SaabCentral Forums banner
1 - 9 of 9 Posts

·
Registered
Joined
·
23 Posts
Discussion Starter · #1 ·
Hi friends,

My project car Saab has developed an AC leak in the peak of Arizona's summer. Started with blowing warm air on the passenger side only. After adding some R134a it blew cold for a few days but it seems to be a major leak, as now all four vents are blowing warm.

I was planning on following Chris Fix's advice from this video (
) and put some refrigerant with UV dye in, find the culprit part (my money is on the condenser and am really hoping it's not the evaporator), have a mechanic drain the refrigerant, replace part, recharge system.

I have never worked on AC before though so wanted to get the forum's take:

1) As the leak seems to be draining the refrigerant pretty quickly, do I necessarily need to go to a mechanic to drain out the refrigerant before replacing the part?
2) Has anyone had luck recharging the system themselves with a few cans of R134? Or is the needed weight of refrigerant so delicate that you need to take it to a shop?
3) Is this a job best left to a mechanic from a "don't inhale chemicals to save money" perspective?
 

·
Registered
Joined
·
525 Posts
If you don't have the tools to do the job properly (a manifold gauge set and vacuum pump) then it is best to have a shop do the diagnosis and repair. You are supposed to recover R134a, not just vent it but your system is leaking then there's not much to recover, no?

Filling the system is supposed to be done by weight since the 9-3 has a variable-displacement compressor and a thermal expansion valve. You can get close enough with a gauge set and thermometer though.
 

·
Registered
Joined
·
324 Posts
You can do it yourself if careful, however after having a mechanic drain the remaining r134a & replacing necessary parts you need to pull a vacuum prior to refilling with new r134a (you also need to replace PAG oil depending on the parts removed & whether they contain the correct amount of oil). All of this requires manifold gauges & a general understanding of how much the system requires (by weight) vs how much is in each can added.

FWIW no matter what part is replaced at minimum the drier needs to be replaced (some would argue the condenser as well).
 

·
Registered
Joined
·
16 Posts
I have a grey market 2008 9-3 Aero Nordic Convertible I brought into the US. I had a slow leak. It would seem the evaporator core is the common culprit. They can be done at home. I wouldn't be overly concerned about releasing a bit of R134.
If you want a run down I'll be glad to provide information.
I would suggest the Evaporator, Expansion valve, Receiver Dryer and all new seals.
I hope that isn't the case with your vehicle. Below is the Youtube link to give you an idea of what you're getting into.
 

·
Registered
Joined
·
226 Posts
Mine has a small leak from the ac line schrader valves- i will replace it one of these days.
I’ve been topping off every year or two using the can of r-134 following the instructions on the can.
If u open the system u will need to draw a vacuum as the other posts have mentioned.
 

·
Registered
Joined
·
14 Posts
1. You don't need a mechanic to recover the refrigerant, as you can buy (expensivo) or rent a recovery unit to then recycle the old refrigerant. You then need a vacuum pump to test leaks, remove remaining refrigerant and moisture, guages (understanding of how to read), pag oil, new schraders, and a new drier. It is a US federal crime to purposefully leak refrigerant punishable with both jail time and fines in the tens of thousands FYI. There is an up to $10,000 reward for those who inform authorities so be careful please.

2. Adding too much can be as productive as having too little refrigerant and needs to be put in at once based on weight not just pressure readings. You can get lucky adding a can or two but if you're adding, then you have a leak that needs to be fixed which also means you may be accumulating moisture in the drier which has a finite capacity.

3. Unless you are serious about learning AC work (which can be very valuable both as a homeowner and auto perspective) and invest some up front cash on quality tools and do it enough to justify those tools, I would recommend that you take it to a reputable AC specialist.
 

·
Registered
Joined
·
14 Posts
Mine has a small leak from the ac line schrader valves- i will replace it one of these days.
I’ve been topping off every year or two using the can of r-134 following the instructions on the can.
If u open the system u will need to draw a vacuum as the other posts have mentioned.
If you want to replace just the schrader valve without "breaking" the system, I use a schrader tool that allows replacement without the gas from escaping. Such as this schrader tool. Practice it on a bicycle tire first but this sounds like it may save you some time and coin.
282363
 

·
Registered
Joined
·
226 Posts
1. You don't need a mechanic to recover the refrigerant, as you can buy (expensivo) or rent a recovery unit to then recycle the old refrigerant. You then need a vacuum pump to test leaks, remove remaining refrigerant and moisture, guages (understanding of how to read), pag oil, new schraders, and a new drier. It is a US federal crime to purposefully leak refrigerant punishable with both jail time and fines in the tens of thousands FYI. There is an up to $10,000 reward for those who inform authorities so be careful please.

2. Adding too much can be as productive as having too little refrigerant and needs to be put in at once based on weight not just pressure readings. You can get lucky adding a can or two but if you're adding, then you have a leak that needs to be fixed which also means you may be accumulating moisture in the drier which has a finite capacity.

3. Unless you are serious about learning AC work (which can be very valuable both as a homeowner and auto perspective) and invest some up front cash on quality tools and do it enough to justify those tools, I would recommend that you take it to a reputable AC specialist.
This is good advice.
I suppose another option could be to pay the mechanic recover the refrigerant and then do the mechanical repairs yourself (change evaporator, etc),
When everything is installed then go back to the mechanic and let him recharge / refill the AC with his equipment.
 

·
Registered
Joined
·
226 Posts
If you want to replace just the schrader valve without "breaking" the system, I use a schrader tool that allows replacement without the gas from escaping. Such as this schrader tool. Practice it on a bicycle tire first but this sounds like it may save you some time and coin. View attachment 282363
I appreciate it! Good price too.
Practicing on a bicycle tire is a good tip. I will do it when the time comes.
 
1 - 9 of 9 Posts
Top