Hello,
Today I went to the mechanic to get my A/C recharged and he told me I needed the "thermal expansion valve" and my shrader valves replaced.  He quoted me 700 for the job!  I went to the local parts store and they said a thermal expansion valve is about a 50 dollar part.  How hard would it be to fix it myself?  Is it possible?  And how does the mechanic know that the valve is broken anyways?  Please help!  It's hot out here!
Thanks!

Hello,
Today I went to the mechanic to get my A/C recharged and he told me I needed the "thermal expansion valve" and my shrader valves replaced.  He quoted me 700 for the job!  I went to the local parts store and they said a thermal expansion valve is about a 50 dollar part.  How hard would it be to fix it myself?  Is it possible?  And how does the mechanic know that the valve is broken anyways?  Please help!  It's hot out here!
Thanks!

If it is older than '93, then you are probably dealing with an A/C system that uses a type of refrigerant that is no longer easily available.  Much of the $700.00 cost is making the conversion.  The Schrader Valves are used to add and bleed the refrigerant from the system.  In a R134a system (1993 and newer vehicles), the Schrader valves are a different size than in the ones on an older system so you can't accidentally (or easily) put the old refrigerant in a newer system.

The conversion will require a great deal of component replacement (o-rings, etc.) as the new refrigerants (R134A) have different properties and do not neccessarily work well with the old seals that have been exposed to the old refrigerant.

So, Bottom line -- Built Before R134A systems (1993) , spend money ($700?) on a conversion or get a bikini top and roll down the windows...

Sorry

Can't you just add the oil or protective stuff to run R-134 in a R-12 system?  At least that is how they offer it at the stores to convert from one to the other.   

Can't you just add the oil or protective stuff to run R-134 in a R-12 system?  At least that is how they offer it at the stores to convert from one to the other.   

I suppose so... But in every endeavor, there is the right way and then there is the quick way.

BTW, I am a shadetree mechanic.  My other post is just an opinion.  If we were talking about a Samurai (the original poster has not revealed what vehicle he is talking about), then the quick way might be better -- assuming it will work at all.  No point in spending $700 on a truck that's worth the same amount...

I work on AC systems all the time for BC transit (Buses) they use multiple automotive systems
the oil that is used in r134 is called PAG oil and it is not compatible with r12 systems.  The reasons it costs 700.00 was pointed out by ACK but the main reason you have to switch over from r12 to r134 is that the government does not allow the sale of r12 so you have to switch to r134 and it also costs them money to dispose of the r12.

Thats why it costs 700 and for AC that is not to bad a price!

Dustin

I work on AC systems all the time for BC transit (Buses) they use multiple automotive systems
the oil that is used in r134 is called PAG oil and it is not compatible with r12 systems.  The reasons it costs 700.00 was pointed out by ACK but the main reason you have to switch over from r12 to r134 is that the government does not allow the sale of r12 so you have to switch to r134 and it also costs them money to dispose of the r12.

Thats why it costs 700 and for AC that is not to bad a price!

Dustin

...and there is the answer!  Thanks Dustin!

I found this website that talks about converting it over.  It looks like the guy did most of the work himself and then took it to a shop to be evacuated and filled.

http://bernardembden.com/xjs/134/index.htm

I will probably do this myself. 

I can see where a shop would charge $700 after seeing the labor involved in the proper way of converting from r12 to r134.

Good luck,

Sorry guys I forgot to add the year of my truck.  I have a 1996  Tracker...  My bad

Sorry guys I forgot to add the year of my truck.  I have a 1996  Tracker...  My bad

Then all of the above does not apply.  You already have an R134A system (as do I on my '96 Tracker...).  Maybe the expansion valve needs replacing (it is reccommended if the system has been opened and discharged for a long time)  -- then again or maybe not.

I recently rebuilt my engine in the '93 (with R134A) and ended up replacing only the drier unit just to be safe.  Get the drier's OEM part number from a Suzuki or Chevy dealer parts department then go to an auto parts store and save BIG!  After recharging the system with lubricant (pour some directly into the compressor inlet and let is sit for a while) and then charge it with, I think, around 21 oz of R134A.  Or take it somewhere and have the work done.

The shop owner has a bass boat payment coming up and YOU are the person who will be making that payment if you do business with him.

BASS BOAT PAYMENT

HAHAHAHAH!

Dustin

If I can get that valve is there anything I need to know to install it? Or is it just a matter of bolting it in?  Actually I am not sure I know where it goes anyways?  I think it is in the part on the front right of the motor with the A/C hoses coming out of it.  Is that right?  Do I just take it off and open it?  I am pretty sure there is no freon in my system right now.
Any info on how to do this would be awesome!
Thanks!
James
You should see what the guy wanted for the valve gasket replacement!

If I can get that valve is there anything I need to know to install it? Or is it just a matter of bolting it in?  Actually I am not sure I know where it goes anyways?  I think it is in the part on the front right of the motor with the A/C hoses coming out of it.  Is that right?  Do I just take it off and open it?  I am pretty sure there is no freon in my system right now.
Any info on how to do this would be awesome!
Thanks!
James
You should see what the guy wanted for the valve gasket replacement!

If you are talking about the aluminum cylinder  that bolts to the passenger side of the engine compartment next to the radiator, THAT is the drier unit.  The Schrader Valves are on the lines connected to it - one on the input side and one on the output side.  The dealer quoted me 67 bucks for a drier for my '93.  I went to O'Reillys Autoparts with the part number that the dealer parts guy was kind enough to give me and paid 33 bucks for the same unit.


The expansion valve (if it can be called that -- The Suzuki expansion valve system uses a different type of assembly from what is found in more familiar Big Three vehicles) is located inside the passenger compartment next to the A/C condenser  under the dash.  It has a bulblike temperature probe that attaches to the surface of the condenser to control coolant flow.  I got lucky and managed to get my system working properly without replacing that hard-to-get-to component.


BTW, you will need to get (or rent/borrow) a vacuum pump and a set of gages in order to evacuate the system and recharge it.  I have a friend at work who has this stuff and he helped me recharge the system.  Recharging can be done by professionals for around $100 -- a bit more if you replace the drier -- if you feel that you might not be able to do it yourself.

I hope that this thread has been of use to you - and to others who might read it!

So if I can get the expansion valve you are saying I could slap that in myself right?  From the pics I have seen it appears to have two threaded valves and a hose connected to it.  I imagine I can take the old one out and install a new one unless fluids are going to start spraying out all over?
When I went to the shop they had filled my ac to check for leaks and then drained it out when they were done.  Does this mean I would still need to evacuate the system?  Or was that done when they tested and drained it?  I know the local auto store sells freon that comes in a can with a gauge and hoses and such.  Would that be all I need to recharge it then after installing the expansion valve? 

also where exactly is this valve located?  I thought the guy told me it is inside of some other part?  Could that be the evaporator box under the dash?  If so how does that come out?

also where exactly is this valve located?  I thought the guy told me it is inside of some other part?  Could that be the evaporator box under the dash?  If so how does that come out?

The valve is located in the evaporator/condenser box in the dash.  I have a pic of it in my Tracker FSM A/C supplement (I bought it in an eBay Auction).  You might be able to find a description of it and how to remove it in a Chilton's Samurai/Sidekick/Geo tracker repair manual.  It may also be in the Haynes manual, but I doubt it.

Personally, I would not worry about the valve.  If your system has been opened up (ie a fitting removed causing the system to drain into the atmosphere and possibly fill with air) then I might worry less about the valve and more the drier - especially if you live in a high-humidity part of the country.  If you have a slow leak, I'd get the leak fixed and the system recharged.

The repair guy probably did not "fill the system with refrigerent" to check it.  He most likely hooked up his vacuum pump to the system and "pulled a vacuum" to see how high a vacuum the system would take and weather it "leaked down" after a few minutes indicating a slow leak in the system.

EDIT:

Here is a picture of the shrader valves and the drier in my '93 Sidekick.  I should have taken a pic of the same components on the '96 Tracker but the 'Kick was easier to get to and they are basically the same layout:



END EDIT:


If I were you, I'd either spend a lot of time reading the Chilton, Haynes or (if you can find one) a '96 Factory Service Manual (FSM) to determine if you really want to fix the A/C yourself. Or, you might be better off taking it to a reputable mechanic armed with what you have learned in this thread and what you have read in the manuals or discussed with knowing friends to keep from getting ripped off like your $700 mechanic tried to do.

I hope this helps!