. It's on output side of the bathroom gray valve (the one I disassembled). I found the leak when I opened all the gray valve tanks to "equalize" them (with the Valterra on the exit closed). To my surprise the valve started to leak (it didn't with water in the tank and the valve closed). That leads me to believe the gasket on the output side isn't seated correctly or is bad.

I've ordered a new Bristol valve and replacement parts for a Valterra. I'm going to try the Valterra gaskets first. It that doesn't work...I'll attempt to install 1/2 of the new Bristol along with it's new gaskets. As I noted in this thread earlier, I don't think replacing the entire Bristol is possible due to the way GD installed it (glued right to the tank).

If it still doesn't work, I'm going to have to get creative. I am not replacing the tank.

There's a temptation to leave it as it is, but there's always going to be some equalization when tanks are dumped which will result in a small amount of leakage. I can't leave it like that.

Boy that’s a bite. Nothing worse than being all wrapped up and feeling good about a job and then having an issue. I agree it needs to be dealt with. Hope you can rebuild the one that’s there.

[StephenO]

Got a leak, dang it. It's on output side of the bathroom gray valve (the one I disassembled). I found the leak when I opened all the gray valve tanks to "equalize" them (with the Valterra on the exit closed). To my surprise the valve started to leak (it didn't with water in the tank and the valve closed). That leads me to believe the gasket on the output side isn't seated correctly or is bad.

I've ordered a new Bristol valve and replacement parts for a Valterra. I'm going to try the Valterra gaskets first. It that doesn't work...I'll attempt to install 1/2 of the new Bristol along with it's new gaskets. As I noted in this thread earlier, I don't think replacing the entire Bristol is possible due to the way GD installed it (glued right to the tank).

If it still doesn't work, I'm going to have to get creative. I am not replacing the tank.

There's a temptation to leave it as it is, but there's always going to be some equalization when tanks are dumped which will result in a small amount of leakage. I can't leave it like that.

Well, like Red Green or my Father in Law might say, "just put some duct tape on it!". Just kidding, and that does suck. Good luck, and let us know what you find! Considering all the upgrades you just did though, only having this leak is not bad.

[howson]

The Valterra replacement is not going to work. As you can see in the pictures below, the mounting configuration is too different. Without a better technical explanation...the only way I can describe the inner edge near the knife valve that the seals mount against is the Bristol is an "innie" and the Valterra is an "outie". (No doubt the engineers are impressed by my grasp of technical terms.) So even if I could line up the new Valterra the seals likely wouldn't work with the Bristol flanges (that are glued to the camper's ABS). Look closely at the picture below and you'll be able to see exactly what I'm referencing.

Finally, the seals on the existing Bristol looked fine (you'll also see them in a pic below) so I reinstalled the valve and tried the test again--same result. Tank doesn't leak with the waste water in it and the valve closed, but once the valve is opened and the drain line fills water leaks out of the valve.

So now I wait for the new Bristol to show up...

[howson]

Funny how the mind works. Up at 2am for "old man relief" and it dawned on me what may be causing the problem.

In post 16 (the kitchen gray valve--the first one where I added a shopstraw) I superglued the straw into the valve body, using baking soda to create a hard bonded exterior. Ugly, but effective since it sealed the junction. Pictures and text were subsequently deleted as it was not a good idea!

In post 20 I added a shopstraw to the bathroom gray but did not superglue the straw to the hole I'd made in the valve--it is just inserted the straw and then secured it to the sleeve body. Pictures and text were subsequently deleted as it was not a good idea!

So how is this connected to the leak? Water was seeping out around the straw where it was inserted into the valve body!

Think about it--when the valve is closed, the knife valve keeps any water (on either side) from passing the seals. When the knife valve is retracted (valve open) the cavity the knife retracts into is not sealed--water can get in. With the hole for the shopstraw unsealed, water under pressure (since I had the output Valterra valve closed so all the tanks would equallize) came out of the unsealed hole.
All I did was pull out the straw and insert a screw. No leak.

Brings up a caution regarding the common advice to open the gray valves with the add-on (at the dump exit) Valterra closed to allow for one big gray tank. By opening the gray valves without allowing water to drain out, dirty water is unquestionably getting pushed into the knife valve cavities, potentially allowing a build up of gunk which then could affect the operation of the valve.

Another day, something new learned...

Howard