GMCforum
For enthusiast of the Classic GMC Motorhome built from 1973 to 1978. A web-based mirror of the GMCnet mailing list.

Home » Public Forums » GMCnet » [GMCnet] Sewer Valve Replacement
[GMCnet] Sewer Valve Replacement [message #269444] Mon, 12 January 2015 07:10 Go to next message
Daniel DeLuca is currently offline  Daniel DeLuca   United States
Messages: 120
Registered: June 2014
Karma: 0
Senior Member
Hello,

My sewer valve leaks when it is being dumped, but otherwise is still watertight. I am putting replacing it on my “to-do” list. My coach appears to have the original Thetford valve. It seems that many people like to replace that valve with a more standard valve. Perhaps my google-fu is week, but I have not found instructions on how to do that. I have seen pictures, but I am wondering how difficult a job it is and what is needed. Since I am going to be doing this on my back, on gravel with everything a few inches above my head my primary concern is ease of installation and making sure that I have to do the job just once. Thanks for your advice and wisdom.

Dan
78 Eleganza
Allentown, NJ
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Re: [GMCnet] Sewer Valve Replacement [message #269456 is a reply to message #269444] Mon, 12 January 2015 10:49 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
Daniel DeLuca wrote on Mon, 12 January 2015 08:10
Hello,

My sewer valve leaks when it is being dumped, but otherwise is still watertight. I am putting replacing it on my "to-do" list. My coach appears to have the original Thetford valve. It seems that many people like to replace that valve with a more standard valve. Perhaps my google-fu is week, but I have not found instructions on how to do that. I have seen pictures, but I am wondering how difficult a job it is and what is needed. Since I am going to be doing this on my back, on gravel with everything a few inches above my head my primary concern is ease of installation and making sure that I have to do the job just once. Thanks for your advice and wisdom.

Dan

Dan,

Problem: The non-Thetford valves that are ridiculously in-expensive use a different bolt pattern. Some have used one original bolt hole and an adapter to make the old and new work. I have been trying to devise an adapter for some time now, but the first cut cost more than the Thetford valve to produce.

Is it leaking at the stem or the body joint? If it is the stem, it may be repairable. There is an O-ring there. If the stem has corroded. It is new valve time. (Unless you can get some friendly person with a lathe to make a new SS stem.)
There is a rebuild kit for the all plastic Thetford valves. If it is old enough to be stainless one side, there was no kit for that last time I looked. Thetford valves are available from the GMC parts suppliers and other old RV parts people. You can even older from Thetford, but they are as expensive as everybody else and much slower to ship than anybody else. (They would not let me stop in and pick it up on the way by.)

If the system is not currently the all plastic valve, then the frame immediately behind the valve will have to be cut to make room for the valve's pipe sleeve.

Good Luck

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: [GMCnet] Sewer Valve Replacement [message #269457 is a reply to message #269444] Mon, 12 January 2015 10:40 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
Messages: 7117
Registered: August 2005
Karma: 2
Senior Member
Read here
http://www.gmcmhphotos.com/photos/g3232-black-gate-valve-repair.html


On Monday, January 12, 2015, Daniel DeLuca wrote:

> Hello,
>
> My sewer valve leaks when it is being dumped, but otherwise is still
> watertight. I am putting replacing it on my “to-do” list. My coach
> appears to have the original Thetford valve. It seems that many people
> like to replace that valve with a more standard valve. Perhaps my
> google-fu is week, but I have not found instructions on how to do that. I
> have seen pictures, but I am wondering how difficult a job it is and what
> is needed. Since I am going to be doing this on my back, on gravel with
> everything a few inches above my head my primary concern is ease of
> installation and making sure that I have to do the job just once. Thanks
> for your advice and wisdom.
>
> Dan
> 78 Eleganza
> Allentown, NJ
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>


--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Re: [GMCnet] Sewer Valve Replacement [message #269476 is a reply to message #269456] Mon, 12 January 2015 12:26 Go to previous messageGo to next message
Daniel DeLuca is currently offline  Daniel DeLuca   United States
Messages: 120
Registered: June 2014
Karma: 0
Senior Member
Matt,

This kind of confirms my suspicion that it would not be worth doing an extensive modification. I think I will spend the $65.00 and be done with it.

Dan

> On Jan 12, 2015, at 11:49 AM, Matt Colie wrote:
>
> Daniel DeLuca wrote on Mon, 12 January 2015 08:10
>> Hello,
>>
>> My sewer valve leaks when it is being dumped, but otherwise is still watertight. I am putting replacing it on my "to-do" list. My coach appears
>> to have the original Thetford valve. It seems that many people like to replace that valve with a more standard valve. Perhaps my google-fu is
>> week, but I have not found instructions on how to do that. I have seen pictures, but I am wondering how difficult a job it is and what is needed.
>> Since I am going to be doing this on my back, on gravel with everything a few inches above my head my primary concern is ease of installation and
>> making sure that I have to do the job just once. Thanks for your advice and wisdom.
>>
>> Dan
>
> Dan,
>
> Problem: The non-Thetford valves that are ridiculously in-expensive use a different bolt pattern. Some have used one original bolt hole and an
> adapter to make the old and new work. I have been trying to devise an adapter for some time now, but the first cut cost more than the Thetford valve
> to produce.
>
> Is it leaking at the stem or the body joint? If it is the stem, it may be repairable. There is an O-ring there. If the stem has corroded. It is
> new valve time. (Unless you can get some friendly person with a lathe to make a new SS stem.)
> There is a rebuild kit for the all plastic Thetford valves. If it is old enough to be stainless one side, there was no kit for that last time I
> looked. Thetford valves are available from the GMC parts suppliers and other old RV parts people. You can even older from Thetford, but they are as
> expensive as everybody else and much slower to ship than anybody else. (They would not let me stop in and pick it up on the way by.)
>
> If the system is not currently the all plastic valve, then the frame immediately behind the valve will have to be cut to make room for the valve's
> pipe sleeve.
>
> Good Luck
>
> Matt
> --
> Matt & Mary Colie - Members GMCMI, GMCES
> '73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

Re: [GMCnet] Sewer Valve Replacement [message #269477 is a reply to message #269444] Mon, 12 January 2015 12:40 Go to previous messageGo to next message
Dennis S is currently offline  Dennis S   United States
Messages: 3046
Registered: November 2005
Karma: 2
Senior Member
Dan

Yes, installing a new Thetford valve is the easiest path forward. Use new stainless steel screws to install -- if the bottom two screws are stripped when you remove them, you can drill through and use bolts/nuts.

http://www.gmcmhphotos.com/photos/73-painted-desert-230/p34279-0084.html

Here is how Emery drilled through the bottom two holes.

http://www.gmcmhphotos.com/photos/electric-dump-valve-and-valtera-adapter/p3440.html

Dennis


Daniel DeLuca wrote on Mon, 12 January 2015 07:10
Hello,

My sewer valve leaks when it is being dumped, but otherwise is still watertight. I am putting replacing it on my "to-do" list. My coach appears to have the original Thetford valve. It seems that many people like to replace that valve with a more standard valve. Perhaps my google-fu is week, but I have not found instructions on how to do that. I have seen pictures, but I am wondering how difficult a job it is and what is needed. Since I am going to be doing this on my back, on gravel with everything a few inches above my head my primary concern is ease of installation and making sure that I have to do the job just once. Thanks for your advice and wisdom.

Dan
78 Eleganza
Allentown, NJ
_______________________________________________


Dennis S
73 Painted Desert 230
Memphis TN Metro
Re: [GMCnet] Sewer Valve Replacement [message #269595 is a reply to message #269477] Tue, 13 January 2015 13:39 Go to previous message
Wander Inn is currently offline  Wander Inn   United States
Messages: 100
Registered: January 2010
Location: Phoenix Az.
Karma: 0
Senior Member
DAN, I made a new stainless rod. I used a piece of 1/4" stainless steel round stock.
I hand filed the end to match the original rod. Drilled a hole at the end.

Mike


Mike & Chris Hughes 1977 Kingsley Phoenix, Az.
Previous Topic: [GMCnet] Latest Project - Water Tank and Bed
Next Topic: [GMCnet] Radiator Fan Woes
Goto Forum:
  


Current Time: Sat Nov 16 06:21:25 CST 2024

Total time taken to generate the page: 0.01287 seconds