Grey tank access question

[JHinman]

The grey tank on my Arctic Fox drains really slowly. It seems to flow well at first, then subsides to a trickle.

I took a couple of buckets to the rig in storage, and opened the valve. Over the course of an hour or so I got another 5 or 6 gallons out of the tank.

The dealership says it drained OK for them.

I’ve heard that sometimes the drain can be partially blocked by the disk left by the hole saw when the drain is installed. I’d like to check that - but how does a person get access without completely cutting off and rebuilding the drain manifold? There are too many bends to get a flexible borescope to the valve.

Is it reasonable to dismantle the actual gate valve? It looks like it is held together with four bolts. Would I just muck it up and have a leak forever if I tried?

I’ll attach a photo of the actual valve.

[Mudfrog]

The slide valve itself is sandwiched between flanges.



Remove the four bolts, spread the flanges apart, and the slide valve itself will come out. Hopefully there's enough play in the piping. There's a rubber seal on both sides of the valve so you shouldn't have a problem with leaks if you reinstall correctly.