Gray Tank Valve Stuck

[Starguy]

On our recent trip, the gray tank valve stuck. Fortunately i was able to find an RV tech who solved the problem so we were not delayed en route. What he found was interesting. The cable instead of directly attached to the valve, made a large loop creating a lot of play and friction. There was a small amount of corrosion that ordinarily would have been a problem if the cable took a straight o route to the valve. This is a new trailer, and the tech noticed the coverings over the valves had been taped as though work had been done or something replaced. The valve has alway been hard to open and close, so the redundant cable would explain the problem. We were able to free the cable with lubricant and get it to work (I plan to keep it lubricated), but i am thinking I should have the valve and cable replaced. The TT is now out of warranty, but I don’t want to press my luck, have it happen again, and be somewhere where it will be difficult to fix it. I can’t image that this is the original design and someone replaced the cable with what was available at the time-we bought the trailer new.

[l1v3fr33ord1]

Starguy-

Cable-operated valves should have guidelines for the "entry angle" and bend radius of the cable. Thus, a correctly-installed cable could include a loop of what appears to be "extra" cable. See page 2 of this link for an example of installation guidelines:

https://www.valterra.com/download/10546/

[Starguy]

Thanks for the info. I don’t have a picture or any measurements to know if the cable is within the guidelines, and I don’t want to undo the tape to take a look. The tech did secure the cable at several points to limit movement. I will keep the cable well lubricated at the exit point and take my chances, but if i notice increasing resistance, relook.

[ScopeDope]

Wondering, how do you lubricate it... my black water valve is stuck in... can't dump.

[Starguy]

The cable of my gray tank became rusted from exposure to water sprayed up from the road. Because the cable is coiled and not directly attached to the valve, enough pressure could be applied to get it to slide in the sleeve. After the mechanic removed the cable, and straighten it, he finally worked it loose. He then applied a lubricant that also cleans off the rust that allowed it to slide in the sleeve. After is was reattached it works fine. Now every time I empty my tanks I lubricate both cable at their exit point, opening and closing them to be sure the lubricant gets distributed at the point of exit. So far I haven’t had any further problems.