Automotive Air Conditioning Information Forum (Archives)

SteveJ on Sun July 31, 2011 4:52 PM

Year: 2000
Make:

My 2000 Venture is leaking from the rear air line where it humps over the fuel filler hose. It's all wet around the line & dripping - I can see it. There's a section of black plastic-shrink wrap protector covering the line & I can see it bubbling out the end of it.

So I'm sure this is it.

It's a smaller diameter line, so I assume it's the high side. I'd previously pulled good vacuum & held it; I'm thinking the plastic protector might've plugged the hole well enough.

Short of replacing the entire line, what are my repair options?

Thanks!

GM Tech on Sun July 31, 2011 5:37 PM

Huuuuuhhhhh...I've repaired a dozen or more of those ....always at the liquid (3/8) line right above gas tank filler tube-- and under the plastic insulation-mostly on 97-99 U-vans - must go into 2000 as well...anyway- the insulation traps moisture- holds it against the aluminunm pipe- causes a pinhole leak-- and possible lamination issues from the bend in the tubing.....any way the quick est, easiest fix is to install a swagelok aluminum coupler-- works everytime- without a doubt- no leaks---cut 2 inches out of pipe to install it-- you can buy them online- or at your local Grainger dealer--or you can use what is advertised here on this forum---an inline liquid line filter--not for the filter part, but for the "union" part-- see- it require you to cut 2 inches out of the line to install the filter---so be creative and cut the two inches out that contain the pinhole...case closed.. Oh and try to install it in a straight section of tubing- sometimes the tubing doesn't like to bend back right if you cut into a curve....if all else fails- then cut out about 2 feet and use 2 swageloks and a piece of scrap 3/8 tubing you have in your aluminum scrap pile-- I've done that twice---cost of lines is $600 plus-- or use a $20 swagelok-- it's your chioice...... oh you must remove all old plastic insulation and positively identify the pinhole- by watching it bubble- to be sure you cut out the right spot....

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The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......

Edited: Sun July 31, 2011 at 5:38 PM by GM Tech

SteveJ on Sun July 31, 2011 5:46 PM

Thanks for the advice! A couple of questions:

If I go the swagelok route, can you spec out exactly what PN you use for me? I know I'm asking a lot, but you've obviously done this before and I can see me getting the wrong stuff....

If I use the in-line filter offered here, which direction is the flow? Front-to-rear? Thanks!

Edited: Sun July 31, 2011 at 5:47 PM by SteveJ

GM Tech on Sun July 31, 2011 6:18 PM

Swageloks are made for the specific type of metal you are adapting to....so you want a swagelok with "A" in the part number for your aluminum 3/8 line.. I found it to be
A-600-6

they are all over the internet auction sites...that's where I got my last bag of 20...for about $80...

The flow is from front to rear on the rear liquid (3/8) line.


Swagelok part number A-600-6


-------------------------
The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......

Edited: Sun July 31, 2011 at 7:19 PM by GM Tech

SteveJ on Sun July 31, 2011 7:35 PM

Update: I cut & removed the black plastic protector & found the leak. It's still hissing as the system bleeds down. Inspecting the rest of the tubing that was covered; I'm not sure I trust the integrity of that section. I'd like to cut-out & replace that section.


So, if I use the Swagelok connectors, can I reasonably expect to have a decent repair if I get bulk tubing & bend it to match that section? Where can I get the tubing & what's the recommended tool to bend it?

Kevin

GM Tech on Sun July 31, 2011 10:11 PM

Any salvage yard should let you cut out a section of tubing- from any other GM vehicle-- use your pipe cutter for a clean cut....

Just pick out a U-van (Silhouette, Montana, Venture) and cut out a straight section from under it---then just bend it by hand to make it fit--the main thing is don't let it rub anything after it is installed.-- You can do most of your bending after it is installed- is much easier this way.

-------------------------
The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......

SteveJ on Mon August 29, 2011 9:37 PM

I finally tackled my leaking line. It took a few weeks to get the correct Swagelok fittings, a 5' bulk section of tubing, and some spring benders. Hacked the leaky section of line out & fumbled around bending & cutting the replacement patch. Finally got everything where I wanted it & installed the Swageloks following the instructions to tighten 1 & 1/4 turns. Pulled a good vacuum & charged it up! So far, so good!

My thanks to GM Tech for pointing me in the right direction on this one!

GM Tech on Mon August 29, 2011 10:14 PM

Nice to win one once in awhile............

-------------------------
The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......