Manual Override on Electric Dump Valves

[Protagonist]

Originally Posted by zigzagguzzi

Is new always an upgrade? Think about it! Jim

Given that Airstream Interstates have only been around for 10 years now (first produced in 2004), by your standards they're all new!

But in any event, I think the last time an Interstate came with a slinky and manually-operated dump valves was 2007, so macerator pumps and electrically-operated valves aren't exactly new by the standards of an Interstate owner.

[raddocc]

I took off my auto drain motors and the black tank drained like a champ. It must be my circuit board. I will open them manually until I can get it fixed. Thx for all the help and patience.

[73shark]

Originally Posted by raddocc

I took off my auto drain motors and the black tank drained like a champ. It must be my circuit board. I will open them manually until I can get it fixed. Thx for all the help and patience.

Care to share how you reached them?

[raddocc]

Originally Posted by 73shark

Care to share how you reached them?

I pulled the AI on to cement, since it was too tight to bring both of my arms up the secure both sides of the bolts, I was on one side with a ratchet and my wife had the other side with an Allen wrench .

[J. Morgan]

I wonder why the engineers didn't provide a means of making an emergency dump in case of failure?

Gravity never fails.

[Boxster1971]

Originally Posted by J. Morgan

I wonder why the engineers didn't provide a means of making an emergency dump in case of failure?

Gravity never fails.

Good question!


- - Mike
2013 AS Interstate on 2012 MB Sprinter

[Protagonist]

Originally Posted by J. Morgan

Gravity never fails.

So, what emergency alternative would you install in case of a valve failure? Another valve?

The only place in the whole system that gravity is taken OUT of the equation is at the macerator pump. For getting wastewater TO the pump, you ARE using gravity.

[J. Morgan]

Yea another valve plumbed in where gravity would work sounds like a smart move to me.

The OP seems to have gotten the tank(s) to drain via gravity if I read things right.

An emergency valve right here might have been a good idea.

[Protagonist]

Originally Posted by J. Morgan

Yea another valve plumbed in where gravity would work sounds like a smart move to me.

I think maybe you missed the point of my admittedly snarky comment. The existing drain valves already drain the tanks by gravity; nothing new has to be done to drain the tanks by gravity, so I still fail to understand why the whole "gravity" thing started on this thread.

The only problem is that the valves are electrically operated, not manually, and there's no good way to operate them manually after the motor quits working except to crawl underneath.

The only practical engineering fix would be to get rid of the electric motors and go with push-pull cables leading from T-handles to the valves the way they used to do in the old days. Then there are no motors to quit and you're always operating the drain valves manually. But then you're still faced with the dilemma, what do you do if the push-pull cable breaks?

[J. Morgan]

My point is,,,,

What happens if the brakes in your car fail?

Why is your vehicle equipped with an emergency brake?

I think maybe that there should be a emergency method of discharging waste that does not involve disassembly.

I know that anything I would ever build would have such a provision.

[Protagonist]

Originally Posted by J. Morgan

What happens if the brakes in your car fail?

Why is your vehicle equipped with an emergency brake?

I think maybe that there should be a emergency method of discharging waste that does not involve disassembly.

I know that anything I would ever build would have such a provision.

I wouldn't. Not being able to dump the holding tanks is not a matter if, "If this doesn't work we're all going to die!" Unlike brakes, which are a matter of life and death and therefore require a backup. There is such a thing as over-engineering.

If I worked for Airstream, what I would do is realign the valves so that they're easier to reach— they don't have to work vertically with the stem on top; a sluice valve can work just as well by sliding sideways or diagonally or even sliding down to open— and make it easier to disconnect the motors from the valves, perhaps by just pulling a cotter pin on the valve's operating stem. Then after the motor is disconnected from the stem the person who pulled the pin could insert a tool (Phillips screwdriver?) into a hole on the stem to provide a handle for prying the valve open. After the problem was solved, the user would just have to reconnect the valve with the motor and reinsert the cotter pin, and hey presto the job would be finished.

[J. Morgan]

Having to get poop on me in an effort to drain my poop tank on my driveway is kind of an emergency...

My point is that he engineers should have provided a practical means of dealing with the payload for when the valves fail to open as designed.

I don't know if it is true, but I have read that the dump valves are more reliable when the stems point up because garbage is not so prone to collect in the slides.

[avanti]

The best practice solution to this problem involves manual valves located close to the edge of the vehicle plus the following (readily available) fitting:



This permits a macerator to be permanently connected to the rear of the fitting while preserving the ability to do a gravity flush using the front-facing bayonet fitting and a slinky.

Electric valves are a needless complexity that tend to be used to make up for poorly-thought-out pipe layout.

[J. Morgan]

Frankly there is little doubt in my mind that much of the design work done by OEM 's of all kinds is to get the customer into the dealers service department.

Am I bad for thinking this way and resenting it?

[73shark]

Originally Posted by J. Morgan

Why is your vehicle equipped with an emergency brake?

Actually motor vehicles are equipped w/ a parking brake, not an emergency brake. If you doubt this, just try stopping by only using your parking brake.

raddocc didn't get poop all over him by opening the valve(s) manually. The open valve just allowed the tank contents to get to the macerator pump.

[J. Morgan]

Might be true, I might have misread but it seemed to me as if the op removed the valves....

If that is the case I don't know how the poop would have been stopped...

Frankly I am too lazy to read back through right now.

If for one reason or another , if an e brake or parking brake is all you have a person might be glad to have it.

An e-brake/ parking brake may on occasion serve a dual purpose, and in most every case a properly functioning parking brake is capable of locking a vehicles back wheels.

[J. Morgan]

I stand corrected...

I mustered the energy to read back over the thread, I was wrong about the valves having to be removed and the poop bath that I assumed.

My apologies.

[73shark]

I agree that the parking brake will lock the wheels at rest. But it won't if they're turning.

[J. Morgan]

I think that a properly operating parking brake will lock the wheels on most any car made in the last 40 years.

When I was younger and not so smart I used to use the parking brake to lock the rear tires to induce a spin.....