Author |
Message |
greebly Samba Member
Joined: August 27, 2009 Posts: 966 Location: Here and now
|
Posted: Thu Jul 29, 2021 1:31 pm Post subject: Re: Rebuild...... 1990 Air Conditioning |
|
|
djkeev wrote: |
Anyway, I found the cold air on the back of my neck to be rather annoying.
Dave |
I had my wife make me a Laibach hat In black. I look like a negative grand wizard when picking up groceries but I don't care.
Laibach https://www.youtube.com/watch?v=EavTye99eZA |
|
Back to top |
|
|
djkeev Samba Moderator
Joined: September 30, 2007 Posts: 32584 Location: Reading Pennsylvania
|
|
Back to top |
|
|
dobryan Samba Member
Joined: March 24, 2006 Posts: 16501 Location: Brookeville, MD
|
|
Back to top |
|
|
DuncanS Samba Member
Joined: October 17, 2013 Posts: 4583 Location: New Hampshire
|
Posted: Fri Jul 30, 2021 10:17 am Post subject: Re: Rebuild...... 1990 Air Conditioning |
|
|
Congratulations. Now to tackle the issues from the other topic about wiring.
Have been thinking about isolating the resistors and fans and having a separate relay for each one to cut the load in half at any given point.
And now we have had cool weather once you have it all working. An umbrella at a picnic, I guess.
Duncan |
|
Back to top |
|
|
dabaron Samba Member
Joined: June 21, 2018 Posts: 2559 Location: Philly, mang
|
Posted: Fri Jul 30, 2021 12:32 pm Post subject: Re: Rebuild...... 1990 Air Conditioning |
|
|
i'll be ready for a parts order in Sept. this is impressive. good jorb Dave! _________________ 1991 Vanagon GL Camper
i had no idea i wanted to be a mechanic
"burnin oil and cookin coils" -- Destructo
BiWerks Design, LLC |
|
Back to top |
|
|
djkeev Samba Moderator
Joined: September 30, 2007 Posts: 32584 Location: Reading Pennsylvania
|
|
Back to top |
|
|
greebly Samba Member
Joined: August 27, 2009 Posts: 966 Location: Here and now
|
Posted: Fri Jul 30, 2021 5:00 pm Post subject: Re: Rebuild...... 1990 Air Conditioning |
|
|
Time to break out the space blanket Dave. |
|
Back to top |
|
|
AllRad Samba Member
Joined: December 04, 2016 Posts: 64 Location: Pacific Northwest
|
Posted: Mon Aug 02, 2021 10:42 am Post subject: Re: Rebuild...... 1990 Air Conditioning |
|
|
Hello,
I have been following this thread trying to figure out my own AC. I thought I had it fixed last summer after a relay replacement, a recharge and some minor tinkering with the wiring in the D pillar (just polishing of ground wire eyelets). Anyways, by the time September arrived I had cold air! I used it twice! After that, there was no need.
As a native PNW'er, this has been the hottest year of my life! When I attempted to use the AC again this June, it blew ambient temp air. Which did not surprise me. I figured it needed a recharge of R134a. I took to a local shop who informed me that I had a huge hole in the tube going from the compressor to the evaporation unit. Turns out the hose was making contact with the sheet metal as it bent upwards inside the 'D' pillar and friction did it's thing. So, I got a new hose. Had it recharged and... Nah dah! No cold air.
I decided to pony up for a Vacuum pump and some gauges, which just arrived from the Amazon! Yay! (I have no idea what the hell I am doing!!)
First thing I did was unscrew the blue cap from the low pressure hose. No problems, I could see the top of the Schrader valve. The next thing I tried was unscrewing the red plastic cap from the high pressure valve. To my shock, it unscrewed the whole ensemble. I only recognized this, because instead of seeing the top of a Schrader valve, I saw only a void. An empty tube. nothing tried to escape. No gas. No oil. Photo #2 shows the front of the now removed valve assembly after successfully removing the red plastic cap, but this happened after the whole thing came off. It came off with simple finger and thumb twisting of the red plastic cap! This is what I mean:
Question #1: Under proper AC running circumstances I think this should have resulted in a major spray of R134a and pag oil. True?
Question #2: should there be an 'O' ring inside the Schrader valve 'hole'? |
|
Back to top |
|
|
djkeev Samba Moderator
Joined: September 30, 2007 Posts: 32584 Location: Reading Pennsylvania
|
|
Back to top |
|
|
dabaron Samba Member
Joined: June 21, 2018 Posts: 2559 Location: Philly, mang
|
Posted: Mon Aug 02, 2021 11:47 am Post subject: Re: Rebuild...... 1990 Air Conditioning |
|
|
djkeev wrote: |
I am seeing clearly that the heat from the engine is a BIG obstacle to over come!
When I installed my mattress, the intake air temperatures dropped insignificantly.
I wonder what other drivers would find if they tested what their temperatures are back there.
I know that having a hot bed is a normal thing that owners deal with.
|
i know for fact that adding 3 CANS of Plasticoat to the foam of the engine lid reduce the heat going into the rear mattress. it doesn't block all the heat, but it provides enough thermal resistance that the difference is noticeable.
what is it like with your spacer removed? _________________ 1991 Vanagon GL Camper
i had no idea i wanted to be a mechanic
"burnin oil and cookin coils" -- Destructo
BiWerks Design, LLC |
|
Back to top |
|
|
AllRad Samba Member
Joined: December 04, 2016 Posts: 64 Location: Pacific Northwest
|
Posted: Mon Aug 02, 2021 3:26 pm Post subject: Re: Rebuild...... 1990 Air Conditioning |
|
|
djkeev wrote: |
It looks like you unscrewed the r12 - r134a conversion fittings.
They stay on.
Dave |
Yep, yes. I get that. But it shouldn't be finger tight either, right? It was entirely an accident that I unscrewed the thing (thinking I was only just unscrewing the plastic cap cover, shouldn't I have expected some kind of burst from the pressurized system, assuming it was even halfway to normal?
Said differently, this thing appears to be way empty, like E-M-P-T-Y (or I am missing something fundamental, which is entirely possible)? |
|
Back to top |
|
|
djkeev Samba Moderator
Joined: September 30, 2007 Posts: 32584 Location: Reading Pennsylvania
|
|
Back to top |
|
|
djkeev Samba Moderator
Joined: September 30, 2007 Posts: 32584 Location: Reading Pennsylvania
|
|
Back to top |
|
|
djkeev Samba Moderator
Joined: September 30, 2007 Posts: 32584 Location: Reading Pennsylvania
|
|
Back to top |
|
|
metropoj Samba Member
Joined: April 23, 2004 Posts: 1343
|
Posted: Tue Aug 03, 2021 9:09 am Post subject: Re: Rebuild...... 1990 Air Conditioning |
|
|
djkeev wrote: |
I got out the EZ Clip fittings for the Expansion Valve.......
Dave |
Thanks for your detailed travellings getting your system up and running.
I wanted to ask the group for those of us who don't have new TXV's squirrelled away that we can install, if anyone has had any luck WITH a replacement one ?
I recently pulled an unmolested 90 Passenger van R12 system front to back that even still had a little but of pressure in it, but I never heard it run.
I'd hate to get it installed and find I need an expansion valve and be SOL till I find an OEM one. For this reason I have started looking at going Vintage Air / Small Car system instead ... _________________ John.
86 TiiCo powered Westy. |
|
Back to top |
|
|
djkeev Samba Moderator
Joined: September 30, 2007 Posts: 32584 Location: Reading Pennsylvania
|
|
Back to top |
|
|
AllRad Samba Member
Joined: December 04, 2016 Posts: 64 Location: Pacific Northwest
|
Posted: Tue Aug 03, 2021 1:16 pm Post subject: Re: Rebuild...... 1990 Air Conditioning |
|
|
djkeev wrote: |
AllRad wrote: |
djkeev wrote: |
It looks like you unscrewed the r12 - r134a conversion fittings.
They stay on.
Dave |
Yep, yes. I get that. But it shouldn't be finger tight either, right? It was entirely an accident that I unscrewed the thing (thinking I was only just unscrewing the plastic cap cover, shouldn't I have expected some kind of burst from the pressurized system, assuming it was even halfway to normal?
Said differently, this thing appears to be way empty, like E-M-P-T-Y (or I am missing something fundamental, which is entirely possible)? |
Here are instructions for similar adapter fitings..........
http://www.flyingspares.com/uploads/Instructions/R134CONKIT.pdf
Note that not all brand fittings are the same!
https://www.4s.com/media/3754/4s375-indentifying-retrofit-adapters.pdf
Dave |
I stumbled my way through hooking up my gauge set and vacuuming the AC system to -29 (inches? PSI?). Anyways, a major achievement for me!! That's the good news. It holds the vacuum for 60 minutes no problem. However, after re-checking at 90 minutes the gauges are within one minus hash mark of zero, meaning the vacuum is basically gone.
A little odd that it's not a steady incremental decrease in vacuum. It seems to hold it perfectly for 60 minutes, then it's all gone within a 30 minute span. Perhaps it's the nature of the gauges I bought (cheap).
To help learn the knobs and twisty bits, I've vacuumed the system twice. Now that I've done it a couple of times, it is a pretty simple process.
Question #1: How long should I leave the pump on to vacuum the system? I've read that it only takes 5 minutes. I've also read that nothing less than an hour would suffice.
Question #2: What are our opinions on AC Stop Leak? I see there are products from AC PRO, RedTek and Red Angle... thoughts?
---
---
Cheers! |
|
Back to top |
|
|
djkeev Samba Moderator
Joined: September 30, 2007 Posts: 32584 Location: Reading Pennsylvania
|
|
Back to top |
|
|
AllRad Samba Member
Joined: December 04, 2016 Posts: 64 Location: Pacific Northwest
|
Posted: Tue Aug 03, 2021 3:12 pm Post subject: Re: Rebuild...... 1990 Air Conditioning |
|
|
djkeev wrote: |
You've got options.
An easy inexpensive one but controversial because you introduce moisture and possibly contaminants is to pressurize it like you would a tire.
The proper way is a tank of nitrogen but few of us have that sitting around.
Once pressurized go to each and every fitting and spray it with soapy water, look for bubbles.
Dave |
Oh man, that's what my daughter told me to do. She's an engineer. Thankfully, she does not read this site, or I would never live it down! I think I will give it a go. Do you think a bike pump would do the job?
---
Cheers! |
|
Back to top |
|
|
djkeev Samba Moderator
Joined: September 30, 2007 Posts: 32584 Location: Reading Pennsylvania
|
|
Back to top |
|
|
|