P30 Air bags - front

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Sonny, quite right. The bags are the Firstone 4100 series that are on the rig.

I put them in in 2006. The original vendor said that he expected them to last 5-10 years.

Guess he was pretty close..  :)

Carson
 
Sonny, don't worry about the front axle weight.  Actual weight from a scale was about 5200 lbs. Those 4100 airbags are plenty strong at 50/60 lbs.
carson
 
JRickey said:
I changed mine last summer.  Never done it before and followed the instructions provided.  I bought mine at Camping World for around $75.  It took me no longer than 3 hrs.  I could probably cut the time by a third the next time (hope there isn't one).  It is a real pain in the butt.  It helped alot to soak them in hot water to soften up the ends.  I flattened them down to a spear looking thing with the ends poking out and then wrapped then with electrical tape.  The hardest thing is getting the rubber washers in place on the top and bottom.  There is no way it took someone 4 hours to do this that is experienced and compotent.  I think the time was inflated

Double that for me.  I did mine last year as well.  After a few hours, lots of bad words and the dang washers ta the top in line the job was finished.  Not fun at all but not technically challenging either.  Getting the bags through the small hole is the hardest.  2nd hardest is keeping the top washers in the proper alignment. 

No more porpoising of my rig.  The guy I got it from was out last week and took it for a spin.  He had no idea how much better the rig drove with the airbags.  He had it for a long time and never fixed them.  He did not think they would make much of a difference.  He said if he knew how much better it would drive he would have done it 10 years ago.
 
My air bags are about to go in. Had them (Firestones) for a couple of months now, but been dragging my feet. None of my jacks would get the front wheel(s) off the floor. I searched for a higher lift floor jack, but unable to find one used. Finally opted for a 12 ton air/hydraulic bottle jack. Setting it on blocks, it raises chassis enough to get the tire about 3" off the floor. Got one side raised and tire off. Supported by the jack and a good stand, I'm getting over the urge to sit and stare at it. Time to get under and dirty. Suggestions here are helpful. I did also purchase the splitter fitting to fill both at one time. It originally had separate air jacks. Now it will have only one. This is, IMO, better so that if one fails they both fail at the same time. Pressure will be equal at all times.
 
Got one old one out......not too bad, but the new one......no way I could flatten and twist that enough to make it fit in that hole. Takes more hands and muscles than I can muster. I took two 12VDC air compressors, one broken and the other one that I carry in the MH. Cut the hose nipple and hose from the broken one and, using JB Weld, glued it onto the air inlet of the other pump (after cleaning the metal, oc course). It works!!!! It sucked all the old air right out of the bag. The JB Weld is not quite hard yet, so I'll wait until tomorrow to see if I can get those things bound up enough to get them through the hole. I'm betting I can with all the bad air out.

Now I have a pump that blows and sucks.
 
I read that people who have soaked the new bags in really hot water with dish soap (heavy concentration of soap) have had good luck getting the new bag in. Straight from the water to through the hole.
 
My new sucker works great. Sucked them Flat. I then twisted and tied, squished and squeezed and tightened the zip ties as tight as possible. Still it is almost twice as big as the hole. I actually haven't tried pushing it through the hole, but I really have my doubts about getting something that big through such a small hole. I haven't measured the hole, but it is ~2" dia. Is that what they all are? Or is the hole smaller on my rig? I wonder about using my plasma cutter to enlarge it some. Looks like there is plenty of room to go bigger. HMMMMMM.
 
Gary RV Roamer said:
I think your hole is normal size!  [Did I really just type that?]  Everybody says it is a challenge to get that bag poked into the little hole, but it will in fact go.  I've never tried it myself, but have read several reports. Here are a couple:

http://www.rvforum.net/SMF_forum/index.php?topic=28512.0

http://www.rvforum.net/SMF_forum/index.php?topic=19038.0

Thanks, Gary. If others can do it, I can, too (I hope). When I look at the bundle of air bag, then look at the hole, it just looks like an impossible task. The zip ties that came with the kit were too short, so I bought longer ones...that helped. I could get a good hold on them to tighten them up. Maybe I can squeeze some more by adding a couple. The bags are Firestone 4100 and they seem heavier than what was in there originally. Maybe the old ones were just worn out.
 
It was a real fight, but I won. One side is in and so are the discs. Tomorrow I'll tackle the other side. Actually it went fairly smoothly after the first inch or so, then it stuck in the center. Twisting and pushing it went on until the last two inches. Then, without a place to grip, I was stymied. I tried the whole tool box to move it further, without success. Then I saw a hose clamp. Slipped in on the end of the protruding bag and tightened until the bag was small enough to go through the hole, then using a short piece of 2x4 I tapped on the end and it gradually went home.

To get the discs in place, I had to put some air pressure in the bag to straighten it out, relieve the pressure and pry the top down, slip in the top disc. The bottom was more difficult. I cut the air tube to it's proper length, pushed up through the bottom hole with a blunt stick, then slipped the disc in. Then I put more pressure in the bag to make sure everything was in place.
 
The other side (passengers) was much harder than the drivers side. But I did find, after two brusied elbows, several bashed knuckles and a couple of hours of battling both the bag and the discs, an easier way. I got the bag in about half way and could go no further. After an hour or two, I gave up. Finally decided that I need to go the hose clamp route again.....it worked on the first bag, but that clamp wouldn't fit this bag (too small). Bought a clamp that ranged from 3" down to 1-3/4". It did the job. I placed the clamp around the bag about 1/2" below the hole and tightened it (not too tight) until the bag could be pushed up. When the clamp touched the bottom of the spring pad, I loosened it and moved it down about 1/2", tightened, pushed the bag up again and repeated until it was in. The last couple of inches I tapped in with a block of wood, as before.

Then came the discs. They slipped in relatively easy on the first bag, but this one was a real battle. Not sure why the difference. I pried the top of the bag down and pushed the top disc into place (after a long fight) only to have it slip out and into the "A" frame. Then, whiile trying to figure out how to retrieve it, I noticed a big rectangular hole in the frame near the "A" frame joints. Reaching through that hole, I was able to slip the top disc into place without any problems. The bottom disc was another matter. It was a fight from the start and I never found an easy way, but it finally went into place and the hard part of the job is done. All that remains is to connect the air lines. I'm thinking I will put an air gauge in the line somewhere for an easy check of bag condition.
 
Usually, Gary, that is right. However, in this case, I'm very frustrated, not satisfied. I finished connecting all the air lines and pressurized to 50#. It leaked. So much so that it was down to zero in ~10 seconds. I soaped the connections and pressurized again. No bubbles. So I pressurized to 70# and then I could hear the leak. Coming from the bag/elbow area at the left front wheel. Pushed all the connections again and one was not in all the way. I thought that was it. Pressurized again and it blew the line out of the bottom of the bag. I trimmed the end of the tube to make sure it was nice and square....pushed it into the bag again....pressurized again and same thing. Blew the line out of the bag. Now I'm really hot under the collar. After all the blood, sweat and tears (not to mention the bruises), I had a bad bag.

Or do I? Looking at the underside, I see the disc is centered nicely, but the bag inlet is off center. The disc is actually pushing on the release ring and I believe the disc is releasing the air line as the pressure increases. I tried re-centering the bag inlet in the disc, but it won't stay centered. I gave up for the day. I'll sleep on it. Maybe someone here has had the same problem and can offer a suggestion. Or maybe the elves will fix it while I sleep.

The old bags did not have that bottom disc at the bottom....only the top. It would take and act of Congress to get it out of there and we know that ain't gonna happen, so I'll hope to find another solution.
 
Not quite sure what part of what is touching but have you considered a razor blade knife and just cut away the part of ring that is touching.

I have changed both on my old SouthWind and YES they are a major PITA. Both times mine blew the day before a trip preflight check was to air up day before. Yes I was lazy and only changed the one that was leaking at the time there was 2 years in between each one leaking.
 
Don't know if they are fixed, or not. Put 50# in left them for an hour or so and checked pressure. 48#. This may be normal, since I lose a little air when checking and they may be stretching and settling in. Time will tell. Whew! What a job!
 
yeah thats sounds about right to me. mine were so hard to get to excatly 50 i don't think they ever were right.
 
They aren't that precise a device anyway. Nor is there an exact right number - you can adjust to suit your preference - more pressure means a stiffer ride but better ster handling, while lower pressure gives a softer ride.  I would go a bit over the minimum recommended pressure and try it out for awhile.
 
Just thought I'd post this for future readers of this thread. We developed a leak in on front air bag near the valve stem. We put Slime tire leak sealant in the bag to hold it until we could fix it. However it has held over 3 trips which included many miles on dirt roads as we tend to boondock in the national forest. One day the bag may need to be replaced but in the mean time the Slime was a quick, easy, inexpensive fix. We have tire pressure monitor sensors on them so it is easy for me to check them each time we take a trip and so far no air loss.

Michelle
 
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