Gray Valve Size

[mdelaven]

Need to replace the Gray 1 Dump Valve on 2019 Momentum 397th I found 2 sizes 1 1/2" and 3"
Thanks

[ThePowells]

Welcome to the forum. Dump valves are 3 inches.

[mdelaven]

Thank you!!

[Country Campers]

Looking at some of my factory pics the grey tank valves for the kitchen are 1-1/2" valves. I do not have any Momentum pics to go by. I would suggest if you can to get a peak at the valve before ordering the one you need. Or if you buy one of each size you would have a spare of one size. Another note would be I think GD does not use Valterra valves and I am not sure if all valves are interchangeable.
The valves are also not glued to the tank. There is a large hose clamp and butyl putty around the connection for sealant.

Brian

[howson]

ThePowells &
mdelaven

Black tank dump valves are 3". Gray tanks use the smaller 1.5" valves. (I double-checked the 397th drawings to make sure it was the same as it is in my 315RLTS.)

The valve can be either Valterra or Bristol--unless you're lucky they will not be interchangeable (I know from first hand experience).

Howard

Edit: Brian beat me to it!

[howson]

mdelaven -- if your trailer has Bristol valves and they are glued on (like mine were) my experience documented in the thread below may be helpful. Any questions...fire away.

https://gdrvowners.com/forum/operati...valves-315rlts

[Cate&Rob]

mdelaven

You can determine the size of the gate valve by how far the pull handle moves. 3” or 1 1/2” ? Our shower grey is a 3” valve and our galley grey is a 1 1/2” valve.

Rob

[ThePowells]

I stand corrected. I guess I need to leave the technical parts posts alone since their is such a wide variety of applications across the lines. Both of my grays are 3".

[Country Campers]

I stand corrected. I guess I need to leave the technical parts posts alone since their is such a wide variety of applications across the lines. Both of my grays are 3".

It is entirely possible that the grey valves and black valves are different sizes among the different lines , Momentum , Solitude may have all 3" valves while others may have both. Just trying to add input that "check the size first" may be the best option.

GDRV-Megan

Could you please confirm the size of the dump valves throughout the different lines? Both grey and black.

Brian

[howson]

I stand corrected. I guess I need to leave the technical parts posts alone since their is such a wide variety of applications across the lines. Both of my grays are 3".

Sometimes posts that seem "wrong" lead to very interesting discussions or discoveries--don't hesitate to keep posting, Jerry!

In this case the drawings the moderators have access to for the 390RK date back to 2017. The drawing shows 1.5" valves for the gray tanks and 3" for the black. Very interesting that you have 3" for all of the valves.

I don't know this, but when yours was manufactured they may have run out of a component needed for the 1.5" setup or a number of other reasons that drove them to make the entire system 3".

Bet it's fast dumping the gray tanks with 3" valves!

Howard

[GDRV-Megan]

It is entirely possible that the grey valves and black valves are different sizes among the different lines , Momentum , Solitude may have all 3" valves while others may have both. Just trying to add input that "check the size first" may be the best option.

GDRV-Megan

Could you please confirm the size of the dump valves throughout the different lines? Both grey and black.

Brian

Sorry, I don't have that info.. I would recommend reaching out to our parts dept with VINs to verify. Not every unit is going to have the same parts, especially with different suppliers running out of products so often.

[ThePowells]

Sometimes posts that seem "wrong" lead to very interesting discussions or discoveries--don't hesitate to keep posting, Jerry!

In this case the drawings the moderators have access to for the 390RK date back to 2017. The drawing shows 1.5" valves for the gray tanks and 3" for the black. Very interesting that you have 3" for all of the valves.

I don't know this, but when yours was manufactured they may have run out of a component needed for the 1.5" setup or a number of other reasons that drove them to make the entire system 3".

Bet it's fast dumping the gray tanks with 3" valves!

Howard

The mothership just sent me a replacement valve for the #1 gray tank and it was a 3". I haven't seen one for the #2 gray, but I know that the stroke is about 3", and the fresh dump is 1 1/2.