Has anyone converted dual AC (front and rear) to front only?
1999montana
06-20-2008, 05:09 PM
Our van has developed a leak in the lines leading to the rear air; the leak is on the suction side of the system in a piece of pipe against the firewall, immediately below the TC and ABS units.
Apparently dealers can repair the pipe (depending on where the leak is; - on a straight run versus a bend in the pipe). To do this, they have access to a tool that allows them to cut out the bad pipe, crimp connectors on and use flexible lines to replace the bad pipe removed.
My alternate thought is to isolate the rear air from the front and just run it with front air only.
The Air Con guy tells me that the easiest way to fix it is to buy the necessary lines for a front air only setup and run from the compressor, to the condenser and back to the evaporator isolating, or disconnecting the rear air.
Has anyone had the dealer attempt the repair using the methods mentioned?
Apparently dealers can repair the pipe (depending on where the leak is; - on a straight run versus a bend in the pipe). To do this, they have access to a tool that allows them to cut out the bad pipe, crimp connectors on and use flexible lines to replace the bad pipe removed.
My alternate thought is to isolate the rear air from the front and just run it with front air only.
The Air Con guy tells me that the easiest way to fix it is to buy the necessary lines for a front air only setup and run from the compressor, to the condenser and back to the evaporator isolating, or disconnecting the rear air.
Has anyone had the dealer attempt the repair using the methods mentioned?
rockwood84
06-21-2008, 01:05 AM
find the hole in the line and go get a piece of high pressure rubber hose and cut the hole out and slip the hose over the metal line and put two hose clamps on each end of the rubber hose,let the rubber hose go at least two inches on the metal pipe. this is about what the dealer is going to do,this should fix it.dealer wanted $210.00 for a six inch piece of heater hose with a quick connect end on it . i fixed it for the price of a foot of heater hose $1.00 and a $0.80 #10 hose clamp.
1999montana
06-21-2008, 12:16 PM
find the hole in the line and go get a piece of high pressure rubber hose and cut the hole out and slip the hose over the metal line and put two hose clamps on each end of the rubber hose,let the rubber hose go at least two inches on the metal pipe. this is about what the dealer is going to do,this should fix it.dealer wanted $210.00 for a six inch piece of heater hose with a quick connect end on it . i fixed it for the price of a foot of heater hose $1.00 and a $0.80 #10 hose clamp.
Thanks for the reply.
I'd considered a home grown solution, BUT one of the lines is high pressure to / from the rear evaporator. Line pressures are usually about 150+ lbs, I believe.
The low side line is only about 30 - 40+ lbs tops.
While pondering the problem and possible solutions to get the entire system working again, I found this site.
http://www.fmsiinc.com/ac/aluminum-tube-repair.htm
They manufacture all the right tools and kits to do permanent repairs.
Looking at the solutions on this site, you could use high quality plumbing grade seamless copper pipe, compression unions or couplings (if they have 'O' ring capability for sealing).
The only concern I might have with the plumbing solution is the electrolysis that might take place between the copper, brass and aluminum pipes in the presence of moisture or road salt.
If my GM dealer uses this or a similar method, AND depending on the cost to re and re the two sections at the firewall location, I may let him do the job. Requires a hoist anyway to get at everything easily and do a complete diagnosis to make sure I haven't missed another spot.
I've already done the worst part of the job, replacing a leaky condenser and verified that the compressor is good, and all of the hoses and connections in the engine bay are clean, dry and leak free.
Seems that the pipes under the van corrode where they are attached to the body. Mine don't look anything like the pictures on this web site I referenced.
If there is more than one place rotting, I'll have them fix that too AND the root cause...the mounting system.
I know the Service Manager personally, so will call him on Monday to see what the options are.
Oh BTW, if you are in edit mode trying to update a thread, DON'T hit the back button after commit :headshake
...it creates a new record...OOPS, discovered that by accident yesterday!
Thanks for the reply.
I'd considered a home grown solution, BUT one of the lines is high pressure to / from the rear evaporator. Line pressures are usually about 150+ lbs, I believe.
The low side line is only about 30 - 40+ lbs tops.
While pondering the problem and possible solutions to get the entire system working again, I found this site.
http://www.fmsiinc.com/ac/aluminum-tube-repair.htm
They manufacture all the right tools and kits to do permanent repairs.
Looking at the solutions on this site, you could use high quality plumbing grade seamless copper pipe, compression unions or couplings (if they have 'O' ring capability for sealing).
The only concern I might have with the plumbing solution is the electrolysis that might take place between the copper, brass and aluminum pipes in the presence of moisture or road salt.
If my GM dealer uses this or a similar method, AND depending on the cost to re and re the two sections at the firewall location, I may let him do the job. Requires a hoist anyway to get at everything easily and do a complete diagnosis to make sure I haven't missed another spot.
I've already done the worst part of the job, replacing a leaky condenser and verified that the compressor is good, and all of the hoses and connections in the engine bay are clean, dry and leak free.
Seems that the pipes under the van corrode where they are attached to the body. Mine don't look anything like the pictures on this web site I referenced.
If there is more than one place rotting, I'll have them fix that too AND the root cause...the mounting system.
I know the Service Manager personally, so will call him on Monday to see what the options are.
Oh BTW, if you are in edit mode trying to update a thread, DON'T hit the back button after commit :headshake
...it creates a new record...OOPS, discovered that by accident yesterday!
1999montana
07-08-2008, 04:22 PM
Time for an update.
The AC saga continues.
The lines to the rear evaporator are perforated in a number of locations and the recommended repair to restore the system is to replace both factory lines with GM replacements (manufactured in two halves). Each half is about $102 (times 4) for a total of $400+ just for the parts. Labor to install is another $200+ with an AC evac and re-charge of about $150.
The estimated cost with re-charge is about $800+ rolled up including taxes (these prices are with a GM employee parts discount and a reduced labor rate of 15%).
Due to the design of the replacement parts a GM dealer must install them as the repair requires unions / joiners manufactured / distributed by FMS Inc. mentioned elsewhere in this thread. The repair also requires a specialty tool that costs about $300 from the same company.
Bottom line, not a do-it-yourself type job.
Second alternative is to replace two lines; - one on the compressor and one on the accumulator to isolate the rear AC and turn the AC into a front AC only.
Cost for the two lines about $180.
Best part, this is a do-it-yourself job requiring an evacuation and recharge at the end. I'm willing to spend $90 to have my AC guy do the evac and re-charge.
Worst case, (but not recommended) I could re-charge with the REDTEK R-12a system, but would have no way to evacuate prior to recharging.
The AC saga continues.
The lines to the rear evaporator are perforated in a number of locations and the recommended repair to restore the system is to replace both factory lines with GM replacements (manufactured in two halves). Each half is about $102 (times 4) for a total of $400+ just for the parts. Labor to install is another $200+ with an AC evac and re-charge of about $150.
The estimated cost with re-charge is about $800+ rolled up including taxes (these prices are with a GM employee parts discount and a reduced labor rate of 15%).
Due to the design of the replacement parts a GM dealer must install them as the repair requires unions / joiners manufactured / distributed by FMS Inc. mentioned elsewhere in this thread. The repair also requires a specialty tool that costs about $300 from the same company.
Bottom line, not a do-it-yourself type job.
Second alternative is to replace two lines; - one on the compressor and one on the accumulator to isolate the rear AC and turn the AC into a front AC only.
Cost for the two lines about $180.
Best part, this is a do-it-yourself job requiring an evacuation and recharge at the end. I'm willing to spend $90 to have my AC guy do the evac and re-charge.
Worst case, (but not recommended) I could re-charge with the REDTEK R-12a system, but would have no way to evacuate prior to recharging.
1999montana
07-15-2008, 04:55 PM
OK, time for another update.
The lines to convert the air to front only came in today.
Part# 10419476 - From Compressor to Condenser and Accumulator
Part #10250488 - from Condenser to Evaporator in the dash*.
(May be a little cheaper on Rock Auto, but with duty and shipping comes out the same).
Cost: $117.75 for the first, $76.50 for the second
BONUS: all seals ('O' rings) supplied - * also comes with a new orifice tube filter installed.
Tough part is removing the old tube from the evaporator at the firewall... uses a connector not seen be mortal man this century and must be handled with care not to bend the new tube or damage the evaporator on installation.
Other than that, it is a straight bolt on.
Then I have to figure out what to do with all the pipes that aren't connected to anything any more.
The lines to convert the air to front only came in today.
Part# 10419476 - From Compressor to Condenser and Accumulator
Part #10250488 - from Condenser to Evaporator in the dash*.
(May be a little cheaper on Rock Auto, but with duty and shipping comes out the same).
Cost: $117.75 for the first, $76.50 for the second
BONUS: all seals ('O' rings) supplied - * also comes with a new orifice tube filter installed.
Tough part is removing the old tube from the evaporator at the firewall... uses a connector not seen be mortal man this century and must be handled with care not to bend the new tube or damage the evaporator on installation.
Other than that, it is a straight bolt on.
Then I have to figure out what to do with all the pipes that aren't connected to anything any more.
1999montana
07-17-2008, 07:52 PM
SUCCESS!
Installed the new lines this afternoon in 38 C (humidex) and charged the system. Was going to have it done professional but thought, what the heck it had been evacuated 2 times already and I did not have the entire system open for any great length of time anyway.
Couldn't remove the connector at the firewall to install the complete new high side line to the evaporator, so I used the first half of the old line still attached, removed the old orifice tube and installed the new orifice tube that came with the lines.
Reattached the new line half that goes to the accumulator. The compressor lines were a snap to install.
If I hadn't stopped to fight with the connector on the firewall, I would have been finished a 1/2 hour sooner.
Put 8 ounces of R-12A in including one can with two ounces of compressor oil and one can of R-12A refrigerant. At this point I am 4 ounces low, but the sucker is blowing cold air again. Am going to add a can of Pro Seal (2 ounces) which will top it up to 10 ounces, 2 ounces less than it should have, but hope this won't affect its efficiency ...if so, I'll add a second can of compressor oil to bring it to a full 12 ounces.
Works OK, but I think I will add the last two ounces just for GP's after running it for a day or so now.
Installed the new lines this afternoon in 38 C (humidex) and charged the system. Was going to have it done professional but thought, what the heck it had been evacuated 2 times already and I did not have the entire system open for any great length of time anyway.
Couldn't remove the connector at the firewall to install the complete new high side line to the evaporator, so I used the first half of the old line still attached, removed the old orifice tube and installed the new orifice tube that came with the lines.
Reattached the new line half that goes to the accumulator. The compressor lines were a snap to install.
If I hadn't stopped to fight with the connector on the firewall, I would have been finished a 1/2 hour sooner.
Put 8 ounces of R-12A in including one can with two ounces of compressor oil and one can of R-12A refrigerant. At this point I am 4 ounces low, but the sucker is blowing cold air again. Am going to add a can of Pro Seal (2 ounces) which will top it up to 10 ounces, 2 ounces less than it should have, but hope this won't affect its efficiency ...if so, I'll add a second can of compressor oil to bring it to a full 12 ounces.
Works OK, but I think I will add the last two ounces just for GP's after running it for a day or so now.
1999montana
07-20-2008, 08:38 PM
And yes, while there is a Santa Claus, Virginia....there are no fans when the AC is not working.
At moderate temperatures, the high / low pressure switch on the AC disables them.
...I don't know if they would kick in if the coolant reached 240 F or so...go figure!...
At moderate temperatures, the high / low pressure switch on the AC disables them.
...I don't know if they would kick in if the coolant reached 240 F or so...go figure!...
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