Cracked black water tank

[RichieRich-SUN]

Hi all !
I recently purchased a 1996 Sunline T-1700 what looks to be in somewhat good shape , slowly checking each component , option and appliance to see what needs repair before the next camping season starts in the northeast.
While I was inspecting the brakes I crawled under the camper frame only to find a crack in the black water tank near the fitting that leads to the shut off valve. The crack is about 4 inches long .
I am looking for a few ideas on how to repair this crack. I am wondering if this tank can be removed making repairs easier working on a bench than on my back under trailer.
I was told that a previous owner did not drain water out of the system causing the water heater tank to burst , that was replaced earlier this year by owner . Not much I can do now to check for water leaks elsewhere until the weather warms in the spring.
Any suggestions will be much appreciated , thanks Rich

 

[MACK C-85]

Here's a thread dealing with black tank repairs:

http://www.sunlineclub.com/forums/f71/black-tank-questions-with-pics-10555-2.html

Mack

 

[EMD_Driver]

If you have a dremel tool, it will make for a stronger repair. You can put one of the sanding bands on it and use that, to rough up the cracked area. You could even dig into the crack a bit, to help make the final repair stronger.

Once the area is sanded/roughed up, you can mix up a batch of patch... We used a scrap piece of ABS and cut through it several times. The sawdust is what you are after. Once you have enough sawdust, mix it with some ABS glue. The resulting paste is a super-strong patch. You can also use some fiberglass drywall tape, to help the crack from ever coming back. I did not use the fiberglass tape and we traded in that particular Sunline, so I don't know how well it has held up without it.

If you want any more info, please ask away!

 

[JohnGB]

Rich,

If you have access to an air compressor you can do a water system leak check, dry. Air it up to 30 to 40 psi and then seal off the incoming pressure. Ideal is to have a gage in the system but if you have a big leak you will find it fast. Even if no gage, let it stay filled for a few hours and if you come back and it is still fill with good pressure then odds are high you are OK and no leaks.

If the camper is suspect that somewhere in it's life before you they did not winterize it right then an air check before water is a good idea. A lot easier to clean up pouring air then water.... LOL

You really do not need much more then 40 psi to do this check. They sell an air chuck fitting that screws in the city water connection where you can add air. It has a schrader tire valve on it and a garden hose thread. Or you can make one.

Good Luck

John

 

[miamilakesco]

I recently had my sewage tank drop from the bottom of my rig due to rusted screws from the mounting hardware. It pulled out from the toilet side cracking in several places. What I did (don't know if this is the correct way but it worked) is pulled the tank completely out. Remember my tank cracked on the top side.I used 2 layers of fiberglass cloth and resin, a couple inches bigger than the cracks. That fixed the cracks (with no leaks) and made it stronger than from the factory.

 

[RichieRich-SUN]

Hi Mack,
Thanks for the link , looks like these photos will help me out very much, will spend some time reviewing after holidays ,thanks Rich

 

[RichieRich-SUN]

Hi EMD Driver,
Thanks for your idea ! I do have a dremel and will keep your advice in mind when I do the repairs , Rich

 

[RichieRich-SUN]

John B ,
Yes, I have an air compressor and fitting already , great idea . But wondering why I did not think of that Rich

 

[RichieRich-SUN]

Hi Miamilakesco,
Thanks for your response to my problem. Right now I am thinking dropping the tank to do repairs would be the best way to go . I have used fiberglass before for repairs with very good success , thanks for time and help, Rich

 

[JohnGB]

John B ,
Yes, I have an air compressor and fitting already , great idea . But wondering why I did not think of that Rich

That is the beauty of this forum. Just to talk about it and in many cases realize what we have at home might just do the trick as we never thought of that.....

Good luck

John

 

[rpbmd]

Have used Eternabond before on leaks and found it to be great stuff....Available about everywhere. Good luck............rpbmd

 

[RichieRich-SUN]

Hi rpbmd, thanks for the advice. I used tht sealing tape twice on a pool liner under water as pool was filled and it worked , has been two years without leaking . My concern is how this product works holding against water pressure. I went to there website and they do make a tape for that application , I will contact them to see if there product will work for my situation.
I crawled under the camper yesterday and after reviewing the repairs needed I will have to decide if I use the tape you recommend or pull the whole tank out, not sure at this point in time which way to go, if the tank removal process is to difficult . Rich

Have used Eternabond before on leaks and found it to be great stuff....Available about everywhere. Good luck............rpbmd

 

[frank-SUN]

Hi rpbmd, thanks for the advice. I used tht sealing tape twice on a pool liner under water as pool was filled and it worked , has been two years without leaking . My concern is how this product works holding against water pressure. I went to there website and they do make a tape for that application , I will contact them to see if there product will work for my situation.
I crawled under the camper yesterday and after reviewing the repairs needed I will have to decide if I use the tape you recommend or pull the whole tank out, not sure at this point in time which way to go, if the tank removal process is to difficult . Rich

Dropping the tank is certainly possible, but will not be fun.

I went through something similar when I bought ours. Here is a step-by-step how-to on how I repaired it: http://www.sunlineclub.com/forums/f71/how-to-abs-tank-crack-repair-10514.html

Although working upside down is never fun, it is completely doable. I'm coming up on 4 years and no issues. I like (and use) eternabond products, but I would not use any kind of tape in this situation.

- Frank

 

[RichieRich-SUN]

Hi Frank,
Thanks for taking the time to respond to my posting. Your photos really help the repair explanations come to life . Using a dremel and ABS repair method seems to be the on-going advice I have been receiving . I knew laying on my back using fiberglass and gel would never work , way to messy in that awkward position but your method does not look nearly as messy and much easier laying on your back. When the weather warms in the spring I'll stat the project, Thanks again, Rich