Black tank repair?

[turbojimmy]

Hi all -

My Allegro was starting to sink a bit so I pulled it out of its parking spot to reposition the ramps. I have pretty tall ramps in the back, but I didn't think they were tall enough to contact the black tank which is directly behind the left rear wheel. Maybe they're not - I don't know. In any event my black tank has a sizable crack in it and it's leaking. I never noticed before, but it had been repaired in the very spot it is now leaking. It's never leaked before so I must have aggravated that repair somehow.

Anyway I see there are plastic tank repair kits available. Has anyone used them and/or have recommendations?

EDIT: I put it back in its spot and leveled it and it's still leaking. It wasn't leaking before so something happened when I moved it just now. It wasn't the ramps - there's no way they'd reach it. I don't even see any signs of new damage to the tank. But whatever, I have a problem now.

Thanks!

[turbojimmy]

Thought I would provide an update....

The Plasti-Mend kit came in. Today I started grinding away whatever they used to repair it. It's not silicone like I thought. It's some sort of hard epoxy/filler. The more I ground it away, the bigger the crack got. It's huge. It goes up to where I can probably reach it with a brush for the resin and repair mesh, but it's going to be tough to clean up in there. The crack is wide so I ordered some ABS plastic as well. I think I can fix it - I really don't want to have to replace the tank.

[Passin_Thru]

Do not repair plastic with fiberglas and Epoxy. It won't stick. I agree with dougrainer, replace.

[gbopp]

turbojimmy wrote:
I'm going to try to seal it with a Plasti-Mend kit.
If the repair doesn't work I'll drop it.

Wise move. That's what I would do.

[turbojimmy]

Thanks all for the replies. I'm going to try to seal it with a Plasti-Mend kit. Tiffin covered everything in foam but from what I can see it does look easy to get out. If the repair doesn't work I'll drop it.

[wildmanbaker]

I'm afraid the Doug is correct. If you look on line for holding tanks, you can order a new one, but it takes time for them to make a new on, if you size is not a stock item.

[dougrainer]

You have a 30 year old Allegro with ABS tanks. The ONLY fix on a 30 year old ABS tank is to replace it. The ABS is old and weathered. Dropping a underbelly tank on a Allegro your year is not that difficult. No repair kit will adhere to your old ABS tank and odds are Tiffin still has the tanks available. Doug

[MWJones]

turbojimmy,
On the plasti-mend.com site they have a repair kit for ABS for 39.95. I have used one of these kits myself with very good results.
Be sure to use a repair kit for ABS.
Poly or fiberglass WILL NOT WORK on ABS.
Good luck.

[time2roll]

I can't see or touch the damage but if silicone held up pretty good you may only need to apply a few coats of the solvent mix itself and pass on the ABS cover. It was a PITN to get mine to fit just right and get solvent applied etc all at once. If you have a helper that part would go easier.

[turbojimmy]

time2roll wrote:
Black is probably ABS. Poly is usually white.

ABS is same as black waste pipes used in homes and is bonded with a solvent that temporarily softens the surface of the plastic so the two surfaces can bond.

I recommend a sheet of thin ABS to cover the entire crack in one piece. If it goes around a curve you can form the sheet with a heat gun. Clean and sand the area per instructions and glue the patch on. Silicone can be an issue so do not short cut the cleaning and preparation of the area.

http://www.plasti-mend.com/cart/index.php?route=product/category&path=59
(also check amazon)

ABS sheet

Great info. Thanks! I checked out their "Identifying your Plastic" link. I'm sure the tank is ABS based on their description and photos. I'm definitely going to go that route. The repair will have to bend, but I have a heat gun that I can use to form the curve.

[time2roll]

Black is probably ABS. Poly is usually white.

ABS is same as black waste pipes used in homes and is bonded with a solvent that temporarily softens the surface of the plastic so the two surfaces can bond.

I recommend a sheet of thin ABS to cover the entire crack in one piece. If it goes around a curve you can form the sheet with a heat gun. Clean and sand the area per instructions and glue the patch on. Silicone can be an issue so do not short cut the cleaning and preparation of the area.

http://www.plasti-mend.com/cart/index.php?route=product/category&path=59
(also check amazon)

ABS sheet

[turbojimmy]

time2roll wrote:
ABS? I have used and recommend Plasi-Mend.
Polypropylene? Probably needs welded by a pro.

I don't know what it is. It's black if that means anything. How can I tell?

[turbojimmy]

MrWizard wrote:
i think you will need to empty the tank for the repair
the sooner the better
will probably need to let the tank dry
and clean out the crack, before attempting the repair

Yes you're probably right. All I had in it was a bit of fresh water and a sanitizer tab. It's already emptied itself. The crack is a big one and runs up the side - but I can get at it. It was all gooped up with silicone. I'm surprised that it didn't leak until now and also that I didn't notice it until now.

I see Permatex makes a kit with a 2" x 4" piece of fiberglass and some epoxy. It has decent reviews on Amazon. I'd need 2 or 3 of them at $12 a pop but it's better than replacing the tank. I don't know if I could even replace it anyway. It looks easy to get out but it's 33 years old.

[time2roll]

ABS? I have used and recommend Plasi-Mend.
Polypropylene? Probably needs welded by a pro.

[MrWizard]

i think you will need to empty the tank for the repair
the sooner the better
will probably need to let the tank dry
and clean out the crack, before attempting the repair