re: re: Gray Water Tank Broke - Montana Owners Club

jackandh2o · 01-04-2010, 03:00 AM

Picked up the rig on Thursday, they replaced the gray water tank. I had been there before when they did the Dometic recall and I had a hydraulic leak and they tightened some fittings the the slides still crept open. They were checking it out and the ram that pushes the big slide was leaking.They also replaced the ram and hopefully no more creeping slides. Thank you extended warranty. We are staying in our daughters driveway in Hemet right now and will be leaving for Kernville Ca. on Thursday for a 5 night stay. That should be a good test of both items. I finally got around to doing some tests on the tank. I filled a 5 gal bucket and poured it into the shower. I almost had 20 gallons in it and no leak, then it started. So I figured it was getting into the tank OK and my problem was the tank. It is in Bullhead AZ. getting replaced. It should be covered by my extended warranty.

Thanks again for all the input.

Ray

On our last trip out over Christmas and New Years we stayed in our daughters driveway and then went to a campground for a few days of R and R and tank emptying. It was raining so I got us all set up minus dumping the tanks. The next morning DW took her shower and then I took mine. Th tank was full and i was standing in water when finished. Got dressed and was heading out to drain the tanks when I heard a draining sound and noticed the shower was empty. Like a dummy I stood there for a few seconds thinking there had been an air bubble and the the shower drained into the tank.I smiled to myself all happy and went outside to drain the tanks and realized it was draining itself. I quickly hooked up the hose and drained the balance of the tank.

At first I was thinking that the fitting where the shower meets the tank let go, But with my luck the tank probably ruptured.

Does this sound familiar to any of you and is it a major repair?

Thanks
Ray

Army Guy · 01-04-2010, 03:12 AM

Not sure on yours but we had to remove the belly to get to the tank. It is possible that with all the weight of the water, the neck at the top of the tank cracked. Hard to say until you get up in there and look. Good luck.

richfaa · 01-04-2010, 03:32 AM

?? " it was draining itself"?? does that mean it was draining via the drain valve?? or from the underbelly??

jackandh2o · 01-04-2010, 05:43 AM

When I set up I thought I was level but I was a little low on the door side. All the water was coming out right under the storage compartment(the underbelly) on the passenger side. I have never messed with those panels, but I'm hoping all you need is an electric screwdriver and patience.

Ray

richfaa · 01-04-2010, 08:52 AM

Water in the underbelly = leak.Have no idea were the grey tank is on your unit but " electric screwdriver and patience."

will do it...

Pete Hanson · 01-04-2010, 08:56 AM

If I let my tank fill up to the top like you said yours was I will have a leak coming from the underbelly. If I bleed off some of the grey water before it gets that full (I would say over filled) then I have no problem. Being to lazy to investigate, I have simply not let it overfill. Maybe this spring I will crawl under there to see if there is something that can be done with it.

Army Guy · 01-04-2010, 10:11 AM

Don't the tanks have a vent located somewhere on top of the tank. Possible that when overfilled, it went out the vent and leaked. On mine, I have forgot to open the grey and have had it fill up in the shower. Once I get out of the shower, I go and open the valve but I have never had any issues with it overflowing. Again - good luck. Rick

Art-n-Marge · 01-04-2010, 10:28 AM

Yup, I had the same problem on a different rig just like Pete Hanson described. I also did the same as Pete. I think the leak is at the top where the drain connects to the tank. Avoiding the overfill will prevent the problem. This doesn't fix it, just avoids it. However, I wouldn't tolerate this with the Black tank.

Like Pete suggests, I think you will eventually need to get in there and fix the leak. It is not unusual to know that the tank needs to be drained as it starts to backfill at the shower/tub, but there should be on leaks.

P.S. - There are many stories of this kind of failure. While the tanks are supposed to be installed to support the weight of a full tank, I don't think this is always the case and a partially filled grey or black tank could cause a problem. I just try to avoid that. I do travel with about 10 gallons of fresh water which is used for bio breaks but is far less than full or almost full tanks.

P.P.S. - After I traded in my old TT and paid for the Monty I did let the dealer know about the grey tank and the brake problems on that TT. They said, they give trailers a good checkout before reselling. I hope they fixed these problems. For any naysayers, the TT also had 5 month old about 1,000 miles new Goodyear Marathons, a 30 amp Surge Guard, a 1500 watt inverter and the rig was so clean it was like new, so it wasn't like I passed on a piece of junk.

scductman · 01-04-2010, 10:34 AM

The tanks have a vent in the top but they are sealed and go up. They will hold water untill they run over unless they are cracked at the top which is normaly where they crack. I have had two of mine out. replaced one,repaired one. I cut my pipes at the top and put rubber nohub bands on them to take the pressure off of the lines had no problems since.
bobby

exav8tr · 01-04-2010, 12:16 PM

I have been "summoned" to the shower before to be shown the tank was full. Has happened numerous times (that's how we know when to empty the gray tank). Have had no leaks underbelly from this situation, everything held until I could get outside and "open the chute" or pull the handle for you techies.........lol. So far so good.

dsprik · 01-04-2010, 12:17 PM

As mentioned above, typical is a crack where the neck connects to the tank on top. Leak will occur when tanks are full only. My 2007 3400 had BOTH grey tanks replaced last spring for this reason after working with this situation for a couple months in FL waiting to get back to my dealer in MI. It is a workable situation on a temp basis while waiting to get the tanks replaced - just don't let the leaking tank(s) fill all the way up before dumping. Several others have experienced the same thing...

kmh3212 · 01-04-2010, 01:51 PM

My grey tank cracked when my wife took a shower and filled the water up to her feet and the tank cracked. My tank had a vertical crack from near the bottom of the tank near the drain hole almost to the top of the tank. Big job to replace. The tank was about $150 plus shipping. Extended warranty paid for mine. Bill was over $1000! It can be done yourself if you have a little plumbing experience and a lot of patience.

jackandh2o · 01-05-2010, 02:30 AM

My thanks to one and all. I do have an extended warranty but they have to replace parts for it to take effect. I was going to pull the underbelly myself and look up in there but it pretty much sounds like the tank cracked. I just didn't want to pay for labor if it was something that had come loose. We are home now so I think I will run some water and see how full it gets before it starts leaking. If it starts leaking before it is full then I would assume that I have a crack in the tank. I already have one in my head.

Again,
thanks to all.

Ray

richfaa · 01-05-2010, 03:40 AM

Our Extended warranty paid for black tank replacement less 50.00 ded and tax. nearly 800.00. BTW we leave our Grey tank (bathroom tank) open.

jackandh2o · 01-05-2010, 04:03 AM

Rich, just curious, if you leave the gray tank open how do you flush the dump hose after you drain the black tank.

Ray

dsprik · 01-05-2010, 05:14 AM

On our 2006/2007 Montanas we have a backflush that we run for a bit until we get clear water coming out of the tank - should have a clear 45° elbow, or at least a clear section near the gate valve. That should flush the hose. Also, you can flush with the galley grey tank, but it is not quite as clean as the bath grey.

CmdrDewey · 01-05-2010, 07:39 AM

I have been there and done that. Mine cracked right at the bottom near the drain and ran up about 6 inches. I tried, unsuccessfully to fix it but then a mobile repair guy fixed it for $145. It has been good for over a year now. I took the skin down and put it back. One person can put the skin back in several hours, two can do it in 1/2 an hour. Eterna bond makes a tape that they say can fix those leaks. I bought a 50' roll but haven't had to use it yet.

loua_loua · 01-05-2010, 07:40 AM

I read your post and actually had the very same problem. We were camping in August in Florida and a guest who was staying with us mentioned to me that the water was backing up into the shower basin and looked like it was draining slowly. I went outside and low and behold, water was draing from the underbelly. I opened the drain and thought that was that. When we got back to Pennsylvania, I took it to a Montana dealer and they had to replace the grey water tank as it was cracked in three places. Replacement cost was around $1000.00 including labor ouch!!!. We bought our Montana Big Sky second hand so I don't know exactly when this problem could have happened, but needless to say, I never travel with full tanks as I don't believe the structure can take the weight of all that water.
Hope you don't find you have to replace the tank because part of the reason the cost was so high was because the dealer had to re-route some of the plumbing on our 2004 3670 RL.... I would have a dealer check it out unless you feel like dropping the underbelly and can inspect it yourself......Good Luck

HamRad · 01-05-2010, 02:30 PM

Ray,
Ours did exactly what yours is doing. Even standing in the shower water sounds very familiar! Our leak turned out to be where the drain from the tank connects to the main sewer drain line. We used plastic radiator repair kit. So far so good. Main trouble is getting the underbelly covering removed and then reinstalled. I'd check it out there first. If it is not leaking there then it is probably on top and then you have to remove tank or cut hole in floor and come from the top! Some folks have actually done that from what I've heard. I would not do that.

Good luck.
Dennis

jackandh2o · 01-05-2010, 05:48 PM

I've got a dentist appt tomorrow so it will be Thursday or Friday before I get back to this. I think I'll hook up to water and run some into the tank and see when it actually starts leaking. Depending on what I find then I will feel better about making a decision then. Either I mess with it myself or haul it down the hill to Bullhead City to the repair shop.

I will keep you posted and thanks again for all the help.

Ray

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