main holding tank, tanks?

[pdx437]

i have a 77 land yacht 29'

i am without a manual. can someone please explain the tank systems? my panel shows a main holding tank, auxiliary, etc.

just need some clarification.

cheers!

[Jammer]

Main holding tank = collects wastewater from the head (toilet). Also called a sewage tank or blackwater tank.

Auxiliary holding tank = collects wastewater from the kitchen sink, lavatory sink, and shower. Also called a greywater tank.

You should also have a freshwater tank on the display which is the supply of clean water that is pumped to the faucets.

[driftless]

If you don't have an owner's manual, I'd suggest you search this site or ebay to find one. I think it will make your life much easier in gaining an understanding of the basics. But, you'll get great answers here on the forums for just about any question you can throw out!!

By the way, I think I've read on these forums that the control panel indicators are not too accurate or dependable unless properly maintained.

[pdx437]

thanks folks.

would there happen to be schematic drawing of some sort that displays the operation of these tanks? not just function - but also location(s) eg. sewage hookup, where to fill freshwater, etc?

also - the switch for the water pump. i'll assume that means that after filling freshwater - this supplies the pressure needed. i guess unnecessary if hooking direct to a water hose?

thx again.

[Jammer]

The oldest owners manuals that Airstream has online are for 2002 classic. Nonetheless, these may be helpful since the systems are very similar:

Airstream, Inc :: Travel Trailer Manuals

Sewage drain is on the road (left) side just behind the wheels.

Fresh water fill and the city water hookup moved from year to year and I'm not sure exactly where yours is. On mine the fresh water tank fill is behind a small locked cover on the curb (right) side and the city water connection is on the road side behind a hinged panel, low, a couple feet behind the sewage connection and valves. I would guess someone with a mid 1970s trailer will be along shortly with more specific guidance.

[Jammer]

Originally Posted by pdx437

also - the switch for the water pump. i'll assume that means that after filling freshwater - this supplies the pressure needed. i guess unnecessary if hooking direct to a water hose?

Correct.

[pdx437]

great! one last question - where does the freshwater flush out? along with the sewage?

[arodriguez60]

My sister has a 78 and on hers the drain for the freshwater tank is above a small plate just behind the axles on the belly pan. you remove the plate and in the cavity is a drain plug

[Jammer]

Originally Posted by pdx437

great! one last question - where does the freshwater flush out? along with the sewage?

Ordinarily the fresh water is only drained at the end of the year when preparing for winter storage.

The fastest way to do it is just open a faucet and run the pump until the tank is empty. Then there is a tiny petcock drain (as described upthread) that can be used to get the last few quarts out.

Water will remain in the water heater and piping. There's a forum section on "winterizing" that describes the procedure for draining all this water and preparing the trailer for winter storage.

[Aage]

Here is the diagram for the layout of the grey and black tanks IF YOU HAVE the "full" (rear) bath. This is from the 1977 Service Manual.



Both tanks are directly under the rear bathroom, the grey on the curb side and the black on the street side.

They share a common 3" outlet pipe, each tank having its own "guillotine-style" valve with which it is opened or closed. The valves can be seen in the rear "trunk" from outside the trailer.

It is recommended to keep the black tank's valve closed at all times, and only open it to dump the contents when the tank is full (or when you are storing or winterizing). The grey tank can be opened after the black one has been drained in oder to rinse out the pipe and your sewer hose.

Are things becoming any more clear?

ps: here is the 1977 fresh water holding tank. It's ahead of the axles.