Sticky or Best Thread for Air Supsension Diagnostics?
#22
Ride height can be set using the Jaguar software that dealer should have. The height sensor sends a signal, but this has to be related to the actual physical height. What one does is measure the actual height and enter this into the system so that it has a reference value. The system should then be able to set the correct height.It is a routine operation, nothing really special. I would think all cars with air suspension like Land Rover, Mercedes, etc will have similar maintenance routines.
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Don B (10-08-2017)
#23
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It's not too difficult to replace the front air spring/shock absorber units as long as you're prepared with the correct tools. Arnott Industries has instructions in pdf and video formats:
Arnott Industries Jaguar X350 Front Coil Conversion Instruction Manual PDF Download
Their instructions make it look easy to disconnect the upper control arm ball joint, but you may have to hit the flat strike point on the steering knuckle/vertical link with a hammer to get the ball joint to separate. Loosen, but do not remove the ball joint nut so the steering knuckle can't suddenly fall on you when the ball joint taper comes free.
The lower shock absorber bolts require a large Torx bit, size T60, and some owners have found them to be exceptionally tight and difficult to remove, so have a long breaker bar on hand, and a couple of short extensions (3" and 6"?) in case you need them to clear obstructions to get your Torx bit on the bolt and have your breaker bar free to move.
The Arnott instructions state to remove all four top nuts at the same time, but I recommend loosening all of them but removing only two until you are ready to lower the entire unit. This provides a measure of safety against the heavy unit falling or shifting and smashing your fingers when you remove the lower bolt. Once you're ready for removal, you can support the unit with one hand and remove the remaining two top nuts with your other hand, then use both hands to withdraw the unit.
When you reinstall the new units, as you are working the top studs into the holes in the suspension tower, pay attention to the orientation of the lower shock bushing to be sure it will align with the control arm. Hand thread a couple of nuts on top studs to hold the unit while you get the lower shock bolt started and threaded most of the way in.
Having proper torque wrenches will save you a lot of headaches, because the biggest mistakes folks tend to make are to overtighten things like the air spring top nuts, ball joint nuts, etc. Don't do it! The factory torque is enough.
You won't be able to use your torque wrench on the air hose fittings, and lots of owners have caused problems by overtightening them. My best advice is to tighten them as far as you can by hand, then just snug them up with a wrench. It doesn't take much force to seal things up.
This would be a great time to replace some of the other suspension components if you are prepared to do so, such as the upper control arms, lower control arm bushings, etc., but at the very least it would be a great time to replace the boots on the upper control arm ball joints, which are inexpensive from eBay sellers.
Cheers,
Don
Arnott Industries Jaguar X350 Front Coil Conversion Instruction Manual PDF Download
Their instructions make it look easy to disconnect the upper control arm ball joint, but you may have to hit the flat strike point on the steering knuckle/vertical link with a hammer to get the ball joint to separate. Loosen, but do not remove the ball joint nut so the steering knuckle can't suddenly fall on you when the ball joint taper comes free.
The lower shock absorber bolts require a large Torx bit, size T60, and some owners have found them to be exceptionally tight and difficult to remove, so have a long breaker bar on hand, and a couple of short extensions (3" and 6"?) in case you need them to clear obstructions to get your Torx bit on the bolt and have your breaker bar free to move.
The Arnott instructions state to remove all four top nuts at the same time, but I recommend loosening all of them but removing only two until you are ready to lower the entire unit. This provides a measure of safety against the heavy unit falling or shifting and smashing your fingers when you remove the lower bolt. Once you're ready for removal, you can support the unit with one hand and remove the remaining two top nuts with your other hand, then use both hands to withdraw the unit.
When you reinstall the new units, as you are working the top studs into the holes in the suspension tower, pay attention to the orientation of the lower shock bushing to be sure it will align with the control arm. Hand thread a couple of nuts on top studs to hold the unit while you get the lower shock bolt started and threaded most of the way in.
Having proper torque wrenches will save you a lot of headaches, because the biggest mistakes folks tend to make are to overtighten things like the air spring top nuts, ball joint nuts, etc. Don't do it! The factory torque is enough.
You won't be able to use your torque wrench on the air hose fittings, and lots of owners have caused problems by overtightening them. My best advice is to tighten them as far as you can by hand, then just snug them up with a wrench. It doesn't take much force to seal things up.
This would be a great time to replace some of the other suspension components if you are prepared to do so, such as the upper control arms, lower control arm bushings, etc., but at the very least it would be a great time to replace the boots on the upper control arm ball joints, which are inexpensive from eBay sellers.
Cheers,
Don
Last edited by Don B; 10-08-2017 at 09:56 PM.
#24
TucsonDave,
Please forgive my stupidity, but when you say 'I disconnected the air hose at the top of the strut, screwed on the cap tightly, which made for an air-tight seal. I then started the car, pressurized the system, and it didn't leak, so I know I need a new right side strut'.
Which strut did you disconnect?
'It didn't leak' - What did not leak...The hose? The disconnected strut? Which strut?
How did you know that it was the right side strut you needed fixing?
TucsonDave, again, the answers to my questions are probably obvious - But I cannot see them!
Please forgive my stupidity, but when you say 'I disconnected the air hose at the top of the strut, screwed on the cap tightly, which made for an air-tight seal. I then started the car, pressurized the system, and it didn't leak, so I know I need a new right side strut'.
Which strut did you disconnect?
'It didn't leak' - What did not leak...The hose? The disconnected strut? Which strut?
How did you know that it was the right side strut you needed fixing?
TucsonDave, again, the answers to my questions are probably obvious - But I cannot see them!
Last edited by EsRay; 11-21-2018 at 09:44 AM.
#25
#26
Thanks Wingrider.
Okay, I think I get it (maybe)! Please correct me if I am wrong....
When I deploy Tucson Dave's ingenious use of a domestic plumbing line cap, does the shock I release immediately deflate? Will the height sensor then detect this and lower the other shock to match it? Then, when I re-pressurise the system the 'cap' will fool it into thinking that the capped shock is fully inflated and accordingly, it will raise the other shock? Which do you think I should try first; the shock on the height sensor side or the other?
Perhaps I still don't get it!
Okay, I think I get it (maybe)! Please correct me if I am wrong....
When I deploy Tucson Dave's ingenious use of a domestic plumbing line cap, does the shock I release immediately deflate? Will the height sensor then detect this and lower the other shock to match it? Then, when I re-pressurise the system the 'cap' will fool it into thinking that the capped shock is fully inflated and accordingly, it will raise the other shock? Which do you think I should try first; the shock on the height sensor side or the other?
Perhaps I still don't get it!
#27
If the system fills with air, then holds pressure, you have found your leak.
It is possible to have more than one, if you think so, get another, or move it, as you may have missed your guess.
Jaguar specific type readers, icarsoft as well as several others, will tell you which shock is malfunctioning.
Having the right tools seems to simplify things to the maximum, making things much more pleasant to do.
Garage, much like the barn in the past, is where your tools, the basic type things to survive, & where your money was invested.
Seems as far as material wealth, ALMOST ALL mine is in there, and i am what is considered lower than middle class, making me poor.
But i'm very RICH with all god promised and so much more!!!!!!
Because where i have lived for more than 40 years, neighbors say HE CAN FIX ANYTHING, tell you how, has the special tool to make it easier, or who can.
That is something that feels great to be able to give away to people.
Because, WWG1WGA
It is possible to have more than one, if you think so, get another, or move it, as you may have missed your guess.
Jaguar specific type readers, icarsoft as well as several others, will tell you which shock is malfunctioning.
Having the right tools seems to simplify things to the maximum, making things much more pleasant to do.
Garage, much like the barn in the past, is where your tools, the basic type things to survive, & where your money was invested.
Seems as far as material wealth, ALMOST ALL mine is in there, and i am what is considered lower than middle class, making me poor.
But i'm very RICH with all god promised and so much more!!!!!!
Because where i have lived for more than 40 years, neighbors say HE CAN FIX ANYTHING, tell you how, has the special tool to make it easier, or who can.
That is something that feels great to be able to give away to people.
Because, WWG1WGA
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#28
#29
#30
Same reader, Launch makes a fine unit, but is not Jaguar specific in its functions, library section seems a bit better.
My i930 was last years model when purchased, but got a bunch of old readings of faults, from before as well as after purchase.
Thats how i know about reading suspension codes, had already fixed my compressor, and installed new shocks, before getting the i930.
My i930 was last years model when purchased, but got a bunch of old readings of faults, from before as well as after purchase.
Thats how i know about reading suspension codes, had already fixed my compressor, and installed new shocks, before getting the i930.
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EsRay (11-24-2018)
#32
#33
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My recollection is that the front air spring hose fittings are 1/8 inch BSP (British Standard Pipe) thread, which has an external thread diameter of 9.6 mm or 0.38 inch (just slightly larger than 3/8 inch). The front air hoses are 6 mm O.D.
The rear air spring hoses are 4 mm O.D. and the fittings are a different size. I think one of our members figured out that they are 5/16 UNF ((British) Unified National Fine) thread fittings, but I may be wrong.
These are not sizes you are likely to find in stock in a hardware store in the U.S. However, I believe I ordered them from McMaster-Carr (mcmaster.com) to build pressure gauge test rigs based on lcmjaguar's design.
Cheers,
Don
The rear air spring hoses are 4 mm O.D. and the fittings are a different size. I think one of our members figured out that they are 5/16 UNF ((British) Unified National Fine) thread fittings, but I may be wrong.
These are not sizes you are likely to find in stock in a hardware store in the U.S. However, I believe I ordered them from McMaster-Carr (mcmaster.com) to build pressure gauge test rigs based on lcmjaguar's design.
Cheers,
Don
Last edited by Don B; 09-22-2021 at 06:44 PM.
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AD2014 (09-29-2021)
#34
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