Pneumatic suspension won't work.

[ClassySoob]

Recently I purchased a 91' Legacy wagon for $400. Driving it down the road, the car bounces like a super ball. When i got it home I noticed the suspension was dead. If i hit the button, the light flashes and the air pump runs... but the suspension does not fill. Took the system apart and blew all the lines out. The pump puts out little air, is this normal? I'm new to the pneumatic suspension and could us a tip or two.

[wtdash]

Hi,

There's more info on this system on the Legacy Central website as well, http://bbs.legacycentral.org/, but essentially the bladders (?) don't hold air.

 

If you CAN even buy parts they're $$x$$, so plan on just replacing it w/stock suspension. If you need a lift, there are multiple posts online on LIFTing the 1st Gen ('90-'94) to match the '96-'99 Outback.

 

GL,

Td

[heartless]

yup, what wtdash said - the bladders on the struts are shot and they are ridiculously expensive - if you can even find them. It is cheaper and easier to just replace the air struts with standard struts & springs - I did it on my 90 Legacy LS. It rode fine. Just disconnect the air pump, cut the lines off, and done.

 

Or you could opt for the slightly taller version, but do a little research on which struts & springs to use for that. I did this on my 95 Legacy L using 98 Forester struts & springs - but 95 is slightly different than a 91...

[john in KY]

If all 4 corners are down, fair chance the compressor is worn out. Not too difficult to inflate the struts individually if you understand how that solenoid works for each strut. Use compressed air, inflate and watch to see if the strut stays  inflated. Very rare, almost unheard of for all 4 struts to leak down. 

 

Standard AWD Legacy struts are a direct swap but the air suspension is very nice when it works. 

[ClassySoob]

Yeah, when I blew out the lines, I also filled the struts individually, and they seemed to have held the air. Just the height control is not working.

[idosubaru]

simplest to swap to conventional legacy struts. 

 

if you can get them back to good condition i've had great luck with air suspension, they easily run the life of the car, can be cheap, and never need replaced.  they're certainly cheaper than buying all new struts for a car.

but getting them to that point is not easy.  they're hard to diagnose and have lots of leakage points.

 

two most common leakage points for air in my experience:

 

1.  check the bags and see if they leak. if they do replace with used ones - everyone throws them away so they're not worth much if you can find one.  the air bags will last the life of the car is reasonably taken care of and not rusty.  the rust at the bottom of the cylinder where it rubs against the air bag will wear the bags through.  you can extend the strut, clean the rust, and paint the strut body. 

 

2. the compressor lines - the base of the fittings can crack and leak or the lines themselves can need new orings (clean them up good while you're disassembling)

 

there are nearly 20 orings in the system and they don't often leak but tha's a lot of potential for leaks. 

5 at the drier, 1 at the compressor, 2 at each front strut solenoid, rear strut solenoids, and 2 or 3 on the air tank.  

ideally you replace all of those orings or as many as possible. 

 

the solenoids i think can get weak too internally, where they allow air to flow out of the strut - but if the system is sealed i'm not sure that should immediately result in deflation as the air should still be contained internally. 

 

you can also convert the struts to just take a regular tire chuck inflator and inflate them manually.  

[wtdash]

Scroll down to Section 4-1 HERE to see the FSM for the Pneumatic suspension.