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Topic: Isolation valve O rings (Read 840 times) previous topic - next topic

Isolation valve O rings

When I replace the Haldex dryer I would like to service the isolation valve. I have read here it is easy to do and cheaper than buying a new one. I have also learned that special  O rings are needed. Where are these O rings sold? Cummins parts house? NAPA?
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.

Re: Isolation valve O rings

Reply #1 –
Just buy the kit then you get all the parts you need for the isolation valve.

DQ6020 by HALDEX - Lower Housing Repair Kit
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Isolation valve O rings

Reply #2 –
I'm going to get a remaunfactured unit, so the only thing I'll need is the o rings. .....  I think 🤔.      I need to replace it and I'm trying not to talk myself outta doing it myself
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.

Re: Isolation valve O rings

Reply #3 –
The last time I replaced our dryer, I installed a new isolation valve.  I figured I would take the old isolation valve apart, clean it up, and keep it for a spare.  Well, I could not get the sucker apart!  I used the biggest wrenches I had, applied extra leverage with a cheater pipe, used a propane torch to heat it...tried every trick I knew from working in the oilfield.  It would not come apart.  I finally gave up...it's still sitting there on my work bench, mocking me every time I look at it.

My advice: just buy a new one.

Haldex KN23500 N15842H N15842J Air Compressor Solenoid and Isolation Air...

Haldex Isolation Valve
1993 U280 SE 40' WTBI, Build: 4359
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Re: Isolation valve O rings

Reply #4 –
Here is another view

Re: Isolation valve O rings

Reply #5 –
To the best of my knowledge, neither of the two overhaul kits (both needed to do a complete overhaul of the dryer itself) include the isolation valve 'O' rings. I did a lot of searching for info on the Isolation valve when I had a failed air dryer in Canada. I couldn't get the parts and so was forced to have the air dryer rebuilt by a reputable company. I talked to their tech, and he had never heard of the isolation valve. I printed up information and sent him some links, but when I received the rebuilt air dryer and removed the piston on the isolation valve, I could see that different color 'O'rings had been installed. My research indicated that the 'O' rings needed to be of a particular material and said material was a certain color. So I suspect that the tech just went by size and replaced them with what he had on hand. Maybe they were fine, but when I got home I found new old stock isolation valves (Haldex KN23500) on eBay for a very reasonable price. As they seemed commonly available there, I have bought several and have a new spare ready to go. Here is a link to one eBay auction for the Haldex KN23500.
Attached also is a pdf of the Haldex instructions.
Don
Quote from: hdff –
I'm going to get a remaunfactured unit, so the only thing I'll need is the o rings. .....  I think 🤔.      I need to replace it and I'm trying not to talk myself outta doing it myself
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Isolation valve O rings

Reply #6 –
OK sounds like the best thing to do is just buy a new one and not mess with rebuilding the old one. Looking at all the research that I've done it looks fairly straightforward to replace it is there something I'm not seeing. I'm halfway mechanically inclined so I think I can do it but I'm just apprehensive to try.
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.
 

Re: Isolation valve O rings

Reply #7 –
Keith,

You have to have the mindset like this thing was put together by human hands (not like your transmission as it was built by magic) and you are a human so this is a DIY job. Look at it like this: it isn't but 4 hoses (that won't hook up but at one place) , 2 wires that run your heater, 4 bolts that mount the dryer, and the 3 pipe fitting that are on the isolation valve.  If you are somewhat mechanical there ain't nothing to it but do it. If you get stumped you have all of us here that will get you back on track.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."