Arctic Fox black tank valve glued in?

[Njmurvin]

I had a mobile service guy come out to quote me on replacing my black tank valve. The valve has been very difficult to operate (especially close) and is leaking a small amount.

After cutting an access door in the underbody to look at things, he concluded that the valve is glued to the black tank. He pointed out some hard white material at the connection and said it was glue. Oddly, there was a hose clamp there as well. That made no sense to me that they would glue it AND clamp it. And it's so close to the tank that cutting it off is not an option as it wouldn't leave enough for a new valve to be installed. So, he recommends leaving it open and installing another valve downstream where he has access.

These valves are prone to failure and need replacing from time to time. Is it normal for them to be glued like this or is it possible this white stuff is something other than glue? I'm beginning to wonder if this service guy knows what he's looking at.

[Bird_Freak]

You need a new repair guy. He is not so bright.
Its a simple fix that I have done several times.

[Njmurvin]

opnspaces wrote:
It's actually not that crappy a job if you plan through it. It's even easier if you have a way to dump at home. Find a way to access the valve and look to see which side of the tank it is mounted to.

• Figure out how to tilt the trailer using the jacks or leveling blocks on only one side so the everything flows toward the valve.
• Drain the tank and give it an extra 5 minutes to drip dry.
• Close the valve and reposition the jacks or blocks to tilt the trailer the opposite direction.
• Get some disposable gloves and a new valve.
• Crawl under and look at the whole drain path.
• Loosen but don't remove some downstream hangers to allow some movement in the piping.
• Pull the 4 bolts.
• There should be only a few drops of liquid coming out of the open joint.
• Remove the old valve and make sure you also remove the o-rings (1 per side of the valve).
• Replace with a new valve making sure to use the new o-rings that came with it.
• put the bolts back in and tighten them up.
• Tighten the downstream hangers.
• If necessary use a paper towel to wipe up the few drops that landed on the ground.
  
  

You make it sound so easy (and tidy)... tempting. It has been sitting for 8 months. Is it possible the liquid in the tank has evaporated by now? It was dumped the last time I used it. But you never get it all out.

[opnspaces]

It's actually not that crappy a job if you plan through it. It's even easier if you have a way to dump at home. Find a way to access the valve and look to see which side of the tank it is mounted to.

• Figure out how to tilt the trailer using the jacks or leveling blocks on only one side so the everything flows toward the valve.
• Drain the tank and give it an extra 5 minutes to drip dry.
• Close the valve and reposition the jacks or blocks to tilt the trailer the opposite direction.
• Get some disposable gloves and a new valve.
• Crawl under and look at the whole drain path.
• Loosen but don't remove some downstream hangers to allow some movement in the piping.
• Pull the 4 bolts.
• There should be only a few drops of liquid coming out of the open joint.
• Remove the old valve and make sure you also remove the o-rings (1 per side of the valve).
• Replace with a new valve making sure to use the new o-rings that came with it.
• put the bolts back in and tighten them up.
• Tighten the downstream hangers.
• If necessary use a paper towel to wipe up the few drops that landed on the ground.
  
  

[agesilaus]

If you thoroughly flush the tank with Dawn solution, fill it and let it sit overnight, drain and repeat a couple times then it should not be a dirty job.

[Njmurvin]

Rvpapa wrote:
... find somebody else to work on your rig.
Art.

Thanks to all for the thorough explanation of how these valves are installed and serviced. I am taking Art's advice and will look for someone else to replace this valve. I'd do it myself if it wasn't such a "cr@ppy" job. Thanks.

[Ralph_Cramden]

C Schomer wrote:
It looks like a pipe stub is glued to the valve and the stub is clamped into the neck on the tank so it can slide out after loosening the clamp. Even if that isn't so, it doesn't matter... It doesn't need to come apart there anyway. Take the four bolts out and replace the center section. Craig

Actually not a pipe stub, but a male to female adapter, the tank side fitting is male one end and the 4 bolt flange on the other. If you remove the hose clamp you are 100% correct. The whole shebang slides out.

This is a picture of an MDPE tank.



Notice the flange for hanging from spreader bars that is about 2" high and blow molded as part of the tank tank itself.

A ABS tank is formed from a sheet of ABS on a vacuum former then the flat top is glued on as well as the outlet fitting, the hanging flanges are 1/4" thick. An ABS tank will not have or need a hose clamp, and would of been a direct glued connection.

[C_Schomer]

It looks like a pipe stub is glued to the valve and the stub is clamped into the neck on the tank so it can slide out after loosening the clamp. Even if that isn't so, it doesn't matter... It doesn't need to come apart there anyway. Take the four bolts out and replace the center section. Craig

[Rvpapa]

Try another scenario. The tank and the valve are both ABS. The valve is glued to the tank. The clamp is there to prevent the valve from being pushed on to far when assembling (glue sets up real quick). Valve is normally changed as AGESILAUS pointed out. Finally and most important, find somebody else to work on your rig.
Art.

[Ralph_Cramden]

The tank in the pictures is MDPE, the valve and piping is ABS. No glue is used for the connection to the tank, and if it was it would not stick to the MDPE tank. Nothing "sticks" to MDPE for any length of time. What you see is sealant. If it was a hard connection there is no need for the hose clamp. In the OPs case ABS glue is black or yellow anyway, not white. The RV tech was blowing smoke. Most OEMs use electricians duct seal in that ABS to MDPE connection along with the clamp.

No need regardless to mess with that connection, as BobK points out.

[BobKrogstie]

Njmurvin wrote:
Does that mean you can take off the 4 bolts and slide the valve body out without cutting the pipe on the outboard side?

Yes.

[agesilaus]

People leave the old valve in, leave it open and install one of these.

Not an elegant fix but it works and is cheap

BTW I find it have to believe a valve is both clamped and glued in, normally people disassemble the sticky valve via the 4 bolts. Clean it and lube the stem (the metal rod) with silicone grease. Cycle the valve several times and reassemble. You have to get the tank empty and flush it several times with detergent solution (Dawn) before doing this.

[Njmurvin]

Does that mean you can take off the 4 bolts and slide the valve body out without cutting the pipe on the outboard side?

[BobKrogstie]

Here's another look at the black tank and valve. These pix were taken as I was replacing the valve body and gaskets.

[BobKrogstie]

The 3" Bladex valve is glued and clamped to the black tank. The 4 bolts of the valve can be loosened and the blade body itself can be removed for maintenance or replacement. You may have to loosen the 3" pipe on the output side of the valve to provide some play for removing the valve body.