964 a/c high pressure line from compressor removal..

[bigchillcar]

found the source of my a/c charging woe - and it's not the evaporator thank goodness! but there's a perforation in the aluminum line that comes out the hose portion of the high pressure line immediately downstream of the compressor. the perforation looks like the tip of a flat head screwdriver roughly..about a cm long and maybe 1-2 mm wide. my wrench would like to tig weld, but it's difficult to get into his shop..busy time of the year and it's getting hot outside. i have a friend who's an excellent tig welder who could do the job, but the line will require removal. can anyone tell me how to proceed? i know where one end starts (compressor), but where does the other end detach? any special tools required? thanks!

[AFJuvat]

They should end at the drivers side of the engine compartment, near the firewall.

Just wrenches, and some care, you do not want to damage the hose further

[Tom W]

IIRC there is a connection close to the engine compartment and then a separate line that goes up and terminates just above the left front wheel. I thought it was the hoses from the compressor across the top of the engine that go into a piece in the left rear wheel well. Then a separate line from the rear wheel routed down along the rocker panel and up to above the front wheel (you will need to remove the fender liners, the wheels and I had to pull the washer fluid reservoir too). It's been a year or so, but that's what I recall.

No special tools are needed. Just have a shop remove the fluid before you remove the lines to preserve the environment.

[bigchillcar]

thanks, fellas...i'll be verrrry careful. that's an expensive line. i'll check tomorrow to see if it enters the wheelwell (better i think) or the firewall, as you say afjuvat. i had some experience yesterday with removing those fender liners. i'll have to remove the front passenger side soon to replace the hokey 'air horns' i found connected where i should have decent horns. anyway, sounds like jacking the car, removing the wheel and having a good approach to the connection is just the ticket. just regular metric wrenches then to disconnect both sides? boy, i look forward to getting this to my tig friend!

[bigchillcar]

haven't done the job yet, but plan on it in the next few days, as the tig welder won't be available until next week anyway.

i see that the aluminum high pressure line does enter the fender from inside the engine compartment. and as there's a fender liner at the top of the wheelwell arch, i'm betting that the next connection is right inside it. i plan to disconnect forst at the compressor, remove wheel, remove liner, disconnect line at junction and hopefully pull it through the wall, pulling from the engine compartment side. there's also a screw that holds both lines against the forward firewall that will have to come out. should be it. sound about right?

[bigchillcar]

hey..and i took pics. no props?

still waiting on my receiver/drier from pelican. anyone know in which fender well it's located? it's not in the driver's rear for sure. front passenger wheel well behind the wheel? the oil cooler is there behind the liner in front of the wheel.

btw, didja know that the 964 doesn't have an oil cooler on the engine? i didn't. just the fron oil cooler. glad i found the leak last week and got the cooler cleaned out from all the gummed up oil..couldn't even see through it anywhere! lots of brake cleaner and high pressure air took care of that..new hose clamps for the oil lines..

[bigchillcar]

for all of you diligently foloowing this fascinating thread...

my friend tig welded the high pressure line and the new receiver drier came in from pelican today. progress..

[LeRoux Strydom]

Hey Ryan, am I glad to hear your evaporator was fine and that you found the leak in an easier place to fix. Did you put a dye in the oil to test for the leaks, or did you spot the perforation yourself? I assume it was not possible to weld the line in-situ? Good luck with finally getting some cold air.

[bigchillcar]

hi leroux. not there yet, but almost! couldn't repair in situ, as the hole was on the back side of the line, way in the back. haven't put the line back in yet..will in a few days..have a new r/d to install as well. will let you know..cravin' some cold!

[bigchillcar]

hurrah hurrah...re-installed the high pressure line and new r/d, evacuated for about 30 minutes, added tracer dye for future troubleshooting and charged with three cans of freeze-12. i have working air now.

[AFJuvat]

congratulations!

Wasn't so hard was it?

[bigchillcar]

mike..you have no idea how relieved i was to find there were no more leaks once it was hooked up to the vacuum pump. whew. i kept thinking we'd find the evaporator was toast anyhow..

[Don Plumley]

Great job!

[bigchillcar]

thanks, don...working a/c is just really..cool.

[bazar01]

Hi Ryan, are there supposed to be rubber grommets in those holes for the low and high pressure hoses?
I just checked mine and there seemed to be one for each hole.
Were yours still there or they just dry-rotted and caused the aluminum tubing to rub on the sheet metal.
I need to check those hoses too. Thanks.

[bigchillcar]

bazar, yes there's a rubber grommet that protects the two lines as they pass into the wheel well. mine was in good condition, no dry rot. my line had a cut on the backside, way in the way towards the firewall, probably about a 6 -8" from that end that had the look you'd expect from a hacksaw blade (although i seriously doubt this was the cause..i think it happened somehow during an engine removal, return most likely).

[bazar01]

Great!

I just vacuumed my system and it held 29.5" Hg.
Then pressurized with a little R134A and Nitrogen to 300 psi, then sealed it up and disconnected the a/c clutch.
I will be driving around with no a/c for about a month while testing with electronic sniffer and pressure gauge for loss of pressure.
Cross my fingers.
Thanks.

[bigchillcar]

going in today to get mine checked over..just doesn't seem as cold as i think it should be. tracer dye in it..guess i hope it finds no leaks! right?? hope maybe it just needs more freon..using 'freeze-12'..may not be quite as cold as r-12?

good luck, bazar.

[bazar01]

How was your low and high side pressure readings?
Pressure-temp chart for R12:

32F - 30 psig
156F - 250 psig

Make sure the low side pressure does not drop below 30 psig or the evaporator will ice up and block air flow.
The high side should not reach >250 psi in idle. Check your condenser fan operation and overcharging of refrigerant if it does.
If overcharged, recover the refrigerant.

So far, my pressures are holding up. No leaks according to my Inficon electronic leak detector. Cross fingers.

[bigchillcar]

bazar, going to check next week. we put tracer dye and will check for leaks as well, but i used freeze-12..do you think the pressure values change much from r-12? also, i believe after a half evacuation we added three cans of the stuff..they didn't add any additional oil to the system though and i wondered about that.