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Black Tank Replacement [message #239170] Sat, 08 February 2014 08:11 Go to next message
mickey szilagyi is currently offline  mickey szilagyi   United States
Messages: 273
Registered: January 2013
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Senior Member
We have removed the single black tank system on our 77 Kingsley and have discovered too many cracks and issues to try and repair it. So, we're planning to replace it. We are also putting on a macerator while we're at it. Thanks to a bunch of you and your photos we have a pretty good plan on the macerator installation however we have some questions and would appreciate any help/suggestions you may offer.

We're trying to figure out the best way to establish the locations of the three holes we will have to drill in the top of the new tank. We need a 1.5, 2, and 3 inch. We're thinking of using the old tank as a template to make another template out of cardboard and make sure everything lines up properly.

We think we have the 3 inch toilet nipple pipe installation figured out - screw it into the new tank fitting and then hold the tank up to the bottom of the coach and screw the toilet flange until it rests on the shower floor and the screw holes line up with the holes through which the screws go to hold the flange to the plywood underneath.

We don't know how the other two tank drains attach to the respective drains that are protruding through the coach floor. The drains coming from above must go inside the drains coming up from the tank. But how do they seal or what is the trick to get them sealed? The PO made kind of a mess with the old setup. This is the part we really need help on.

And, how do we glue or attach the new fittings to the new tank once we have the holes drilled? Is there a special adhesive/caulk to do this? Do they screw into the tank or just set inside the new holes? We've read that ABS is difficult to glue to. Or do we just use the stuff that comes in a can that is used to attach two pieces of ABS pipe together?

Any think else about this installation you may wish to comment on please do...

Thank you all in advance for your input.


Mickey 1977 Kingsley, 403, Lansing, MI
Re: Black Tank Replacement [message #239177 is a reply to message #239170] Sat, 08 February 2014 09:10 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Registered: March 2007
Location: S.E. Michigan
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Senior Member
mickey szilagyi wrote on Sat, 08 February 2014 09:11

We have removed the single black tank system on our 77 Kingsley and have discovered too many cracks and issues to try and repair it. So, we're planning to replace it. We are also putting on a macerator while we're at it. Thanks to a bunch of you and your photos we have a pretty good plan on the macerator installation however we have some questions and would appreciate any help/suggestions you may offer.

We're trying to figure out the best way to establish the locations of the three holes we will have to drill in the top of the new tank. We need a 1.5, 2, and 3 inch. We're thinking of using the old tank as a template to make another template out of cardboard and make sure everything lines up properly.

We think we have the 3 inch toilet nipple pipe installation figured out - screw it into the new tank fitting and then hold the tank up to the bottom of the coach and screw the toilet flange until it rests on the shower floor and the screw holes line up with the holes through which the screws go to hold the flange to the plywood underneath.

We don't know how the other two tank drains attach to the respective drains that are protruding through the coach floor. The drains coming from above must go inside the drains coming up from the tank. But how do they seal or what is the trick to get them sealed? The PO made kind of a mess with the old setup. This is the part we really need help on.

And, how do we glue or attach the new fittings to the new tank once we have the holes drilled? Is there a special adhesive/caulk to do this? Do they screw into the tank or just set inside the new holes? We've read that ABS is difficult to glue to. Or do we just use the stuff that comes in a can that is used to attach two pieces of ABS pipe together?

Any think else about this installation you may wish to comment on please do...

Thank you all in advance for your input.

Mickey,

How many and what holes are in the new tank now??

You cannot glue anything to the tank material. I know what has been sold, but I have never seen it work on a black tank and the results of a failure .......

Go look for the new rubber sleeves that are used on modern RVs. These are much simpler and as least as secure in the long term for connecting to the black tank. Here is a link:
http://www.dyersonline.com/rv-plumbing/rv-holding-tanks/holding-tank-fittings.html
I am not suggesting that you buy from them, but that is the first link I could find. These parts are straight grommets and require no thread for connection. These will be great for the all connections.

Lay masking tape on the tank top and push it into place. The have someone on top mark where the holes want to be.

You will need big hole-saws, don't even try to cut the tank with a single point fly-cutter. You will get hurt.

ABS is not at all difficult to glue - if you have the correct adhesive. If you get the right can, you can even glue ABS to PVC. If you need any extra 3" ABS, I have some. If you recall, I am near DTW, but I won't be heading your way until June.

The reason RV people use ABS is that it is more rigid than PVC. That seems to be the only reason. So, of course, I needed that in the rework of my dump pipe, but I didn't 20'. I found 10' sections at a relatively near by Lowes (not all stock it) and I still have 5' left.

If you need to know any more about this, you have my number someplace. Call.

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] Black Tank Replacement [message #239181 is a reply to message #239170] Sat, 08 February 2014 09:34 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
Messages: 7117
Registered: August 2005
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Senior Member
this might help
http://gmcmotorhome.info/blacktnk.html#removal

gene



On Sat, Feb 8, 2014 at 6:11 AM, Mickey Szilagyi <mickey@apex-internet.com>wrote:

>
>
> We have removed the single black tank system on our 77 Kingsley and have
> discovered too many cracks and issues to try and repair it. So, we're
> planning to replace it. We are also putting on a macerator while we're at
> it. Thanks to a bunch of you and your photos we have a pretty good plan on
> the macerator installation however we have some questions and would
> appreciate any help/suggestions you may offer.
>
> We're trying to figure out the best way to establish the locations of the
> three holes we will have to drill in the top of the new tank. We need a
> 1.5, 2, and 3 inch. We're thinking of using the old tank as a template to
> make another template out of cardboard and make sure everything lines up
> properly.
>
> We think we have the 3 inch toilet nipple pipe installation figured out -
> screw it into the new tank fitting and then hold the tank up to the bottom
> of the coach and screw the toilet flange until it rests on the shower floor
> and the screw holes line up with the holes through which the screws go to
> hold the flange to the plywood underneath.
>
> We don't know how the other two tank drains attach to the respective
> drains that are protruding through the coach floor. The drains coming from
> above must go inside the drains coming up from the tank. But how do they
> seal or what is the trick to get them sealed? The PO made kind of a mess
> with the old setup. This is the part we really need help on.
>
> And, how do we glue or attach the new fittings to the new tank once we
> have the holes drilled? Is there a special adhesive/caulk to do this? Do
> they screw into the tank or just set inside the new holes? We've read that
> ABS is difficult to glue to. Or do we just use the stuff that comes in a
> can that is used to attach two pieces of ABS pipe together?
>
> Any think else about this installation you may wish to comment on please
> do...
>
> Thank you all in advance for your input.
> --
> Mickey
> 1977 Kingsley, 403, Lansing, MI
> _______________________________________________
> 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
-------
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Re: Black Tank Replacement [message #239189 is a reply to message #239170] Sat, 08 February 2014 10:49 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
Messages: 7111
Registered: November 2004
Location: Dexter, Mo.
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Senior Member
I have read your remarks a couple of times but don't understand why you need three new holes in the new tank. I guess it really is not my Buisness. But, I would run through all of the pictures on the photo site and follow the link that gene posted before cutting it.
Good luck,
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] Black Tank Replacement [message #239194 is a reply to message #239189] Sat, 08 February 2014 11:17 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Registered: May 2010
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Senior Member
Mickey, AFAIK, original waste tanks are no longer available. When you buy a
replacement tank, it will come with a drain opening only. You must custom
fit it to your coach, and make penetrations to fit your application. The
most common way of doing that is by using special grommets that fit holes
that you make with hole saws. No adhesive is needed. To be sure, exact
placement in the new tank is critical to success. Nearly every OEM tank
that I have replaced that were either spun welded or adhesive mounted
inlets were cracked and leaking. The grommets absorb vibration, are quite
forgiving when it comes to expansion and contraction of the tank and
piping. The first couple that I did, I had reservations about. but they
hold up well, and when you need to lower the tank for service to drains and
the like, they are a lot easier to work with. There is more than one source
for the tanks, but Jim K has at least 4 tanks available that cover most all
applications to GMC upfitted coaches. Royale and Birchavens that were
upfitted by Coachman Industries are another matter. They are all different.
I have seen them fitted with one, two, and three different tanks, with all
manner of drains. What I do when I service tanks, is to remove all drain
piping and tanks, lay them all out in the driveway, and photograph the
individial pieces. That way when time comes to put it back together, you
can have kind of a blueprint on how it once fit. Others have done it by
their own methods and it works for them as well. Plumbers only need to know
two important things. Payday comes on Friday, and Crap don't run uphill.
(grin) If I can help further, be sure to ask.
Jim Hupy
Salem, OR
78 GMC Royale 403


On Sat, Feb 8, 2014 at 8:49 AM, Dan Gregg <gregg_dan@hotmail.com> wrote:

>
>
> I have read your remarks a couple of times but don't understand why you
> need three new holes in the new tank. I guess it really is not my Buisness.
> But, I would run through all of the pictures on the photo site and follow
> the link that gene posted before cutting it.
> Good luck,
> Dan
> --
> Dan & Teri Gregg
> Dexter, Mo.
>
> http://danandteri.blogspot.com/
>
>
>
>
> _______________________________________________
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>
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Re: Black Tank Replacement [message #239197 is a reply to message #239170] Sat, 08 February 2014 12:09 Go to previous messageGo to next message
mickey szilagyi is currently offline  mickey szilagyi   United States
Messages: 273
Registered: January 2013
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Senior Member
Thanks to everyone for your comments about the black tank.

Matt, thanks for the info on the rubber inlet grommets. So, are they used to go between the MH flooring down to the tank? Are they a coupler, like a slip coupler or does one piece of drain pipe just run through them like say a grommet for electrical wires would work? Are the grommets also used instead of threaded tank fittings?

I looked at the link Gene referenced and it sounds like we should be able to access the plumbing from above. I didn't think that was possible with the removal of a bunch of stuff. Matt, you referenced holding the tank up and having someone mark it from above. Same question - we didn't think we could "see" the tank through the two sink/shower drains.

Dan, our bad tank has 3 fittings on the top. There is a 1.5 inch threaded fitting that connects to the kitchen sink drain on the port side of the coach. There's a 2 inch threaded fitting that connects to the bathroom sink and shower drain on the starboard side of the coach. And there's the 3 inch toilet drain which we have access to from both above and below. We were assuming we would drill out new holes on the new tank to correspond to the existing drains coming from above. Again, are you saying NOT to use threaded fittings on the tank but use the rubber grommets instead? And, if so, do we glue pieces on the existing pipes that come through the floor making them just long enough to go into the tank once it's pushed up in place, no glue or caulk needed? You're saying the grommets won't leak? And, yes, the toilet threaded fitting on the tank has a crack in it, one of the many cracks in the tank. Each of the sink drains protrude down about 1 inch below the floor plywood. From underneath they are still up inside small openings and as is will not reach the new tank.

We are considering buying the new tank from Cinnabar as they are only about 2 hours away and we can save on shipping. They say their tank only has the main outlet at the back of the tank and the sending unit hole also at the back of the tank. All other holes need to be drilled.

Another thing we need to deal with is there is a 5-6 inch in diameter lump protruding down about 3/4-1 inch below the underside of the coach. It is the shower/bath sink trap. The old tank has a depression in it that accomodates that bulge. We doubt if the new tank will have the same depression but we will see.

Adhesive for polypropylene and polyethylene - we did a lot of looking for something that is supposed to adhere to the two plastics. We found 3M Scotch Weld 4693 and 4693H. 4693 comes in two parts and must be mixed - it is runny. 4693H comes in a tube and is thicker. We haven't tried either of them yet. Here's a link for the 4693H:

http://www.shop3m.com/3m-scotch-weld-high-performance-industrial-plastic-adhesive-4693h-clear-5-oz-tube.html

Anyone try either of these?

Sorry for the long windedness, but I don't know how else to say it all. We really appreciate the help and hope to do this only once, right the first time.

My son, Chris, has pictures of the old tank and I'll get him to add them to our photo album.

Thanks everyone.


Mickey 1977 Kingsley, 403, Lansing, MI
Re: Black Tank Replacement [message #239198 is a reply to message #239197] Sat, 08 February 2014 12:27 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
Messages: 7111
Registered: November 2004
Location: Dexter, Mo.
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Senior Member
Oh, ok. I thought they came with the holes for the pipes already in the tank. That is what had me confused. These guys will steer you right. I would still search the photo site before taking this project on.
I'd also call Matt for assistance.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] Black Tank Replacement [message #239199 is a reply to message #239198] Sat, 08 February 2014 12:59 Go to previous messageGo to next message
Bruce Hart is currently offline  Bruce Hart   United States
Messages: 1501
Registered: October 2011
Location: La Grange, Wyoming
Karma: 5
Senior Member
Just a thought. Since your old black tank is no good, could you cut the
top off and use it as a pattern to locate the holes on top of the new
tank. It might not be the clleanest of jobs but it should get the holes in
the right location.

On Sat, Feb 8, 2014 at 11:27 AM, Dan Gregg <gregg_dan@hotmail.com> wrote:

>
>
> Oh, ok. I thought they came with the holes for the pipes already in the
> tank. That is what had me confused. These guys will steer you right. I
> would still search the photo site before taking this project on.
> I'd also call Matt for assistance.
> Dan
> --
> Dan & Teri Gregg
> Dexter, Mo.
>
> http://danandteri.blogspot.com/
>
>
>
>
> _______________________________________________
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> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Bruce Hart
1976 Palm Beach
Milliken, Co
GMC=Got More Class
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Bruce Hart 1976 Palm Beach 1977 28' Kingsley La Grange, Wyoming
Re: [GMCnet] Black Tank Replacement [message #239200 is a reply to message #239199] Sat, 08 February 2014 13:20 Go to previous messageGo to next message
mickey szilagyi is currently offline  mickey szilagyi   United States
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Registered: January 2013
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Senior Member
Bruce, yes, thanks for suggesting that. We've thought about that a little already. We're really concerned about getting the holes just right as we don't think there's any wiggle room. We still don't understand how we should attach the pipes coming up out of the tank, whether to use the rubber grommets or to put in threaded fittings and then ABS nipple fittings into those. Then we must have them lined up to match the drains coming down from above and we don't yet understand how the pipes on the tank attach to the pipes coming down. For flow purposes the ones coming down through the coach floor should either attach to or slip inside the pipes going into the tank.

Thanks for your input.


Mickey 1977 Kingsley, 403, Lansing, MI
Re: [GMCnet] Black Tank Replacement [message #239201 is a reply to message #239194] Sat, 08 February 2014 13:26 Go to previous messageGo to next message
mickey szilagyi is currently offline  mickey szilagyi   United States
Messages: 273
Registered: January 2013
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Senior Member
Jim,

So you are saying to use the rubber grommets as the fittings that go in the top of the tank. They will seal around the ABS pipe that slips into them and they won't leak? Do you use any sealant or adhesive to hold them in place? Do you use anything on the pipes as a back up seal when sliding the pipes into the grommets?

Thanks!


Mickey 1977 Kingsley, 403, Lansing, MI
Re: [GMCnet] Black Tank Replacement [message #239202 is a reply to message #239201] Sat, 08 February 2014 13:54 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Registered: May 2010
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Senior Member
Mickey, the pipes fit into the grommets after the grommets are installed
into the holes you cut. The grommets are fairly low durometer neoprene. It
is a wrestling match to install them because they fit the holes exactly.
Once in place, you lube the inside of the grommets with silicone grease and
then push and twist the pvc pipe into the grommets. I have also used a
special lubricant made for brake rubber parts that works well. If you
choose, a pvc union can be glued into a short piece of pvc pipe that
penetrates the grommets. If you have access from above to assemble the
union, that makes for an easier install. Many times there is not enough
room, so a glued coupling has to be used. For the toilet flange, I usually
use a long threaded 3" flush mount flange that finishes at floor height.
You can place a straight edge across the floor and with the tank and
grommets in place, measure from the inside of the grommets to the bottom of
the straight edge for your length of pipe. I have not had any leaks using
grommets. They really fit tightly. The threaded toilet flange can be
adjusted so that it exactly matches the floor. I use a good sealant on the
floor to flange joint, and turn the mounting ring so it matches the toilet
base hold down bolts. This works for me. Go slowly and deliberately.
Measure carefully and save the brew until after you check fo leaks. I will
try to send you some pictures.
Jim Hupy
Salem, Or
78 GMC Royale 403
On Feb 8, 2014 11:26 AM, "Mickey Szilagyi" <mickey@apex-internet.com> wrote:

>
>
> Jim,
>
> So you are saying to use the rubber grommets as the fittings that go in
> the top of the tank. They will seal around the ABS pipe that slips into
> them and they won't leak? Do you use any sealant or adhesive to hold them
> in place? Do you use anything on the pipes as a back up seal when sliding
> the pipes into the grommets?
>
> Thanks!
> --
> Mickey
> 1977 Kingsley, 403, Lansing, MI
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>
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Re: [GMCnet] Black Tank Replacement [message #239205 is a reply to message #239202] Sat, 08 February 2014 14:29 Go to previous messageGo to next message
mickey szilagyi is currently offline  mickey szilagyi   United States
Messages: 273
Registered: January 2013
Karma: 0
Senior Member
Jim, this is extremely helpful. I'm beginning to understand how this should work. If at all possible pictures would be great.

I understand the grommets being placed in the tank top. They fit and stay put without any adhesive or caulk. Are you saying by putting a union on the pipe that penetrates the grommet the union will keep the pipe from slipping further into the grommet as the only part of the pipe going into the top of the tank is what is sticking past the union?

Are all the pipes glued or fixed in place to the plumbing coming through the floor before they are pressed through the grommets? This seems to make the most sense. If so, then they are fixed and the tank is pressed up as the grommets are penetrated. Or are the pipes that go through the grommets placed through the grommets before the tank is lifted into place thus attaching to the plumbing above, but then how would you fix the pipes to the existing plumbing above?

We've noticed that the OD of ABS and PVC is not quite the same. Which one have you used to go through the grommets? With the appropriate adhesive we can glue ABS and PVC together.

The 3 inch pipe from the toilet flange goes down and through after the tank is in place as we have access from the top. For the other two drains that go into the tank so far I don't think we have access from inside the coach to work on those pipes so that will have to be done from underneath.

Thanks again for your help. This is making a lot more sense than when we started.



Mickey 1977 Kingsley, 403, Lansing, MI
Re: Black Tank Replacement [message #239206 is a reply to message #239197] Sat, 08 February 2014 14:43 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
mickey szilagyi wrote on Sat, 08 February 2014 13:09

Thanks to everyone for your comments about the black tank.

Matt, thanks for the info on the rubber inlet grommets. So, are they used to go between the MH flooring down to the tank? Are they a coupler, like a slip coupler or does one piece of drain pipe just run through them like say a grommet for electrical wires would work? Are the grommets also used instead of threaded tank fittings?

I looked at the link Gene referenced and it sounds like we should be able to access the plumbing from above. I didn't think that was possible with the removal of a bunch of stuff. Matt, you referenced holding the tank up and having someone mark it from above. Same question - we didn't think we could "see" the tank through the two sink/shower drains.

Dan, our bad tank has 3 fittings on the top. There is a 1.5 inch threaded fitting that connects to the kitchen sink drain on the port side of the coach. There's a 2 inch threaded fitting that connects to the bathroom sink and shower drain on the starboard side of the coach. And there's the 3 inch toilet drain which we have access to from both above and below. We were assuming we would drill out new holes on the new tank to correspond to the existing drains coming from above. Again, are you saying NOT to use threaded fittings on the tank but use the rubber grommets instead? And, if so, do we glue pieces on the existing pipes that come through the floor making them just long enough to go into the tank once it's pushed up in place, no glue or caulk needed? You're saying the grommets won't leak? And, yes, the toilet threaded fitting on the tank has a crack in it, one of the many cracks in the tank. Each of the sink drains protrude down about 1 inch below the floor plywood. From underneath they are still up inside small openings and as is will not reach the new tank.

We are considering buying the new tank from Cinnabar as they are only about 2 hours away and we can save on shipping. They say their tank only has the main outlet at the back of the tank and the sending unit hole also at the back of the tank. All other holes need to be drilled.

Another thing we need to deal with is there is a 5-6 inch in diameter lump protruding down about 3/4-1 inch below the underside of the coach. It is the shower/bath sink trap. The old tank has a depression in it that accomodates that bulge. We doubt if the new tank will have the same depression but we will see.

Adhesive for polypropylene and polyethylene - we did a lot of looking for something that is supposed to adhere to the two plastics. We found 3M Scotch Weld 4693 and 4693H. 4693 comes in two parts and must be mixed - it is runny. 4693H comes in a tube and is thicker. We haven't tried either of them yet. Here's a link for the 4693H:

http://www.shop3m.com/3m-scotch-weld-high-performance-industrial-plastic-adhesive-4693h-clear-5-oz-tube.html

Anyone try either of these?

Sorry for the long windedness, but I don't know how else to say it all. We really appreciate the help and hope to do this only once, right the first time.

My son, Chris, has pictures of the old tank and I'll get him to add them to our photo album.

Thanks everyone.

Mickey,
I guarantee you will not like what I have to tell you, but believe me (who has had his black tank three times), you really need to take more apart to do this job right. Well, the option to do it twice is always available. I don't suggest that.

If you got the tank down without unscrewing things, then there is stuff that is already screwed up there. Two things you and Chris need to do. If you don't do this, the reinstallation will be a nightmare of significant magnitude.
- First, take out the potable water tank. Be careful with it. You will see the fill on the top and the level sensor. Both need to be disconnected. You cannot access the draw fitting. it is underneath and outboard. You can remove the suction line from the potable pump and hopefully budge the tank aft enough to get at the vent connection on the forward inboard upper corner. Pull the tank out. (Lots of luck finding someplace to put it.) and you will see the shower and sink drain/vent connection from the top.
- Second dive into the closet and start taking things apart. Someplace in the back corner there should be a piece you can remove that will expose the galley drain as it comes down over the wheel well.

My shower and galley drains were connected with iron pipe. That was the real problem from the get-go. It appears they first corroded and cracked the tank fittings and then rotted away completely. You can decide how you will do the repair when you get there.

To answer your other question, Yes, the grommets that I gave you the link to (by the way, shop the web for those, prices vary) get installed in the tank top skin and the carefully beveled attaching drain "slips" in. (Slips in My Ass - with a coat of ArmorAll and a couple of screw drivers all supplanted by copious amounts of profanities, it will go in.)

You may have to repair the exiting drains and extend them enough to go well into the rubber bushing. This is probably easiest to do by making up new drain connections and attaching them to the existing drains with rubber couplings. Another memory fired... If you are going to try to put the tank up to intact drains (no rubber couplings) cut the end of the drain where it goes into the tank at about a 10~15° angle. This is so you don't have to try to get the entire edge engaged at the same time. it still will need a bevel.

The best part about using the grommets is that nothing will have to get welded to the tank. The pipe from the pot will not have to be screwed in. It will just go in the way the others did.

I have never had any experience with the adhesive you linked to, but I would be leery. Its base solvents are cyclohexane (I hope they just mis-spelled it) and acetone and it will not actually chemically bond to PE and PP. Its adhesion to PP is pretty good even still. It is not a two part adhesive.

As said, call me if you need/want.

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] Black Tank Replacement [message #239207 is a reply to message #239205] Sat, 08 February 2014 14:53 Go to previous messageGo to next message
hal kading is currently offline  hal kading   United States
Messages: 642
Registered: February 2004
Location: Las Cruces NM
Karma: 4
Senior Member
Mickey,

Is your Kingsley a rear twin bed model? If so I don't remember the drain layout. If it is the more common passenger side bath you can access the kitchen sink drain in the air compressor cabinet. It is under the sloped area at the aft end of the cabinet. The passenger side drain is accessed at the front end of the fresh water tank compartment under the pass side settee.

Check with Jim K for a new tank. I believe he has them with the connections already fitted.

Hal Kading 78 Buskirk Las Cruces NM
Re: [GMCnet] Black Tank Replacement [message #239208 is a reply to message #239205] Sat, 08 February 2014 14:51 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Mickey, No, there is a lip on the inside of the grommet near the bottom of
it. The schedule 40 black pvc pipe "JUST FITS" the inside of the grommet
and projects into it until it encounters the lip. The union allows you to
leave the pipe inserted into the grommet and the tank placed under the
coach into final position. This will allow, IF ACCESS IS THERE, you to
connect the old existing plumbing to the new tank fittings. If you do not
have access, then you will use glued couplings to connect as the tank is
put in place. Easier in practice than it is to explain it. Someone once
told me that hindsight is always 20/20. Lots to be said for experience.
Send me a PM so I have your email address and I will try to send you some
pictures.
Jim Hupy
Salem, Or
78 GMC Royale 403
On Feb 8, 2014 12:29 PM, "Mickey Szilagyi" <mickey@apex-internet.com> wrote:

>
>
> Jim, this is extremely helpful. I'm beginning to understand how this
> should work. If at all possible pictures would be great.
>
> I understand the grommets being placed in the tank top. They fit and stay
> put without any adhesive or caulk. Are you saying by putting a union on
> the pipe that penetrates the grommet the union will keep the pipe from
> slipping further into the grommet as the only part of the pipe going into
> the top of the tank is what is sticking past the union?
>
> Are all the pipes glued or fixed in place to the plumbing coming through
> the floor before they are pressed through the grommets? This seems to make
> the most sense. If so, then they are fixed and the tank is pressed up as
> the grommets are penetrated. Or are the pipes that go through the grommets
> placed through the grommets before the tank is lifted into place thus
> attaching to the plumbing above, but then how would you fix the pipes to
> the existing plumbing above?
>
> We've noticed that the OD of ABS and PVC is not quite the same. Which one
> have you used to go through the grommets? With the appropriate adhesive we
> can glue ABS and PVC together.
>
> The 3 inch pipe from the toilet flange goes down and through after the
> tank is in place as we have access from the top. For the other two drains
> that go into the tank so far I don't think we have access from inside the
> coach to work on those pipes so that will have to be done from underneath.
>
> Thanks again for your help. This is making a lot more sense than when we
> started.
>
>
> --
> Mickey
> 1977 Kingsley, 403, Lansing, MI
> _______________________________________________
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>
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Re: [GMCnet] Black Tank Replacement [message #239215 is a reply to message #239205] Sat, 08 February 2014 15:45 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
If you contact the manuf. and tell him your gmc model. They will spin-in the fittings in the wright places. No o-nrings needed.

FREE WIFI @ Mickey D





On Feb 8, 2014, at 12:29 PM, Mickey Szilagyi <mickey@apex-internet.com> wrote:

>
>
> Jim, this is extremely helpful. I'm beginning to understand how this should work. If at all possible pictures would be great.
>
> I understand the grommets being placed in the tank top. They fit and stay put without any adhesive or caulk. Are you saying by putting a union on the pipe that penetrates the grommet the union will keep the pipe from slipping further into the grommet as the only part of the pipe going into the top of the tank is what is sticking past the union?
>
> Are all the pipes glued or fixed in place to the plumbing coming through the floor before they are pressed through the grommets? This seems to make the most sense. If so, then they are fixed and the tank is pressed up as the grommets are penetrated. Or are the pipes that go through the grommets placed through the grommets before the tank is lifted into place thus attaching to the plumbing above, but then how would you fix the pipes to the existing plumbing above?
>
> We've noticed that the OD of ABS and PVC is not quite the same. Which one have you used to go through the grommets? With the appropriate adhesive we can glue ABS and PVC together.
>
> The 3 inch pipe from the toilet flange goes down and through after the tank is in place as we have access from the top. For the other two drains that go into the tank so far I don't think we have access from inside the coach to work on those pipes so that will have to be done from underneath.
>
> Thanks again for your help. This is making a lot more sense than when we started.
>
>
> --
> Mickey
> 1977 Kingsley, 403, Lansing, MI
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
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Re: [GMCnet] Black Tank Replacement [message #239218 is a reply to message #239215] Sat, 08 February 2014 16:35 Go to previous messageGo to next message
rjw   United States
Messages: 697
Registered: September 2005
Karma: 4
Senior Member
I don't know if this has already been mentioned because I don't read all of the posts and look at all the links.

More than ten years ago I had Cinnabar replace my black tank because the original tank was leaking when full. We found out that it was leaking because there was a crack in the top.

The way they approached locating the holes for the pipes was to put grease on the pipes. They put the tank in position and the grease marked the places where they used appropriate sized hole saws to cut the tank. They then used used rubber grommets to seal the pipes to the tank. I was skeptical at the time that the grommets would seal, but after all this time I have no leaks.

They had to do the job twice, because the first tank they installed leaked at the fitting for the dump outlet. I was vert happy that they did the job twice at no extra cost to me. If it had been me doing the job I would have been annoyed if I had to do it twice. They guys that did it were annoyed because they had to stay late so i could get home that night.


Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com

Roller Cam 455, TBI+EBL, 3.42 FD, 4 Bag, Macerator, Lenzi (brakes, vacuum system, front end stuff), Manny Tranny, vacuum step, Tankless + OEM water heaters.
Re: [GMCnet] Black Tank Replacement [message #239276 is a reply to message #239208] Sun, 09 February 2014 09:34 Go to previous messageGo to next message
mickey szilagyi is currently offline  mickey szilagyi   United States
Messages: 273
Registered: January 2013
Karma: 0
Senior Member
Jim and everyone else.

Jim, I tried to send you a PM. Don't know if I'm doing it right but when I tried to send it it says you aren't accepting PMs.

We have read all the posts and are starting to buy all the parts, the tank, fittings and so forth. Everyone has been extremely helpful and we believe we have a workable plan in place to replace the black tank. We will post results if/when it works or not in hopes it will help someone else in the future. We will be doing this as soon as we get a little warmer weather. We're working in a barn but without heat.

We will be installing a macerator once the tank is in place and have a plan for that too. What type of hose is used as the discharge hose out of the macerator and where can we get it? Right now our plan is to use spa hose - Watts 1 inch ID PVC Spa Flex Hose that we can get through Home Depot, 50 ft for $50. We don't know how flexible it is until we get it. If this isn't a good idea or something else is better please let us know.

Again, thanks to everyone for your input. Another weekend project that will take us all spring.


Mickey 1977 Kingsley, 403, Lansing, MI

[Updated on: Sun, 09 February 2014 09:36]

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Re: [GMCnet] Black Tank Replacement [message #239292 is a reply to message #239276] Sun, 09 February 2014 11:20 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
mickey szilagyi wrote on Sun, 09 February 2014 09:34

Jim and everyone else.

Jim, I tried to send you a PM. Don't know if I'm doing it right but when I tried to send it it says you aren't accepting PMs.

We have read all the posts and are starting to buy all the parts, the tank, fittings and so forth. Everyone has been extremely helpful and we believe we have a workable plan in place to replace the black tank. We will post results if/when it works or not in hopes it will help someone else in the future. We will be doing this as soon as we get a little warmer weather. We're working in a barn but without heat.

We will be installing a macerator once the tank is in place and have a plan for that too. What type of hose is used as the discharge hose out of the macerator and where can we get it? Right now our plan is to use spa hose - Watts 1 inch ID PVC Spa Flex Hose that we can get through Home Depot, 50 ft for $50. We don't know how flexible it is until we get it. If this isn't a good idea or something else is better please let us know.

Again, thanks to everyone for your input. Another weekend project that will take us all spring.



Mickey

Unless you just want 50 feet of hose, consider looking in the garden section for 20 ft of pond hose. Lowes has Tetra for about $21 for the 20 ft of 1 inch id.

Dennis


Dennis S
73 Painted Desert 230
Memphis TN Metro

[Updated on: Sun, 09 February 2014 11:27]

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Re: [GMCnet] Black Tank Replacement [message #239293 is a reply to message #239292] Sun, 09 February 2014 11:27 Go to previous messageGo to previous message
WD0AFQ is currently offline  WD0AFQ   United States
Messages: 7111
Registered: November 2004
Location: Dexter, Mo.
Karma: 207
Senior Member
Mickey, I pitched my one nice and replaced it with 3/4". I also have a 10 foot extension that is 1/2 ". 3/4 is so much easier to deal with but many like the 1 ". I buy mine by the foot at any local hardware store when I need it. Cheap. I also use clear hose. Some don't like that much. Very Happy
Good luck with your complete install. Check the photo site if you have problems.
Dan


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