Air conditioner high pressure tube leak

Air conditioning season is not off to a good start this year. The high
pressure line that is routed under the battery developed a pinhole leak.
The tube showed signs of corrosion, probably caused by battery acid.
I attempted a repair by cutting out a few inches of metal tubing and
bridging across the gap with some of the high-pressure rubber hose
that's used for fuel injection. This was a good snug fit secured by
standard hose clamps. The fix worked for a couple of weeks until one end
of the hose blew off.

I reconnected the hose using a touch of Aviation Form-A-Gasket, but I
don't have any confidence in this repair. I expect another blow-out.

There is another '03 Forester in the junk yard at the moment, but its
high pressure line has a similar, though less-severe, corrosion problem.
The tubing is also available new from the dealer, but it looks to be
a major effort to replace while the engine is in the car.

Question: How would a pro fix this problem?

--
THINGS TURN OUT BEST FOR THOSE WHO MAKE THE BEST OF THE WAY THINGS TURN OUT
.. ART LINKLETTER R.I.P

On Friday, May 24, 2019 at 8:10:11 AM UTC-10, Jack Myers wrote:
> Air conditioning season is not off to a good start this year. The high
> pressure line that is routed under the battery developed a pinhole leak.
> The tube showed signs of corrosion, probably caused by battery acid.
> I attempted a repair by cutting out a few inches of metal tubing and
> bridging across the gap with some of the high-pressure rubber hose
> that's used for fuel injection. This was a good snug fit secured by
> standard hose clamps. The fix worked for a couple of weeks until one end
> of the hose blew off.
>
> I reconnected the hose using a touch of Aviation Form-A-Gasket, but I
> don't have any confidence in this repair. I expect another blow-out.
>
> There is another '03 Forester in the junk yard at the moment, but its
> high pressure line has a similar, though less-severe, corrosion problem.
> The tubing is also available new from the dealer, but it looks to be
> a major effort to replace while the engine is in the car.
>
> Question: How would a pro fix this problem?
>
> --
> THINGS TURN OUT BEST FOR THOSE WHO MAKE THE BEST OF THE WAY THINGS TURN OUT
> .. ART LINKLETTER R.I.P

He'd replace the hose. You can get them cheap on eBay - for around 20 bucks.

On 5/24/2019 2:09 PM, Jack Myers wrote:
> Air conditioning season is not off to a good start this year. The high
> pressure line that is routed under the battery developed a pinhole leak.
> The tube showed signs of corrosion, probably caused by battery acid.
> I attempted a repair by cutting out a few inches of metal tubing and
> bridging across the gap with some of the high-pressure rubber hose
> that's used for fuel injection. This was a good snug fit secured by
> standard hose clamps. The fix worked for a couple of weeks until one end
> of the hose blew off.
>
> I reconnected the hose using a touch of Aviation Form-A-Gasket, but I
> don't have any confidence in this repair. I expect another blow-out.
>
> There is another '03 Forester in the junk yard at the moment, but its
> high pressure line has a similar, though less-severe, corrosion problem.
> The tubing is also available new from the dealer, but it looks to be
> a major effort to replace while the engine is in the car.
>
> Question: How would a pro fix this problem?
>
In non-mobile HVAC, a technician would cleanly cut the defective section
out and braze in a replacement. Easy enough with experience but in this
sort of AC the lines are traditionally copper. I guess that there must be
some way of handling the task with steel automotive lines but I don't know
what it is.

Failing high-side lines can be exciting. A long time ago I had a rubber
line from the compressor on my Fiat 128 rupture while driving down the Las
Vegas Strip; a huge white cloud, looking like smoke, belched from under the
hood and the engine locked immediately from ingesting the Freon vapor and I
thought I was really cooked. With a rubber hose it was a pretty simple fix.

Jack Myers wrote:
> Air conditioning season is not off to a good start this year. The high
> pressure line that is routed under the battery developed a pinhole leak.
> The tube showed signs of corrosion, probably caused by battery acid.
> I attempted a repair by cutting out a few inches of metal tubing and
> bridging across the gap with some of the high-pressure rubber hose
> that's used for fuel injection. This was a good snug fit secured by
> standard hose clamps. The fix worked for a couple of weeks until one end
> of the hose blew off.
>
> I reconnected the hose using a touch of Aviation Form-A-Gasket, but I
> don't have any confidence in this repair. I expect another blow-out.
>
> There is another '03 Forester in the junk yard at the moment, but its
> high pressure line has a similar, though less-severe, corrosion problem.
> The tubing is also available new from the dealer, but it looks to be
> a major effort to replace while the engine is in the car.
>
> Question: How would a pro fix this problem?

A pro would replace the a/c line.
However, if it was for my own car and it involved removing the engine
then I would cut out the bad section and install a short piece of the
same material (aluminum?) using flare fittings.

Jack Myers wrote:
> Air conditioning season is not off to a good start this year. The high
> pressure line that is routed under the battery developed a pinhole leak.
> The tube showed signs of corrosion, probably caused by battery acid.
> I attempted a repair by cutting out a few inches of metal tubing and
> bridging across the gap with some of the high-pressure rubber hose
> that's used for fuel injection. This was a good snug fit secured by
> standard hose clamps. The fix worked for a couple of weeks until one end
> of the hose blew off.
>
> I reconnected the hose using a touch of Aviation Form-A-Gasket, but I
> don't have any confidence in this repair. I expect another blow-out.
>
> There is another '03 Forester in the junk yard at the moment, but its
> high pressure line has a similar, though less-severe, corrosion problem.
> The tubing is also available new from the dealer, but it looks to be
> a major effort to replace while the engine is in the car.
>
> Question: How would a pro fix this problem?
>

Either replace the line OR use a line repair kit. Those are really
handy, they use a section of the correct tubing and two compression
unions to replace the damaged line. There are also kits that replace
metal lines with rubber to give you bending ability.

https://surrauto.com/air-conditioning/
https://www.napaonline.com/en/p/NDP82017821

as examples. I have a big kit that Dorman used to sell. Really can get
you out of a jam.

Many parts stores can get the individual pieces as well, Take the piece
you cut out with you and match it up.

--
Steve W.

On 5/24/2019 1:09 PM, Jack Myers wrote:
> Air conditioning season is not off to a good start this year. The high
> pressure line that is routed under the battery developed a pinhole leak.
> The tube showed signs of corrosion, probably caused by battery acid.
> I attempted a repair by cutting out a few inches of metal tubing and
> bridging across the gap with some of the high-pressure rubber hose
> that's used for fuel injection. This was a good snug fit secured by
> standard hose clamps. The fix worked for a couple of weeks until one end
> of the hose blew off.
>
> I reconnected the hose using a touch of Aviation Form-A-Gasket, but I
> don't have any confidence in this repair. I expect another blow-out.
>
> There is another '03 Forester in the junk yard at the moment, but its
> high pressure line has a similar, though less-severe, corrosion problem.
> The tubing is also available new from the dealer, but it looks to be
> a major effort to replace while the engine is in the car.
>
> Question: How would a pro fix this problem?
>
It has been ages since I played with AC issues. But my recollection is
that the high side pressure is in at least several hundreds of pounds
per square inch, and sometimes up to a thousand. That's why the hose is
not cut off and fixed with hose clamps at the ends as the car comes from
the factory, but rather has special fittings that for most of us would
have to come mounted on the hose. So that is why you buy a replacement
hose rather than attempt to splice the old one... And that says the
answer to your question is "the pro would get a replacement hose, with
the fittings, from a reputable supplier."

To be honest I am amazed that it "worked for a couple of weeks"! This is
coming from someone who has been improvising his way around what the
books say to do for decades, that hose is not a good place to play.
Bob Wilson, WA9D

John McGaw > wrote:
> On 5/24/2019 2:09 PM, Jack Myers wrote:
> > Air conditioning season is not off to a good start this year....
> > ... The fix worked for a couple of weeks until one end
> > of the hose blew off.
> >
>

> Failing high-side lines can be exciting. A long time ago I had a rubber
> line from the compressor on my Fiat 128 rupture while driving down the Las
> Vegas Strip; a huge white cloud, looking like smoke, belched from under the
> hood and the engine locked immediately from ingesting the Freon vapor and I
> thought I was really cooked. With a rubber hose it was a pretty simple fix.

No kidding! I was in the drive-through line at In-n-Out when it blew.
My mind immediately flashed back 50 years to a time when I was working
on a factory floor and a compressed air line about 10 yards away let go.

--
Anything not pertaining to pachyderms is irrelphant.

Steve W. > wrote:
> Jack Myers wrote:
> > Air conditioning season is not off to a good start this year.
> >
> > I reconnected the hose using a touch of Aviation Form-A-Gasket, but I
> > don't have any confidence in this repair. I expect another blow-out.
> >

> Either replace the line OR use a line repair kit. Those are really
> handy, they use a section of the correct tubing and two compression
> unions to replace the damaged line. There are also kits that replace
> metal lines with rubber to give you bending ability.

> ...

Thanks for the pointers, Steve. Really appreciate it. The original pin-
hole was located on a bend in the tubing. Stands to reason. High stress
region.

Jack Myers wrote:
> Steve W. > wrote:
>> Jack Myers wrote:
>>> Air conditioning season is not off to a good start this year.
>>>
>>> I reconnected the hose using a touch of Aviation Form-A-Gasket, but I
>>> don't have any confidence in this repair. I expect another blow-out.
>>>
>
>> Either replace the line OR use a line repair kit. Those are really
>> handy, they use a section of the correct tubing and two compression
>> unions to replace the damaged line. There are also kits that replace
>> metal lines with rubber to give you bending ability.
>
>> ...
>
> Thanks for the pointers, Steve. Really appreciate it. The original pin-
> hole was located on a bend in the tubing. Stands to reason. High stress
> region.

Not just high stress but the tubing can have internal damage from the
bending process. Being a bend is involved you could use a section of
high pressure "rubber" line and have fittings attached at a place like
NAPA or other places that do hydraulic hose work. Or hit a you-pull it
yard for a replacement hose and use a section of that to repair yours.


--
Steve W.

Steve W. wrote:
> Jack Myers wrote:
>> Steve W. > wrote:
>>> Jack Myers wrote:
>>>> Air conditioning season is not off to a good start this year.
>>>>
>>>> I reconnected the hose using a touch of Aviation Form-A-Gasket, but I
>>>> don't have any confidence in this repair. I expect another blow-out.
>>>>
>>> Either replace the line OR use a line repair kit. Those are really
>>> handy, they use a section of the correct tubing and two compression
>>> unions to replace the damaged line. There are also kits that replace
>>> metal lines with rubber to give you bending ability.
>>> ...
>> Thanks for the pointers, Steve. Really appreciate it. The original pin-
>> hole was located on a bend in the tubing. Stands to reason. High stress
>> region.
>
> Not just high stress but the tubing can have internal damage from the
> bending process. Being a bend is involved you could use a section of
> high pressure "rubber" line and have fittings attached at a place like
> NAPA or other places that do hydraulic hose work. Or hit a you-pull it
> yard for a replacement hose and use a section of that to repair yours.
>
>

Federated just put this up about AC repair kits and pieces you can get
at their stores. https://www.youtube.com/watch?v=RxPugO_h0uE


--
Steve W.