Seneca suspension air dump

[Dananu]

Got air dump system installed yesterday. Bigfoot controls on 2014 by steps (not dash so not concerned with dump while traveling) switch installed there. Drops rear at hitch 4 inches. Also spent an hour under rig with wire ties replacing broken ones and finding wires a didn't like how secured or hanging.

Sent from my SCH-I545 using Tapatalk

[Robbbyr]

Very nice! Where did you get that dump switch?

[Dananu]

Originally Posted by Robbbyr

Very nice! Where did you get that dump switch?

Found it at used rv parts in Quartzsite Az. Isn't specific to dump. Think it was maybe a window switch, momentary DPDT and only used 1/4 of terminals.

Sent from my SCH-I545 using Tapatalk

[Robbbyr]

Thank you!

[ready2retire&drive]

Looks good this system sure makes leveling easier and stresses coach body less

[Crossingover]

Is the air dump system isolated from the braking system? I'm just concerned with compromising safety any time you mod the compressed air system.


Sent from my iPhone using Tapatalk

[Robbbyr]

Originally Posted by Crossingover

Is the air dump system isolated from the braking system? I'm just concerned with compromising safety any time you mod the compressed air system.

I plan on installing my system just as depicted in Dananu's picture by placing a tee in the air line between the leveling valves and the air spring itself. So to answer your question, it will not be any more isolated than it is stock from Freightliner passing through the two leveling valves to the springs themselves. Yes there are a few more connections, but air brake-rated fittings and line are pretty reliable.

I am going to use dump solenoids that have adjustable dump flow valves to prevent the suspension from emptying too quickly. I suppose in the event of a solenoid failure (sticking open) the compressor might be able to keep up enough to keep the parking brake from applying.

[ready2retire&drive]

"I am going to use dump solenoids that have adjustable dump flow valves to prevent the suspension from emptying too quickly. I suppose in the event of a solenoid failure (sticking open) the compressor might be able to keep up enough to keep the parking brake from applying. "

On mine I have put a ball valve between the air bag and solenoid just in case there may be a valve failure (air leak) so I can go underneath close the ball valve so the system can maintain air pressure to make it home and repair. My exhaust valve's are set at 50% which drops it down quite nicely.

[Dananu]

I didn't use ball valves, but opted to just carry a coupling that can replace the T in case of a failure.

Sent from my SCH-I545 using Tapatalk

[Abe padgett]

Can I install a dump valve on the tank that supply’s air to both airbags ?

[Robbbyr]

Originally Posted by Abe padgett

Can I install a dump valve on the tank that supply’s air to both airbags ?

I believe the issue with that approach is that air would still be "trapped" between the actual leveling valves and the airbags. I fear it would not immediately empty the bags. But if you went through the raising/lowering procedure the bags would then empty and not refill.

Just my guess based on the idea that air won't empty backwards through the leveling valves themselves.

[Dananu]

Originally Posted by Abe padgett

Can I install a dump valve on the tank that supply’s air to both airbags ?

I thought of that, but don't know if the actual leveling valves will still hold air In the suspension. You could manually drain tank to test.

Sent from my SM-G950U using Tapatalk

[MD3]

Originally Posted by Robbbyr

I believe the issue with that approach is that air would still be "trapped" between the actual leveling valves and the airbags. I fear it would not immediately empty the bags. But if you went through the raising/lowering procedure the bags would then empty and not refill.

Just my guess based on the idea that air won't empty backwards through the leveling valves themselves.

You are correct... the leveling valves fight a simple air down like a class A.

Even with the raising and lowering the jacks the leveling valves will reinflate the bags. This occurs until the tank air is depleted.

I’m planning on putting a T between each bag and the leveling valves. Both T will join and route to a ball valve. Then I can dump from the bags. the leveling valves will try to air up the bags as they dump so in turn I will have to continue dumping until the tank is also depeted.


-

[Robbbyr]

Originally Posted by MD3

I’m planning on putting a T between each bag and the leveling valves. Both T will join and route to a ball valve. Then I can dump from the bags. the leveling valves will try to air up the bags as they dump so in turn I will have to continue dumping until the tank is also depeted.-

If I understand your intent you plan to tie the two airbag lines together with a single valve to dump the air. I believe it was discussed earlier about tying the lines together, the concern raised is creating a situation where the roll stability of the chassis is compromised since air will exchange between the two springs while driving. Each side has its own leveling valve so it can adjust that particular airbag, and the manufacturer-installed air dump systems I have seen keep the two sides separate. Another owner may have installed a single valve system, not sure what his driving feedback revealed.

If you are planning on installing two ball valves, one in each line, you eliminate the issue I was describing. Sorry if I misunderstood.