Air bag pressure

> > Not to the pump, but to the tank.
>
>
> That'll be easy enough. Once I access the air, though, how do I run the pump independent of the system?

That is a good point. Ihave my compressor wired to run off of either house or chassis battery. Normally I just leave it in HOUSE. With the air hose connected, the compressor kicks in whenever I use air from the tank.

--
Hardie Johnson "Crashj"
1973 26 foot Glacier, White Thing
Raleigh NC

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Nick Chapekis writes...

> That'll be easy enough. Once I access the air, though, how do I run
> the pump independent of the system? For example, after I developed
> the leak in the air line, I could not run the pump on travel because
> the air just escaped through the leak in the line.

The pressure switch on the pump measures tank pressure. So, if you
bleed air out of the tank with the valves in Hold, the pump will turn
on when the tank pressure falls below the lower threshold on the
pressure switch.

But if you had a leaky line in Travel, you should have been able to
isolate it by using Hold. If you still had a leaky line, then the line
that was leaking was the main line from the control valve to the bag,
and it would leak no matter what mode. In a case like that, remove the
line at the bag, install a Shrader valve (which is one minute of work
with the right open-end wrenches), and then use a portable fill hose
connected to the tank to fill the bag. When the tank pressure drops
down, the pump will come on. If your pump runs only when the ignition
is on, then start up the 455 before pumping up the bag. The pump runs
better with 13.6 volts of the alternator rather than the 12 volts of
the battery when not being charged.

If you hang a hose quick-release fitting off the end of a steel pipe
TEE, then you can put a drain valve on the stem of the TEE and still
be able to drain water from the tank. So, pull the drain cock out of
the drain fitting. Screw in a steel TEE, and then screw in a hose
quick-release to the TEE. Then, screw the drain cock into the
remaining opening on the TEE.

Rick "who suggests steel TEE fittings for fatique resistance" Denney

'73 230 Ex-Glacier "Jaws"
Northern Virginia

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> Is it a good idea to tap off of the bottom of the tank? Won't you get all of the moisture that collects there?
> Ray Erspamer
> 78 Royale - Malosco Cruiser (TZE368V101144)
> 2202 N 115th St
> Wauwatosa, Wisconsin 53226
> 78GMC-Royale
> 414-745-3188
> Web Site: http://www.angelfire.com/planet/raysgmc/
>

> > Not to the pump, but to the tank.

Yes. That is the other thing this fitting is for, draining. I can also fill the system from that point.
"if it needs it"

--
Hardie Johnson "Crashj"
1973 26 foot Glacier, White Thing
Raleigh NC

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> The pressure switch on the pump measures tank pressure. So, if you
> bleed air out of the tank with the valves in Hold, the pump will turn
> on when the tank pressure falls below the lower threshold on the
> pressure switch.

I don't know if there's a difference between the Electro-Level I system (which I have) and the Power-Level system (which you have), or if my system is just out of whack, but when my system is on Hold the pressure switch does not operate. It only activates when the tank pressure drops below 95 psi while on Travel. I suppose when accessing air through the quick-connect I could set the system to Travel and set the leaky side to Lower so it would not call for air to that side. Then the leveling valve would close on the non-leaky side and my quick-connect would have the tank and pump all to itself.
--
Nick Chapekis
Ypsilanti, MI
78 Kingsley

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> Since the instruction calls for measuring from the top of the slot to
> th ground, we did a simple measurment and cut. Rear is about 8 1/2 " long, front about 9 1/2"
>

OKAY, but do you want to crawl under there every trip? :lol:
I had a stick which was marked for the various conditions including leveling left to right in the driveway. I measured at the top of the beltline and a discreet mark on the front bumper.
"lost the stick, marks faded - maintenance is never-ending"
--
Hardie Johnson "Crashj"
1973 26 foot Glacier, White Thing
Raleigh NC

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th ground, we did a simple measurment and cut. Rear is about 8 1/2 " long, front about 9 1/2"


>
>

> > George, Your doing it right. Air pressure does no relate directly to correct height. At our shop we use a stick with the correct height to check.
> > Quote:

> > > > Before starting a trip,I adjust my air bags to the correct ride height, sitting flat with a normal load of passengers, water and gas.
> > > > --
> > > > geo groth '73 260 Sequoia
> > > > Carson City Nevada
> >
> > --
> > Jim Kanomata
> > Applied/GMC
> > mailto:jimk
> > 1-800-752-7502
>
> Yabbut, flat is not exactly right, if you mean level floor. The coach should sit slightly tail-dragger. You can set the stick to measure at the beltline or taillight, but check the front bumper, too.
> "not to self, make a new stick to replace the one left in Enola"
>
> --
> Hardie Johnson "Crashj"
> 1973 26 foot Glacier, White Thing
> Raleigh NC

Hardie, I did mean a level floor, not a flat coach environment; of course, the front ride height should be set by adjusting the torsion bars with the correct tool. The rear should be at the correct height when doing this as well. It takes some going back and forth to get it all adjusted front to rear and side to side. I always measure from the correct slots and don't try to adjust to bumper height or anything else. I think anyone interested should search for the doc on "Setting ride height".

--
geo groth '73 260 Sequoia
Carson City Nevada

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> We likewise have a SPDT switch to our Dana pumpI keep saying I am going to add a hefty relay into the circuit so this 15amp rated sw. stops getting so darn hot! So my question Hardie, you just using a switch or a switch and a relay or did you find a sw rated higher than 15amp?

I have a switch from a headlight/foglight setup. The switch is illuminated and has a center OFF position as well as connecting house or chassis to the compressor. It probably should have a relay at the Viair compressor. It is fused, anyway.
"adding to todo list"

--
Hardie Johnson "Crashj"
1973 26 foot Glacier, White Thing
Raleigh NC

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> We likewise have a SPDT switch to our Dana pump for normal engine
> ignition on only or direct to engine battery for when engine is off if
> needed. I keep saying I am going to add a hefty relay into the
> circuit so this 15amp rated sw. stops getting so darn hot! I've tried
> 3-4 different switches but none are hefty enough to not get good and
> warm/hot when compressor runs for a while. So my question Hardie, you
> just using a switch or a switch and a relay or did you find a sw rated
> higher than 15amp?
>
>
>>> That'll be easy enough. Once I access the air, though, how do I run the pump independent of the system?
>>>
>>
>> That is a good point. Ihave my compressor wired to run off of either house or chassis battery. Normally I just leave it in HOUSE. With the air hose connected, the compressor kicks in whenever I use air from the tank.
>>
>> --
>> Hardie


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