Hello team.

2005 LR3, 159k miles.

I bought this a while back, super cheap, and just getting to look at it. The Suspension compressor ist kaput so I replaced it this afternoon. The Fault on the dash is now gone, the compressor kicks in and runs but a couple of problems and questions please:

1) There is a larger air hose on the pump. As you look at it mounted in place, it's the top right hand side. Is this the relief valve hose for the compressor? I ask because in removing the old compressor, it was a total bear getting this hose out. I basically had to cut the pump to pieces to get this hose disconnected. Now that I have it apart, I cant get it back in the new pump....

2) As noted above, the compressor now kicks on but its not raising the truck at all. It runs for minutes but is not raising the truck from the ground.

So - before I start replacing valve blocks and tracking down leaks, is that hose I cant connect a relief valve hose? Or is it part of what is missing to lift the truck up?
If its just a relief for the pump, where would you all recommend I start to look for problems on why the suspension wont budge (front nor back)?

Thank you.

 

1 - There are three larger hoses in the compressor area. One is JUST the rear HVAS drain if installed but people find it, see it and ask about it. The other two that go into the compressor are for intake/exhaust. Operating the compressor without either installed will mean a quick death as water and debris gets inside. The best method for these lines is to cut them in a straight section if they are hard to remove. Then you can just use a conversion kit that comes with couplers and new pipe ends. The exhaust line tends to melt into the fitting. The intake line always comes off pretty easily. But one also needs to understand how those push-connect fittings work, if a person pulls on them then they damage them. You have to push the line AND collet down together until the collect seats all the way. Then you only pull the line and it comes right out.

2 - It would be weird that it runs for minutes, it should error out LONG before that if they truck is not going up. That is because a pressure sensor monitors air pressure and if its not building it will kill the compressor and fault out.

But for the sake of repairing, no, those intake and exhaust lines do not need to be hooked up. The compressor will sound louder but it will have zero impact on operation.

 

OK thanks for the reply so far! So yes, I should have mentioned that I understand how to remove the pipes and that procedure with the collets. Truly then your comment is the Exhaust pipe from the compressor had melted in to that port which is why it had to be cut out. I may try a little heat to the plastic to see about reforming it and if not then will cut and add an adaptor.

That said, since the compressor is on and pumping, what would you all check next since the bags are not inflating?

 

Well you have to have a leak, a big one. You should be able to hear it.

You can remove the output line from the dryer and feel if pressure is building at the connection. If not, then you may have an exhaust valve issue so its just dumping air straight back out the compressor. You can also feel for suction at the inlet line if you take it off. No suction would clearly mean a big issue internally with the compressor.

 

OK - So with the exhaust pipe not connected, the pump runs for a bit and then you here a big release of air (like an 18 wheeler) that makes a short but loud "hisss" noise.

I will try to get that line hooked up and see if that changes anything and then start listening for leaks. Thank you!

 

Thats a disco fart, its just extra loud. But its also good, cause that means its building pressure in the main gallery.

You may need to get codes.

If you have lift rods installed on the sensors, they need to be removed and the factory rods installed.

 

No lift rods, but Im installing them once I get this sorted.

I dont have a reader at this point that can pull these codes. May have to bite the bullet soon though....

 

Then just keep checking for leaks. If the bags are REALLY low on air, it can take a couple cycles to get it to raise. But by now you should be past that point. On the compressor is a large black canister, is the dryer. Its full of stuff to remove moisture form the air. If the end is plastic pay close attention to the area between the two lines. A crack can form there and cause. big leak. Even a new compressor can have a crack if its the cheap ones.