Main black tank valve not completely closing

RF_Burns

RF_Burns

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Sep 7, 2008
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So my black tank valve doesn't completely close. I can't get the retaining clips to snap over the handle. I'd say its less than 1/4" open, although
it doesn't seem to leak. I'm thinking there is some crud built-up in the end slot where the blade closure fits in.

Is it possible to remove the valve's shut-off blade out of the side of the valve so I can get a stiff wire in there to clean it? I'm hoping I don't
have to pull it all apart to get to it. :roll:

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
You have to pull it apart.

Emery Stora

>
> So my black tank valve doesn't completely close. I can't get the retaining clips to snap over the handle. I'd say its less than 1/4" open, although
> it doesn't seem to leak. I'm thinking there is some crud built-up in the end slot where the blade closure fits in.
>
> Is it possible to remove the valve's shut-off blade out of the side of the valve so I can get a stiff wire in there to clean it? I'm hoping I don't
> have to pull it all apart to get to it. :roll:
>
>
>
> --
> Bruce Hislop
> ON Canada
> 77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
> My Staff says I never listen to them, or something like that
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
> So my black tank valve doesn't completely close. I can't get the retaining clips to snap over the handle. I'd say its less than 1/4" open,
> although it doesn't seem to leak. I'm thinking there is some crud built-up in the end slot where the blade closure fits in.
>
> Is it possible to remove the valve's shut-off blade out of the side of the valve so I can get a stiff wire in there to clean it? I'm hoping I
> don't have to pull it all apart to get to it. :roll:

Bruce,

I am working at remembering how this all goes together. If it is an original Thetford valve, then it has to split at the face side of the entire
body. And that can't happen with the valve installed as it is also held together by the mounting screws. This is not sounding real do-able.

As I remember, what you would really like to do, just can't be done.
There is just no way to get at that.....

You could put a good cap on the outlet, put in some of the pot chemical that has a paper digester in it and fill the tank to the 3-1/2" level. Then
cycle the valve a lot. If you still have the Thetford flange - Katy bar the door - when you remove it...
I have a Valterra outlet flange and have a cover with a garden hose thread that I could work with...

Unfortunately, a Valterra valve just will not go onto a Thetford tank without some serious magic. I have been trying to design an adapter that would
cost less that a new Thetford valve, but it has been much harder than I imagined.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
If the pull handle & rod are original equipment, it may be that the jam nut has come loose and allowed the handle to rotate a couple of threads,
preventing the clips from going over the handle. Happened on my 77 Eleganza. Since the valve seems to be sealing, it's a possibility.

Hope that's it... no one likes working on that area of thee MH! John
--
John Shutzbaugh, Vacaville, CA, ncserv;
77 Eleganza, bought it new, can't blame PO, and
78 Buskirk stretch, "What were we thinking?"
 
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