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Argh - Air suspension...


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I know, many of you told me to convert the whole mess to conventional suspension... Perhaps it would have been better. But OK, I'm working on it, so perhaps there's possible help. The conversion would be the last escape, starting on monday if there's no other possibility.

 

I have three used rear air struts here, all of them are leaking air. One of it has a breach in the diaphragm, about 0.3 or 0.4 inch long, from which it's definitely leaking air, I checked this with soap water. The two others are also leaking, but I don't really know where. I guess it's also somewhere in the diaphragm. These two were installed in the car I drove around, there is a continous loss, but it's so few that the car raised itself and stayed raised when driving. But as soon as the car stands for about 10 minutes, all air left the struts.

 

There rust on the struts, I will remove it and coat the strut(s) so that the diaphragm won't get damaged too soon...

 

So, is there a chance to repair this breach(es)? I read somewhere (I guess it was on xt6.net(?) that this tool to repair damaged tyres (in spray cans) could also repair these damaged diaphragms? Will this last long? And how to connect these cans to the air struts? Some kind of adaptor will be necessary, but how and what?

 

Yeah, many questions... I'm a bit frustrated right know :( Please some opinions and hints on that!

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IMHO, toss em and go to conventional.

I dont know if you can repair a rip that big in the diaphram or not, none of them sound like they are in any condition to last much longer. Do the swap and quit worrying about wether they will stay aired up or not.

Last week I drove on flat air suspesion for 50mi. This was my beginning of a 6,ooomi journey. I almost turned around and went home (to get my RX).

But it decided to be nice to me and air up. Still havent attempted any troubleshooting....yet.

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fix-a-flat type sealant can work. i also know of someone that used an aircraft grade rubber/flexible sealant that worked as well. he covered the entire air bag with it, making it particularly thick at the leak. he was an airplace mechanic. i have a tube of the stuff at home and could give you the name of it, but i'm betting you can't get it there. i'm sure the airports have something similar though.

 

if you have 2 others, i would try to find out where they are leaking from. they may not be leaking from the bags.

 

you should be able to hook the rear struts up to any airline on the vehicle and have it pump them up, then disconnect them once they're full. since the solenoid is integrated to the strut you can disconnect the lines without pressure being released. so air them up and find the leakage points. you'll want to air up any strut you get anyway so you can clean them and paint them. you don't even need to install the strut...just hold it in your hand and hook up any air line to it. you could use one of the front air lines since they are accessible from the engine bay. install on the strut, open the solenoid and have the compressor air it up. never dnoe it, but i know it can be done.fijje

 

can you post a picture of the leaks? of the one i sent you? that was a good strut. was the package damaged at all when you received it?

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if you have 2 others, i would try to find out where they are leaking from. they may not be leaking from the bags.

What could be another leak? Through the rust? These struts are my used ones from the car, as I said, the leakage is so small on both that the car stays in a raised position and the compressor isn't runnig all the time. This is the case for several months now...

 

I couldn't test them until monday since I'm on an excursion tomorrow... If it's not the diaphragma and it's repairable, what's the best possibility to protect the diaphragma?

 

can you post a picture of the leaks? of the one i sent you? that was a good strut. was the package damaged at all when you received it?

Sure, I attached two images. The breach is located inside the red circle. A bit hard to see, but I couldn't manage to make a bigger picture since it's nearly dark outside. The package wasn't damaged, I didn't see the breach first, just today when I want to install it. I believe you that it was a good one, perhaps there was some rubbing in the packet on shipping? Don't know...

 

For the sealant: If I want to try this, I guess a good place to ask would be a tyre shop?

post-5803-136027623974_thumb.jpg

post-5803-13602762407_thumb.jpg

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how about an inner tube patch kit?

No personal experience here but wouldn't the pressure be a bit too high? maybe if you were able to patch it from the inside you might be OK (push the patch through the hole then hold it in place with a string while the glue sets) Just my thoughts though

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No personal experience here but wouldn't the pressure be a bit too high? maybe if you were able to patch it from the inside you might be OK (push the patch through the hole then hold it in place with a string while the glue sets) Just my thoughts though

 

i dunno whats the factory pressure set at? i know its worth trying at least

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Hmm, it seems that most Germans are much too non-creative and don't know how to improvise something for such a problem: I was at several stores and garages today, including Bosch and MAN and I don't get any real idea besides "we haven't done any similar yet" [oh, come on, you're kidding :rolleyes: ] and "air bags need to be changed if they are damaged" [oh, that's really something new to me :rolleyes: ].

 

Anyway, I need that car in a few days, so I will convert it temporally to conventional suspension tomorrow, then I have time to work on the air suspension and search for a solution (there must be one, I have to call some sealant manufactures).

 

But thanks for all your suggestions!!

 

Another question: Since I'm a bit worried that the front brake hoses won't loose and because the front suspension still works, I'm thinking of doing the conversion in the rear only. Is there a easy way to make the air suspension control unit think that the rear struts are still there and that the ride height is OK? So the front suspension should work normal... If it's too complicated, I will change the front, too, but it would be much less work.

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that one you showed a picture of, is that one i sent you? i would attempt to repair that, it doesn't appear significantly dry rotted and doesn't appear to be close to the ends that will be curled under and stressed at the bottom. if i remember i'll look at the name of that aircraft grade sealant and post it tomorrow. know any small airports, airplane mechanic places close to you, they may have something similar? i'm not surprised with the answers you've gotten so far, noone over here would mess with them either. they also have heavy duty repair kits for rubber rafts that may be useable. some people at XT6.net (unfortuantely the site is donw now) know the pressures the system operates at. actually it's proably in the FSM i'm sure. if you know that and know the rating of a rubber patch kit (like for inflatable rafts), i would consider going that route as well.

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Hard to find the info in the FSM, but I think its 10atm. Dont know what that translates to her offhand, but probably more useful to you in EU.

 

Any patch may have to be vulcanized (heated) to bond with the diaphram. Its possible a good professional tire patch kit would work.

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Yeah, it's an electric comprossor which kicks out at 137 psi according to the FSM. So the pressure in the air struts couldn't be higher than that... But 137 psi are not that less. Anyway, I will make an intensive search for repairing the air bags during the next weeks.

 

And I find out that bridging the black and blue wires of the reed switches should make the control unit think that the car is at low normal which seems to be ok. So, I will make the rear conversion tomorrow :) It should work fine.

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Som, the car is runnig again. Front air suspension is working normal, the rear is converted to conventional. I'm leaving in a few hours, so I have to pack all necessary things into the car... Time is ticking away :rolleyes:

 

:headbang::headbang:

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Keeping in mind this information is old, here is the information off aircraft grade sealant that i know someone used to repair leaky air struts. he was an airline mechanic.

Dyna Seal 11120 Sherman Way Sun Valley CA, 91353

Phone 818 982 1650

Dyna-Kit

 

Flamemaster Corp. Chem Seal Div

CS 3204 Sealing Compound

AM5-58802 Class B-2

1 CA 3.5 Fl Oz

Batch A 0002027

 

probably nearly impossible to get?

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