GREY TANK LEAK... HELP - Montana Owners Club

mvg · 01-13-2008, 08:25 AM

My grey tank leaks from the belly, but only when it is almost full. I have read elsewhere that the problem is probably a crack at the location where the pipe enters the tank. Is the best access for the fix really from the underbelly, or is there a way to it from inside the storage area. I don't look forward to being under the rig for a fullday, arthitis and all. Any advice, comments, pictures would be appreciated.

OntMont · 01-13-2008, 10:19 AM

Mine has also developed this problem. It leaks if I let it get completely full. For the time being, I am just going to avoid letting it get full. Some nice day in the summer, I may take a closer look at it. I suspect, but have not confirmed, that the leak is at the drain pipe connection to the tank, it may just need re-sealing. I have heard that installing one of those rubber connection sleeves (coupling) will help prevent this by providing some flexibility to the plumbing. Interested to see what others have found and done.

mvg · 01-13-2008, 10:58 AM

That's what I'm thinking of doing, but what is the easiest way to get at it ? Underbelly or through the floor of the storage area ?

OntMont · 01-13-2008, 12:31 PM

It would depend on your model, and where the plumbing is routed. I think I can get at mine by cutting a larger opening in the bottom of the cabinet where the drain is routed. This is under the "garbage" drawer in ours, so it won't show and is fairly easy to get at.

mvg · 01-13-2008, 12:48 PM

So true, depends on model and year of course. DUH on me.

My rig is a mountaineer 2006, 298RLS. Thanks.

RRman · 01-14-2008, 09:27 AM

The Payne's (RV-dreams.com) 05 Cambridge developed a grey tank leak. Had to open up the belly and remove to reveal a small crack in the top. Fortunately for them covered under warranty. As I have an 05, I hope this was a random/fulltime use occurrence and not a syndrome like Dometic Refrigerator failures.

snfexpress · 01-14-2008, 11:47 AM

On our 3400, it is the galley tank that is leaking. It doesn't appear to be the inlet connection. I am having the tank removed in the next few days, so will take pictures and post results.

From what I learned at the factory, the preferred way to remove the tanks is from underneath. The rail perpindicular to the fore-aft axis of the 5er is meant to be removed, thereby permitting the offending tank to be moved around to get it to drop down (after plumbing intake has been either cut or removed).

We'll see if the above description is accurate.

HamRad · 01-14-2008, 12:07 PM

Mike,

Don't forget the vent pipe connection.

We just applied another radiator repair kit on our gray tank outlet pipe. I'm hoping that stops the leak.

HamRad

snfexpress · 01-14-2008, 12:20 PM

Good point, Dennis. On our 3400 the sink drain and vent pipe Y, then enter the inlet to the tank.

gkbutler · 01-14-2008, 11:44 PM

We developed a leak on our grey tank about six months after we bought it. Like the others, it only happened when the tank was almost full. I applied various compounds that were supposed to stop leaks and had no luck what so ever. Fortunately our tank was covered under warranty. We kept the grey tank open all winter. It was easier to do this rather than keep pulling the belly off to dry out.

wersqu · 01-15-2008, 02:20 PM

Our Grey water tank started leaking this past October for the first time. We have an extended warranty that covered most of the repair. This required removing the belly etc. Our dealership stated the tank was leaking in one of it's corners. It was wavy and very thin and brittle at this point. They stand behind it being a defective tank right from the start. The only disappointing part of the experience (other than the leak to begin with) is we had to pay over $100.00 to ship the tank from the factory to our dealership. We expected to only have to pay our deductible. Looking at the number of responses that have had leaks it makes you wonder if there isn't more going on with these tanks.

carlson · 01-16-2008, 05:11 PM

The tanks are supported by two long metal angle irons that are attached to the frame, one is welded in and the other is held in place with metal screws.
What is happening is that when the tank fills up, because of the weight of the water, a little over 8 lbs per gallon the tanks expand out and where there maybe a weakness in the plastic, it will blow a hole.
Then it leaks when the weight builts up in the tank.
I patched and put fiberglass patch on my galley tank and whn it get full, it still leaks.
Will get it replaced in the spring.

mvg · 01-22-2008, 03:59 PM

Well....I went under the beast, peeled away its skin and found the leaky innards. It was a pin hole so small it would only start oozing when the tank was half full, and then did a mankanpiss imitation when the tank was full. The hole was so tiny, I couldn't even put a push pin in it to mark the hole.

I JD Welded it, let it dry and cure and then applied a liberal dose of duct tape. Should work. We'll see. Thanks to all for the advice, tips, and encouragement.

mvg · 02-07-2008, 10:20 AM

Wellllll...., it didn't hold. I'm getting the tank replaced. Got a great price for the tank from Gooding RV in Mission and found someone to come and do the replacement at my site. The whole thing will prbably cost less than $300.

Dogman · 02-08-2008, 02:06 PM

Some info I'd like to pass along. We just had our kitchen tank replaced by the dealer. It started leaking about a week ago and I called a couple of RV repair places but they both said that it was an in shop job. I called the dealer we bought the trailer from and set up an appointment. We got there early in the morning and they got right on it. After about 2 hours they came and told us it was leaking right where the drain entered the tank and that the tank was split and needed to be replaced. What a nightmare!!! Now the rest of the story.
They said the new tank was about $ 80.00 but it would take a week to get it unless we wanted to pay for 2nd day air ($ 125). We paid the extra. Then they told us it would be about a 12 to 14 hour job ( at $ 96 per hour!) Having not much choice at that point we gave them the go ahead. They have a hookup area on site so they told us we could stay there until the tank came in. It was over a weekend so we were there for 4 days. I watched them do the job. My advice is don't attempt it yourself. It did in fact take 12 hours and it was not fun (this is a large dealership thats been in business for 40 years). Very difficult to get at and not one fitting that could be taken apart. They had to cut the pipes to drop the tank and due to the tight spaces had to do it with a hand held hack saw blade. The new tank was installed and then all the plumbing had to be refitted. They even had to pull the converter from the wall because one of the pipes was routed through the wall behind the converter. Buttoning up the belly was another challenge. Total cost $ 1596.00. Total parts and supplies including the new tank was $ 254.00. The rest was labor.
I'm sure many of you can find a cheaper labor rate but in any case think twice about looking at it as a DIY job unless you've got some help, a lot of patience, and have a good idea about what your doing.

mvg · 02-09-2008, 03:06 AM

I had my galley tank replacd last week. It was the low cost of the replacement that convinced me to replace the grey tank I patched up. The galley tank replacement cost me $200 labour, $25 parts, $92 for the tank. I expect the grey tank replacement to cost le less. Mind you, I did remove the underbelly cover myself and that took me 45 minutes. My installer had a helper included in the $60 per hour. I realize things in the RGV are cheaper, but $1596 smells like a rip-off to me.

Waynem · 02-09-2008, 03:12 AM

I found some of that "Mighty Putty," in Wally-world. That's the one they show on TV commercials. It's a green stick with a with core middle. You cut what you want and knead it together. It is supposed to work with water. I don't think the JB weld will work with a wet area. Mighty Putty is worth a try. $19.95 a package.

richfaa · 02-09-2008, 03:17 AM

Which is why we spent the bucks for the extended warranty. 1596.00 is more than the cost of our Extended Warrenty (The shield)

scductman · 02-10-2008, 11:15 AM

Guys as some of you know I just repaired my front galley tank. my dealer wanted 175$ for the tank an 10hrs labor @ 90$ to put it in. It is alot of work an you have to rework the pipes but I could not see paying that much for something I could do myself since I dont fultime. you can cut a bigger hole in the floor to see the top of the tank but be carful the top of the tank is flat up to floor on mine. hope this helps. bobby

mvg · 02-13-2008, 02:53 AM

Yesterday, we replaced our grey tank. The repair guy showed up, but without his helper. No problema, I'm a good helper. I had taken out the underbelly cover: 15 minutes. We replaced the tank in 2.5 hours, including a 20 minute trip we took together to the hardware store to find some plumbing parts. My total cost is: $95 for the tank, $8 for parts, $150 labbour. Total: $252. I have a 2006 298RLS.

Thought I'd provide this info to help you judge what a job like this is worth.

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