Interior and Upholstery Power lumbar questions

[7991LXnSHO]

I hope I do not already know the answers to this problem. When I had the seats recovered, I had the driver’s seat leaking lumbar bag (heavy rubber) replaced with a new Ford part with the same number (a plastic bag!) It did not work for very long. The pump still sounds like it is working, but nothing inflates. I plan on testing the pump’s output and seeing if the bag inflates from the line with a low psi air hose nozzle.
If it’s the new plastic air bag -
1. Is the HD black bag available new?
2. Should I try to patch the original bag with a tire/tube patch?
3. Do the top seat covers do not clip together at the bottom, Velcro or zip like my newer Fords, so there’s going to be sewing involved to get to this?

 

[Mustang5L5]

#1) Nope. Got a pic? Might be similar to the SN95 seat bags which can be possibly substituted.

#2) I'd try to find a replacement first, then patch as last resort. Fill it and submerge it and find the leak.

#3) There is either a zipper or J-channel clip at the bottom. Very easy to disassemble and reassemble the seat. No need to sew, unless the upholstery did something weird

 

[7991LXnSHO]

Thanks for the SN95 suggestion. As hard as the replacement bag was to find 5 years a ago, I was thinking I was at the last resort stage.
The other answers were exactly as I hoped or feared they would be.
As it snowed two weeks ago, I had the car parked off site, and could not look at the seat backs. I will get a pic and measurements of the stock bag and be back about this. We are still figuring out where stuff is after a move. I hope the part number is still readable.

 

[Mustang5L5]

I’ve got an SN95 bag handy that I was planning to retrofit into my Recaro seat. I can measure off it to compare if needed

 

[stormsedge]

Go slow as you take it apart. The lumbar "bag" in my 2K GT had slipped its clips and pushed down lower into the seat back making it appear as if it did not work. I put it back in place and cobbled up new restraints/mounts to hold it in place...problem solved. If this your case, be sure to have the bag inflated or leave room for it to inflate correctly when securing it back in the seat. Cheers!

 

[Mustang5L5]

Thus us what a 99-04 bag looks like