ISRI Parts

[phorner]

I have found one of my aux air leaks and it looks like I need to replace the switch console for the air lumbar support.

Any ideas where I might find a replacement?

[JIM CHALOUPKA]

Paul, Rogers solution to the lumbar air leak on my bus was to block it out of the system.

I find nothing negative about this.

Another way to address the leak and retain control of the lumbar support, would be to install a mini valve in the line just before the leaking switch and apply air to make an adjustment only.


JIM

[Ray Davis]

Paul,

How did you go about trouble-shooting your leak in your seat. During my OKC trip, I developed a leak in mine too (I think). I haven't yet tried to track it down, but the hiss while driving is definitely annoying.

How did you go about tracking it down the leak?

Thanks,
Ray

ps: I hope your front window is still leak free! :D

[jack14r]

I think I remember seeing the ISRI seat in the Prevost parts book.

[phorner]

Ray,

I borrowed an electronic stethoscope from Truk and the first place I suspected a leak paid off. You could clearly hear the difference from one switch to the other.

I confirmed with a spray of the Big Blue leak detection solution, and the bubbles were quite significant. There is a leak at the connection of the inlet air line and another internal to the switch.

These very small air lines and fittings are subjected to 120+ psi, so a small leak shows up fast.

Oh, and the windshield is still good to go :D

[Ray Davis]

I gotta get a stethoscope! Maybe I'll try locating one of those ultra-sonic leak detectors.

Glad to hear the window is doing good! Phew! :p

[Alek&Lucia]

Tom,

Which model of the electronic stethoscope do you have ?

Alek

[phorner]

Paul, Rogers solution to the lumbar air leak on my bus was to block it out of the system.

I find nothing negative about this.

Another way to address the leak and retain control of the lumbar support, would be to install a mini valve in the line just before the leaking switch and apply air to make an adjustment only.


JIM

Jim,

If I decide to plug this line off, what would you recommend? It's a very small inlet air line, maybe 1/16" ID or so.

And, it needs to seal against substantial pressure....

[Danss]

Parliament coach replaced my switch because of same leak.

[truk4u]

Alek - I'll have to refer you to Paul, I don't remember the name. It wasn't expensive, I think around 75 bucks and they work great. I had to buy Brian E one before he would deliver my bus!

Paul - I replaced the ISRI switch assembly on the Marathon I had and then it started leaking. Very expensive stuff and they suck! Got it from Prevost.

[Orren Zook]

On my seat the fittings have 1/8" pipe thread, and 1/4" nylon tubing supplying the air.

[phorner]

The air lines to my lumbar controls are much smaller diameter, with the inlet air line being very small, probably 1/16" ID or maybe even 1mm.

The outlet lines to the upper and lower lumbar bladders are larger diameter, perhaps 1/8" are are a barbed style connection.

[campers]

Paul,
Go to Suburban Auto Seat Company, Inc.
( www.Suburbanseats.com )
Did replace my lumber valves and they charged me $ 68.00 for the valve.
Replaced it by myself.
The valve comes with the plastic pressure lines.

[phorner]

Thanks. I'll give them a call too....

[grantracy]

just bought a replacement from Prevost

[jimshoen]

The air control switch on the ISRI are known to leak. The replacement switch can be purchased from Prevost, that is what I did. Also, the bag in the seat back which is the upper and lower lumbar support can develope leaks. Mine leaked and I replaced that also. Can buy the bag from Prevost also. Now it all works real well.

[phorner]

OK, so I decided to order up the replacement switch from Prevost and take care of this pesky leak.

The replacement "kit" arrived and included a new switch assembly with the inlet air line and two outlet air lines attached, a new switch housing and some miscellaneous attachment pieces. Since the new switch came from the factory with the air lines attached, I was real reluctant to remove the inlet line, as I assumed that it was sealed real good and may have even been pressure tested. In order to retain that original connection, it meant pulling the seat out, as the inlet air line attaches to a tee located under the seat.

So, I removed the CB as it was in my way, disconnected and removed the electric seat adjustment switch, and proceeded to pull the drivers seat out.

Found the tee and connected the new air line using a sort of compression fitting. The down side to this approach was that if I created a leak here, it would be buried under the seat.

Fired up the compressor, tested for leaks and NO LEAKS!!!

So, I put everything back together ..... only to discover that I hadn't passed the new air inlet line through the switch housing first!!! AAAHHHHHH:eek:

Well, I had a choice to make... try to disconnect the inlet air line at the switch and hope that I can get it back together without leaking or....pull the seat back out and start all over.

So, I got to do it all over again.....:o

And still no leaks!!!:D

This helped considerably with the cycling of my aux air compressor, but has not restored it to a once-a-day event as I would like it to be.

[Jon Wehrenberg]

Paul,

On your Liberty there is a six air line manifold in the steer compartment.

That manifold is where Liberty distributes aux air to all of its house devices such as the bed lift, the seat, generator air bags, dump valves, etc. If you plug them one at a time and measure the impact it has on your aux compressor cycle time you will know where to look for the leak(s).

Or you could spend countless hours and install shut off valves (like I did) to make the job of shutting off the various air circuits easier.
Of course now I have about 15 more joints which could potentially leak.

[phorner]

Thanks, Jon.

Sounds like a good plan.....