Thanks!  I got the tank out disconnected the toilet as you described.  The
cover was rusted completely through.  The tank is cracked at the vent port
and at the valve attachment point.  The front angle iron has some detaile
cuts in it for the valve opening.   The belly is also pretty corroded.  I'm
going to see what kind of feedback I can get on repairing the tank.  Also
I'd be interested if anyone knows of replacement tanks.  Thanks again, I'll
keep you posted.
Chris 70 sovereign 31'
-----Original Message-----
From: Harvey Barlow <[EMAIL PROTECTED]>
To: Multiple recipients of VACList <[EMAIL PROTECTED]>
Date: Saturday, March 24, 2001 4:16 PM
Subject: [VAC] Blackwater Tank Removal and Repair

>It is a common problem.  Not much fun but manageable by the average person
>who can use basic hand tools.
>I have done two recently, my daughter's '72-27' and my own '66-22'.  A list
>member recently advised that he had an estimate from an RV repair shop for
>over $800 for repairing his and that was not including the probably
>new black water tank, new holding tank cover, and assorted parts that will
>probably be required.
>Here is a brief summary of the steps required:
>1) Remove the toilet which should have two 1/2" nuts holding it to the
>floor, front and back.  Remove the fresh water flush connection from the
>toilet of course.  You should be able to locate the front nut by depressing
>the flush pedal and looking back inside.  There may be a push out plug on
>the top rear of the toilet which will permit access to the rear nut with a
>12" extension and socket.  If it is a standard Thetford toilet you can
>contact Thetford for a print, or visit a local RV store to visually inspect
>one.  Experienced RV mechanics on the list can tell you more detail about
>the toilet.
>2( Remove the toilet flange by rotating clockwise after soaking with Liquid
>Wrench at the junction with the holding tank if you can get to it.  (The
>toilet flange is installed from above through the bathroom floor after the
>holding tank is in place.  The holding tank has a threaded fitting which
>toilet flange screws into.  It "should" be removable with Liquid Wrench.)
>If you accidentally break the tank or tank flange or find breaking it is
>required in order to separate them, don't despair.  The most likely cause
>sewer odor and a very common problem is a broken tank.  Chances are you are
>going to be purchasing a replacement or having your tank repaired anyway.
>3)  Disconnect the holding tank vent stack from the tank.  It may have a
>slip joint with clamp or you may have to cut with a hacksaw then reinstall
>using a PVC or ABS collar.
>4)  Remove the front and rear angle iron tank supports.
>5)  Drop the holding tank cover.  You will have to remove the tank cover
>patches which close the opening around the dump valve assembly in order to
>drop the tank.
>6)  Remove the holding tank dump valve assembly by removing the four
>stainless 1/4 20 screws and nuts that hold the two halves of the dump valve
>assembly together.
>7)  Some trailers may have wood screws penetrating the folded outer edge of
>the holding tank cover screwed into the plywood floor of the rear
>compartment.  If yours does, the screws must be removed to remove the tank
>cover.  I don't think yours does.
>8)  You will most likely discover that the top of your holding tank is
>broken.  Most are molded of polyethylene plastic which nothing will adhere
>to very well.  A list member, Nick Novia, knows an industrial plastics
>company in CT who will hot air weld the tanks for approximately $100.  I
>others can provide sources from which to order a replacement tank.
>9)  Retain your holding tank cover for a pattern and have any good sheet
>metal shop bend a replacement.
>10)  Throw away the rusted angle irons.  They are made of standard 1 1/4"
>angle that can be purchased from any steel supply company or Home
>Improvement store, cut to length, primed, and painted.
>More questions?  Don't hesitate to ask.
>Good luck on your tank replacement.
>Harvey Barlow
>Lubbock, TX
>WBCCI # 1171, WDCU, VAC
>----- Original Message -----
>From: Patty & Chris Peters <[EMAIL PROTECTED]>
>> the odor that eminated from the bathroom.  Upon closer inspection outside
>> quickly discovered a portajohn odor at the rear of the trailer.  I figure
>> it's the blackwater tank.  This morning I drilled out the rivets and took
>> out the rear angle iron cross member.  The outer shroud was pretty well
>> deteriorated at the rear base.  The angle iron has some surface rust but
>> looks pretty good.  This has raised a couple of questions;
>> 1.  What else do I need to disconnect in order to pull out the tank and
>> 2.  How do I detach the toilet from the tank, does the plastic shroud
>> the toilet come off to reveal bolts, how many?
>> 3.  Do I need to disconnect the dump valve?
>> 4.  I've been searching the threads for over an hour and haven't found
>> step by step dialogue or info re: service bulletins, is there anything
>> archived?
>> 5 Am I getting in over my head and how much would I expect to pay for a
>> repair?
>To unsubscribe or to change to a daily Digest, please go to
>If replying back to this message, please delete all the unnecessary
>text from your reply.

To unsubscribe or to change to a daily Digest, please go to

If replying back to this message, please delete all the unnecessary original
text from your reply.


Reply via email to