Thor Forums

[Handy]

I removed the p-trap which was clean and inserted a 1/4" hose through the drain pipe and down to where it enters the holding tank below the drawers. I also inserted the hose from the AAV down to the same point and it appeared to be clear. Also considering that the drain speed is normal without the AAV indicates that the pipes are clear. There is only one 360 Vent on the roof so I will assume that the black and grey tank vents combine into this. The vent is on the opposite side of the motorhome from the kitchen sink. I looked at the grey tank configuration closer this morning and it is very custom! It is about a 3" deep pancake spreading about 4'x4' under the floor with a deeper collection area on the opposite side of the motorhome by the main drain. There is a little finger at the edge of the grey tank where the drain pipe from the kitchen sink enters it. The grey tank is secured to the bottom of the floor at this point to keep it high and then slopes downwards to the other side of the motorhome at the main drain. My thoughts are that all the other drains are working so the kitchen sink end of the grey holding tank must not be benefitting from the holding tank vent. On another note, while inspecting the grey holding tank I found a cluster of 8-10 hoses, conduit, and wires wedged between the holding tank and the top of the chassis on the low side of the tank where it is supposed to rest on the chassis. Over time, especially driving with a full grey tank, these will get pinched between the holding tank and the chassis so they will need to be pulled out of there. Maybe this will affect my venting issue when the tank is able to come down a little more and rest on the chassis. Also, the abs pipe coming out of the grey tank is sloped upwards before it turns down to the main drain so I might have to add a couple of rubber couplings to allow it to stope downwards properly. I also found a rubber fuel hose pulled tight against a sharp metal edge a few feet forward of the gas tank in the rear.