Forum Discussion

howardmcc's avatar
howardmcc
Explorer
Aug 01, 2016

97 Coaching Catalina Plumbing Issues

I recently bought a 97 Coachmen Catalina and on our first trip I used the bathroom sink and noticed that as I ran the water it would come up in the shower and until I turned it of it kept filling up.

Since that time I have tried four different things:
1. Used a RV safe drain cleaner, which did nothing.
2. Used a plunger to clear the line and nothing changed.
3. I took a 25' hand auger and snaked the shower drain, bathroom sink drain and nothing changed.
4. I used the same drain snake and ran it down both of the vents and nothing changed.


Before taking the above steps I made sure that the gray water tank was empty and I checked to see if there was any clean outs and there are none.

I worked as a plumber many years ago and I have never been faced with this problem or anything like it. Has anyone had this same problem in the past? If so, how did you fix it, what did you find and what should I be looking for? I am open to all suggestions?

We are taking off on a 5k trip west in 19 days and would like to resolve the problem. Any help or suggestions?
Class A

10 Replies

  • rockhillmanor's avatar
    rockhillmanor
    Explorer II
    Aug 04, 2016
    OK disconnect from your water and shut your water pump off.

    Get a flash light and step on the pedal of your toilet so it holds the blade open in toilet. Shine the flash light down it.

    The toilet is a straight shot to the black tank no p-trap so you will see if there is water near the top or not.

    If I were you, so you can get this 'fixed' and 'explained' to you in time for your trip I would call a CG near year and ask who they use for RV Mobile Repair.

    These guys 'come out to you'. They will come right out to your house or wherever you have it parked.

    They are VERY experienced of all things RV. AND are VERY reasonably priced. My bet is they will know exactly what is wrong within 10 minutes of stepping into your MH :W

    I use them for EVERYTHING on my RV. They have seen and worked on so many different problems like I said he'll know what it is and have it fixed in no time. They have all the parts and tools needed right on board their trucks. It will be the best couple bucks you have ever spent.
  • howardmcc's avatar
    howardmcc
    Explorer
    Aug 03, 2016
    I have opened both valves and there is some stuff comes out. I get more from the gray tank and very little from the black tank and I think that it is what the toilet dumps but not sure. I can say this that as much as we have used out bath and kitchen sink and toilet there should be a lot more than what comes out. I hope that this helps
  • rockhillmanor's avatar
    rockhillmanor
    Explorer II
    Aug 03, 2016
    howardmcc wrote:
    Sorry for the delay in getting back to you all.

    Something that I do not think I mentioned but when I check the system monitor panel it shows that the holding tank is 2/3 full and I have never gotten it to empty completely and the gray shows that it is empty. I have also read that in some cases the shower or bathroom sink could also go into the black holding tank. Have you heard this before?

    I also called coachmen service department and they agreed that it is a full tank issue. So based on coachmen alluded to, what is the best approach to resolving the issue? Do I run a snake up the 1.5 inch black line? I have visions of waste going all over me (like Robin Williams in the movie RV).Any advice would be very helpful


    Forget the gauges at this time.
    The bathroom sink usually does dump into the black tank.
    Showers don't.

    Before you start shoving stuff up your sewage lines answer this.

    1. Have you physically 'pulled each valve blade separately' for both the 'black' tank and 'gray' tank ?

    I.E. > Open one valve, close it, and then open the other valve.

    Are you saying nothing comes out of either?
  • howardmcc's avatar
    howardmcc
    Explorer
    Aug 02, 2016
    Sorry for the delay in getting back to you all.

    Something that I do not think I mentioned but when I check the system monitor panel it shows that the holding tank is 2/3 full and I have never gotten it to empty completely and the gray shows that it is empty. I have also read that in some cases the shower or bathroom sink could also go into the black holding tank. Have you heard this before?

    I also called coachmen service department and they agreed that it is a full tank issue. So based on coachmen alluded to, what is the best approach to resolving the issue? Do I run a snake up the 1.5 inch black line? I have visions of waste going all over me (like Robin Williams in the movie RV).

    Any advice would be very helpful
  • rockhillmanor's avatar
    rockhillmanor
    Explorer II
    Aug 02, 2016
    OP so what did you find out? You got all us curious as to what the problem was!:C
  • Dutch_12078's avatar
    Dutch_12078
    Explorer II
    Aug 01, 2016
    rockhillmanor wrote:
    FYI:
    Some RV's also have a third tank called the galley for gray. I doubt they had that in 97 but I don't know that for sure.

    I've heard here on the forum that that 3rd tank valve for the galley tank can be hard to find.

    Is Your coach a Class A? I thought Catalina depicted Travel Trailer.

    Our '95 Coachmen Catalina was a Class A and did not have a third "galley" tank. Our bathroom sink drained into the black tank via a wet vent.
  • rockhillmanor's avatar
    rockhillmanor
    Explorer II
    Aug 01, 2016
    FYI:
    Some RV's also have a third tank called the galley for gray. I doubt they had that in 97 but I don't know that for sure.

    I've heard here on the forum that that 3rd tank valve for the galley tank can be hard to find.

    Is Your coach a Class A? I thought Catalina depicted Travel Trailer.
  • rgatijnet1's avatar
    rgatijnet1
    Explorer III
    Aug 01, 2016
    After you have made sure that both waste tanks are empty, leave the two valves open and put a bucket under the sewer outlet.
    On many coaches, the bathroom sink empties in to the black tank and is used to flush the pyramid of poop away.
    It is pretty common for the shower to back up when the grey water tank is full. That is the low point and it lets you know right away when the tank is full.
    On most coaches the kitchen sink dumps in to the grey water tank but you seem to indicate that it may be going in to the black water tank since it does not back up in the shower.
    To me it seems that you may have a blockage at the grey water tank drain and the tank is really full.
  • howardmcc's avatar
    howardmcc
    Explorer
    Aug 01, 2016
    Rockhillmanor - what you explained makes total sense and that is something I am going to try. It seems that I am never able to empty my holding tank but the gray tank is easy to empty. I thought that there was something affecting the sensor. I should also say that the kitchen sink drains fine and does not back up in the shower.

    I would have never thought of that. I will update as I know more.

    Howard
  • rockhillmanor's avatar
    rockhillmanor
    Explorer II
    Aug 01, 2016
    I have personally witnessed RV's where the label above the holding tanks were reversed. Gray water sticker over black tank valve and black water sticker over the gray tank valve.

    Run the kitchen sink, does it fill the shower also?

    If both sinks make water come up in the shower you have a full gray tank.

    Your gray valve is either marked incorrectly as the Black Tank or you are simply pulling the wrong lever.

    I'm betting if you pull the valve you think is the black tank it will be filled with gray water.:W

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