Toggle switch air tank drains possible?

[dslucas]

So I was thinking.....alot of standard industrial controls that I work with are 24vdc. Getting underneath my truck everytime I shut it down to drain the air and water out of the tanks can be kind of a pain. I was thinking of wiring in a 24v toggle switch in to two MAC valves with the 24v coils so I could simply blow off the tanks from a dash switch. I can get the type that normally fail closed, so I don't see a safety issue with this. Anyone have any input, or advice against this idea? Just curious what you guys think....

 

[quickfarms]

If they are not DOT approved they are not allowed.

Does your truck have an air dryer?

You could just add one

There are DOT approved drains that have a cable attached do that you can drain the tanks without crawling under the truck.

 

[dslucas]

Good point with the DOT approval. No I don't have an air dryer, I had planned on adding one at a later date. Looks like I am going the cable route.

 

[quickfarms]

The cables are available in a lot of different lengths .

Just make sure you route the cables so they do not get snagged if you go off-road

With a fresh air drier I have never had any water in my tanks. Just remember to not use alcohol injection with a air drier

 

[KsM715]

Do you know how many mods that are suggested on this site that are not DOT approved? Whats one more? A switch operated tank drain should be the least of anyones concern.

Id do it if I still had a truck.

 

[peashooter]

So I was thinking.....alot of standard industrial controls that I work with are 24vdc. Getting underneath my truck everytime I shut it down to drain the air and water out of the tanks can be kind of a pain. I was thinking of wiring in a 24v toggle switch in to two MAC valves with the 24v coils so I could simply blow off the tanks from a dash switch. I can get the type that normally fail closed, so I don't see a safety issue with this. Anyone have any input, or advice against this idea? Just curious what you guys think....

I've seen people talk about this before on here somewhere. I think its a fine idea if you just stick with the simple solenoid type valve, you might run into trouble with the 3 or 4 way type valves. I use industrial 24vdc stuff all over on my truck as well. True they wont be DOT rated, but there is probably lots on your truck already that isnt. Ive had DOT rated cable pull drains that have leaked too.
In case you havent heard about these, there is also something called an automatic drain valve that mounts to the wet tank and will automatically empty the water and can be found on ebay for about $40(no electric needed). THey make 24v heated ones also. A popular one is DV-2 (Bendix and some clones available). I'd go air dryer as well though....I'm trying to find one to put on myself.
below is a pic of the DV2

 

[ARYankee]

I thought about doing it one of two ways. The first would be with a timing relay that once the truck is shutdown would turn on both drain solenoids. The other option would be to add a toggle switch with that so you could enable or disable it when you want.

 

[dslucas]

Thanks, Peashooter...I'll check into that one. Was definitely thinking simple solenoid type, exhaust to atmo.
ARYankee- good idea. If you were going to go that route, you might as well pick up an Allen Bradley Pico Microcontroller. Simpler to wire, and very easy to program. I have a friend who set one of these up as a lighting controller.
My only concern with DOT is if I were in a wreck. You know how Lawyers can get these days, so from a legal standpoint Quickfarms is correct.
If I can find some that are DoT approved Ill post 'em up here. If I used this for offroading only, I wouldn't be concerned, but this truck will see quite a bit of road use as well.

 

[doghead]

You should be looking underneath the truck as often as you drain the tanks.

What gain is there in adding a component that will require maintenance/add a failure point?

 

[PETE BALLARD]

A properly serviced air dryer should protect the air system, i agree with doghead, keep it simple!!!

 

[rustystud]

I honestly like the idea of a mag valve controlling the drain, but practically speaking it could become a liability. On our busses which have between 9 to 12 air tanks we still use only manual tank drains. Mine you these busses are state of the art in technology, costing almost a million each ! They have more valves on them then you can shake a stick at ! They all have an air-dryer on them, like the Bendix AD9 on the older units. The newer ones are using a dual colescent self purging unit which costs over $600.00. The busses are also drained manually every 3000 miles. All tanks. 3000 miles does not take long in a transit buss. So if our busses are still using manual drains that should tell you something. Also the Bendix DV-2 self draining units can become stuck if your air-compressor is using any oil. It turns into a sticky goo which plugs up the drain system in the DV-2. Though I haven't seen much oil usage by my air-compressor in the deuce. Our busses are using air-compressors with a 90 to 100% duty cycle and some oil usage is normal. Maybe if you put a "ping" tank after the air-compressor and a Bendix AD9 type of air dryer, you could also use the DV-2 purge valve. If you are unfamiliar with a "ping" tank, it is a small tank about a 2qt to 1 gallon size that is mounted about 3 feet after the air outlet of the air-compressor. It collects the oil the air-compressors pass and is drained every 3000 miles.

 

[dslucas]

Doghead....good point. I do a complete walkaround and check for leaks underneath everytime before I start the truck, and do another one while waiting for the air tanks to pressurize.

 

[nchittendon]

I just picked up some drains with the cables. After driving OTR and having grown up with it, draining my tanks is like having to take a leak. Every chance you get, you do it. But if someone is looking for a way to avoid crawling under the truck, don't do it. Spending time under a 40+ year old truck that travels the roads should be a daily ritual. These things can hurt/kill quite easily if there is a malfunction. Treat it as such. Even in my road tractor which was only a year old at the time, I would do a thorough walk around every morning and night. Typically, it was the amount of time to polish off one cup of coffee.

 

[Hoefler]

I put automatic drains on my A3. Got them from Ericks. Simple and clean.
Pete

 

[Woodsplinter]

The ones from Erik's require no switches and are currently $40 ea. I haven't used them but it beats having to wire in a switch.

 

[patracy]

I've got the pull cables on one of my deuces. I love it. Although I find myself not crawling under it now to look at things.

 

[nchittendon]

I've got the pull cables on one of my deuces. I love it. Although I find myself not crawling under it now to look at things.

This truck is my project with my son. We have a schedule set up right now where every Thursday, no matter what, we go out and climb under the deuce and see what we can see. If he points to something and asks what it is, and I don't know, we go grab the TM and find out. If we see something that doesn't look "right", we go to the computer in the garage and search SS. He is 7, and knows so much about a deuce already it's scary. I wish my childhood was that awesome. lol

 

[DeucesWild11]

I put automatic drains on my A3. Got them from Ericks. Simple and clean.
Pete

Pete, you are awesome! I know I saw this somewhere and when I asked around people never heard of it. I know I wasn't going crazy!

Question: Do you hear them drain out from time to time? I assume only when water hits it?

 

[Woodsplinter]

This truck is my project with my son. We have a schedule set up right now where every Thursday, no matter what, we go out and climb under the deuce and see what we can see. If he points to something and asks what it is, and I don't know, we go grab the TM and find out. If we see something that doesn't look "right", we go to the computer in the garage and search SS. He is 7, and knows so much about a deuce already it's scary. I wish my childhood was that awesome. lol

Good for you!!

 

[rustystud]

This truck is my project with my son. We have a schedule set up right now where every Thursday, no matter what, we go out and climb under the deuce and see what we can see. If he points to something and asks what it is, and I don't know, we go grab the TM and find out. If we see something that doesn't look "right", we go to the computer in the garage and search SS. He is 7, and knows so much about a deuce already it's scary. I wish my childhood was that awesome. lol

I wish my son was as interested in my deuce as yours . He is only interested in his video games ! I envy you !