Imagine Grey Tank Dump Valves Stuck Closed

[Keebler]

I had this same binding issue and it was actually a problem with the cable bend radius. Changed it out and been good since.

[Cleetussnow]

I had this same issue surprise me last weekend on our first trip. Handles would not budge at the dump station except the forward grey tank. Bad news. Drove it home and starting mulling what to do. Just wrapped the job up moments ago.

First I removed the threaded sleeve from the bracket that holds the cable to the trailer. Had to remove the t handle obviously to back the cable out. Then I dipped the cable end in PB blaster to soak overnight in a plastic bottle. Next day I grabbed some vice grips, the most loathsome tool devised (except when you need it) and started to try to loosen the rod with twisting action, one grip on the rod, the other on the threaded steel sleeve. No go.

I grabbed a torch and some PB spray, and started alternating heat and lube on the sleeve, and then twisting action until I got movement. Took about 20 minutes to free the rod, then another 10 to pull the rod all the way out of the sleeve. Didn’t seem like it would free up, but I got it. It was not easy nor fun.

Then I worked the rod a couple dozen times back and forth in the sleeve with Pb blaster and anti seize compound on the rod, cleaning the rod in between until the compound had no dirt or corrosion on it. Reassembled and good to go. Did this with the black and rear grey tank valves.

Final analysis is the design has a critical flaw. The threaded sleeve is made of steel, and the rod is aluminum. If the part comes into contact salt and water, a galvanic reaction occurs between the 2 different metals. They can cleave together and often they won’t separate no matter what you do. I’ve seen this with other machinery and basically its a cutting wheel solution. I’d say I got lucky with freeing the rod.

So now what. I have a valtera gate on the end of the sewer system that I installed as a back up in case I forgot to close a valve when dumping or something. Also one of the grey tank valves never quite closed so I always got a drip. Valtera gate fixed it. I am wondering if I should leave the cable gates open and never use them again, and just use the valtera. The valtera has less things that can go wrong. I can’t see a reason why not.

The alternative is to be super vigilant and lube those sewer cables on every trip and just be on it constantly. But I fear leaving it over winter could leave me under the trailer with a torch and vice grips again. The cable system has a 3 failure points by my count...the cable connection at the gate, the rod and sleeve that failed on me, and of course the gate itself can seize. Don’t count out the cable itself locking up in there somewhere with a kink or something.

Thoughts?

All valve cables were frozen again after taking the trailer out for spring use (I dry camp in winter). I am going to do away with the grey tank cables and install inline gates with a simple pull rod on each at the terminus of the grey tank pipes into the main dump pipe. Ill jack the pull rod gates full with grease by adding a Zerk to the gate housing. I wont be able to use water in the winter but i never do anyway. The inline gates will be below the Camoplast. Its a trade off.

I cant do this to the black tank so i am going to replace the cable. I suspect there is a poorly routed cable up under there adding to the issue. I will grease the new cable before installing it and i will see what can be done to that gate as well. I will leave the black valve open next winter and this way i wont get surprised again at the dump station like last year. I will just use the valterra at the end if the black tank cable locks up again.

I hate this problem. Had i known about this issue in advance I would have had a whole different approach to seasonal maintenance.

Ill report back on the project next week.