Gurgling in kitchen sink while using shower mystery

[classact]

OK, mystery solvers out there:

Melbourne 29c, 2007

[classact]

Sorry..hit "send" too soon.

When my wife uses the shower when we are dry camping, not hooked up to sewer, the drain gurgles a LOT. You can even see the water bubbling up toward the bottom of the kitchen sink. This never happens when we are hooked up to sewer, and it only happens after the 2nd or 3rd shower.

Could this be a vent issue? If so...how do I check on it? It's a mystery to me that it only happens when we are dry camped.

Ideas?

Thanks,
Mike

[Tweety]

When you are hooked up to a sewer do you leave your drains open?

[classact]

Tweety - yes, grey water valve is open when hooked up to sewer; But note that this only happens when *not* hooked up to sewer. I can also ad that the grey water tank is not approaching full when this happens either, FYI.

[SmokerBill]

I agree with your thought that it could be a vent issue. If the vent is plugged up, two or three showers could be building up enough pressure in the gray water tank to cause the pressure to escape though the kitchen sink drain trap.

I think there's a vent pipe coming out of the roof. Check that for obstructions. Maybe a mud dauber built a nest up there.