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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Bob Belter on September 16, 2012, 01:47:01 PM

Title: Air Beam volume
Post by: Bob Belter on September 16, 2012, 01:47:01 PM
Ahoy, BusFolk,
I am installing some air bags on a Ford E450 6.0 Diesel cutaway chassis (ex ambulance).  I plan to add an additional volume air chamber on each side rear, to reduce the spring rate.  The air bags are the double doughnut style.  I will be incorporating suspension mods --  traction bars --  and fewer springs.

The GM 4104 used similar --  larger  --  air bags, and an air beam for greater air volume. Does anyone have any idea of the volume of the air beam in the 4106, and the air bag diameter.  Such knowledge would be a good start for me to achieve a similar air bag to air beam volume ratio.
Incidentally, I'll be mounting a GMC motor home 'hull' (the 23' three axle front wheel drive -w- the Toronado power train) on the Ford, to supplement my -01 Eagle.  Interesting note --  the Olds  Toronado is so extinct that it is not in my spell checker.
Thanks    /s/    Bob
Title: Re: Air Beam volume
Post by: RJ on September 16, 2012, 04:03:00 PM
Bob -

The 4104 used double convoluted air bellows with the air beams.  Dunno if there's any published data on how much air the beams held, but it might be determined by dimensions listed in the parts book, if there's an exploded pic.  My '04 parts book is packed in storage at the moment, otherwise I'd look for you.

The 4106 and all later GMCs use rolling lobe-style, eliminating the air beams which were prone to developing pin hole leaks.

IIRC, the passageway between the air bellows and air beam on the '04s is pretty large, about 3" - 4" in diameter, maybe larger.  Might make it hard to get the correct air flow characteristics using separate air tanks?

Trying to envision what you're doing w/ the Ford chassis and GMC Motorhome hull. . . Are you grafting the two together by cutting off the front end of the hull (say behind the front wheels) and mating that to the cutaway cab?

FWIW & HTH...

;)
Title: Re: Air Beam volume
Post by: luvrbus on September 16, 2012, 04:10:25 PM
Hey mate I read somewhere in a MCI  manual it was 2-1/2 times the air bag capacity,what the hell are you making Bob I thought you were going to sell the Eagle and kick back 

good luck
Title: Re: Air Beam volume
Post by: gus on September 16, 2012, 04:52:09 PM
The volume probably makes little difference. When I capped only one rear side of my 4104 it made no difference whatsoever except the suspension aired up faster.
Title: Re: Air Beam volume
Post by: Bob Belter on September 16, 2012, 06:49:05 PM
Ahoy, BusFolk,

I'm installing a GMC '23' hull on my Ford E450 chassis.  Sliced-off at the entry door, the hull it is very close to 16'.  Enough room for a SFF Motor Home --  read 'Short Fat Fellow'.  Total length is ~~ 24'  -- AND I will have a modern economical turbo diesel SFF machine, albeit a bit taller than the original.

This Ford sucker is the most violent/brutal ride  I have ever seen, hence the suspension mods.  I suspect that the ambulance patients arrive dead --  shaken to death.

Yuh, My -01 Eagle/Cummins M-11  it will be for sale in the future, but not quite yet
 
The Ford E450 'Cutaway - Van Cab Chassis' is the best kept secret in the world.  I got this E450 /6.0 Diesel for $3,000.  I'd seen one go for $2250 some months before.  These companies pull the ambulance 'box', refurbish it, and put it on a new chassis, and sell the old vehicle (2006).  These ambulances are very well cared for, so are in nice shape.  The one I got is near pristine.

Enjoy   /s/    Bob
Title: Re: Air Beam volume
Post by: Len Silva on September 17, 2012, 06:55:04 AM
I hesitate to pose such an obvious question but.....are you sure this chassis rode all that bad when it was loaded with the ambulance body?

A good spring shop may be able to tune the suspension to the load and give a very nice ride.
Title: Re: Air Beam volume
Post by: gus on September 17, 2012, 03:35:07 PM
Those ambulance bodies are heavy, probably much heavier than the GM body.
Title: Re: Air Beam volume
Post by: stevet903 on September 17, 2012, 05:53:49 PM
Here's a link to some pre-made springs with different capacities if you decide to go with a different spring instead of airbags... 

http://www.thesuspensionking.com/catalog/tables/ford_f450_f550.php (http://www.thesuspensionking.com/catalog/tables/ford_f450_f550.php)

Steve
Title: Re: Air Beam volume
Post by: Ed Brenner on September 17, 2012, 08:36:40 PM
Bob, how much do you know about the 6.0 Ford diesel. It doesn't have a very good history. Has a big problem
with the EGR system, blown head gaskets and broken head bolts. My neighbor and his brother who are heavy equipment mechanics have replaced or repaired at least six truck 6.0 this year. Ford didn't keep it around to long .

ED
Title: Re: Air Beam volume
Post by: luvrbus on September 17, 2012, 08:45:18 PM
  You have to remove the cab to change a turbo on 6.0 in a pickup a van maybe different
Title: Re: Air Beam volume
Post by: John316 on September 18, 2012, 08:22:05 AM
We had a 2004 6.0 E350 that we sold when the vehicle service contract ran out on it at 100k. You couldn't change the fuel filter on it without special tools (read dealer only, for the most part). Some dealers would actually jack the body off of the frame to work on that engine, things were so tight in there.

That is when we got a bus. Bus is more expensive ;D :D ;D

Enjoy. Sounds like a fun project that you have going.

John
Title: Re: Air Beam volume
Post by: Bob Belter on September 19, 2012, 03:33:41 AM
Ahoy, BusFolks,

Yuh, the Ford 6.0 Diesel does have a lousy reputation which is well deserved.  Problems onset are due to the orange Ford coolant which plugs things, including the oil cooler/EGR cooler.  I have an excellent article which I downloaded on what to do to make it a good engine, albeit still hard to work on in the van.   Off-subject for this web site so I won't post it, but I can send it to anyone who wants it.

Enjoy   /s/    Bob
Title: Re: Air Beam volume
Post by: lostagain on September 21, 2012, 07:53:04 AM
The 6L Powerstroke is an excellent engine with lots of torque for towing. You have to do an EGR delete and upgrade the head bolts, then it is bullet proof.

Luvrbus, you don't have to lift the cab to change the turbo. It just lifts off the top of the engine.

JC
Title: Re: Air Beam volume
Post by: TomC on September 21, 2012, 08:16:09 AM
There are two types of air bags-double or triple convoluting and rolling lobe. The convoluting are very reactive and by themselves ride harshly.  Hence on the 4104, they use air beams to soften the ride, or like on my AMGeneral transit, has what looks like big aluminum cans on the top of the double convoluting air bags.  Rolling lobes are usually larger bags that have a "piston" on the rolling portion of the bag that acts like a variable weight control-or better ride.  On my bus, either the double convoluting air bag with aluminum reservoir or the straight rolling lobe was available.  According to my bus mechanic, the ride was the same.

If you want to add more air space to soften the ride, don't even bother with the air beams.  Use an air tank with 1" hoses in line with the air bags.  These are commonly called a ping tank.  Will soften the ride and will much simpler then the air beam.  Freightliner uses the ping tanks on M2's and with SportChassis.  They work very well.  Good Luck, TomC
Title: Re: Air Beam volume
Post by: gus on September 21, 2012, 04:13:06 PM
My 4107 has straight rolling lobe air bags, the 4104 has convoluted. Believe me, the better ride of the 4107 is astounding - absolutely no comparison.