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A/C compressor question..

  • Thread starter Thread starter 808Gt
  • Start date Start date May 4, 2009

808Gt

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#1
  • May 4, 2009
  • #1
I wanted to know if I can drive my car around while the a/c compressor on the have the lines disconnected.... meaning the compressor is bolted on and the belt is on but the lines and the electric plug is of?

Im taking the a/c parts out to replace them and also fix a hole behind the evap/heater core box, but I will not have all the parts ready, i will be getting it one by one...
 

jrichker

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Cap the lines and the compressor will be OK.

Tools you will need to recharge the system:
See - Harbor Freight Tools - Quality Tools at the Lowest Prices for the A/C charging gauges you will need.

You will need a vacuum pump to remove the air and moisture from the system once it is all assembled.
My current vacuum pump is a refrigerator hermetic unit (motor & compressor in one unit). It was a free-bee from a local used appliance store. I bolted it down to a piece of plywood & soldered a 1/4" flare fitting on the suction line. It works great, pulls 29" of vacuum in about 10 minutes or less. I have used it several times and have had excellent results.



See R134a Conversion for R134a Conversion & recharge help.

You will need to replace the accumulator/dryer (aluminum canister) mounted on the firewall near the evaporator lines. The accumulator/dryer will soak up moisture from the air and will no longer be any good. Do not connect the new accumulator/dryer to the system until after you have flushed it out. Do not let the accumulator/dryer be uncapped and exposed more than 30 minutes. It is best to wait to connect it just before you pull a vacuum. Fail to flush the system and replace the dryer and it will fail quickly. Moisture, refrigerant and heat will make acid that eats up the A/C system from the inside.
 

808Gt

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thanks jrichker very good info.

I had bought a new compressor after I had my a/c system checked and re-charged with r134a myself and worked for awhile but I needed to replace the evap. and condenser.. are the ones from checkers, napa etc. good products?

also would I have to change the lhigh line or will I be ok with just changing the accumulator/dryer and line?
 

jrichker

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808Gt said:
thanks jrichker very good info.

I had bought a new compressor after I had my a/c system checked and re-charged with r134a myself and worked for awhile but I needed to replace the evap. and condenser.. are the ones from checkers, napa etc. good products?

also would I have to change the lhigh line or will I be ok with just changing the accumulator/dryer and line?
Click to expand...

Changing the accumulator/dryer and line should be sufficient. Just be sure to vacuum the system down for 30-50 minutes when you install the accumulator/dryer and line. Having a warm engine compartment helps the vacuum process draw all the moisture out of the system, so drive around for a few minutes prior to installing the accumulator/dryer and pulling a vacuum.
 

808Gt

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ahh ok, yeah im jus gonna change all the lines ...

so basiclly I can take everything off the car besides the compressor and just plug the two ports on the compressor...

also when i install everything could I get an a/c shop to just refill the system?
 

jrichker

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808Gt said:
ahh ok, yeah im jus gonna change all the lines ...

so basiclly I can take everything off the car besides the compressor and just plug the two ports on the compressor...

also when i install everything could I get an a/c shop to just refill the system?
Click to expand...

They will vacuum it down and recharge it. All the fox based A/C systems used R12 refrigerant, which is very expensive and has limited availability. You must have an EPA 609 license to purchase R12. A single 12 oz can sells for $40-$60, and it takes 28-32 oz to fill the system. You may consider one of the R12 replacements or an R134a conversion. The R134a conversion will add another $75-$250 to the service bill. If it needs more refrigerant later, you can get R134a for $7-$9 a can at the auto parts store.
 

backfocus

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I had bought a new compressor after I had my a/c system checked and re-charged with r134a myself and worked for awhile but I needed to replace the evap. and condenser.. are the ones from checkers, napa etc. good products?

also would I have to change the lhigh line or will I be ok with just changing the accumulator/dryer and line?
Click to expand...

As always jrichker has you covered, but if you replaced the compressor before, and then charged it with 134a without flushing or changing anything else, you might have some problems down the road with the compressor or other parts. If that is what was done, you might want to have a shop flush the compressor. This is not something I suggest that you do since you need to know how to do it and what to look for.

The 134a and R12 are not compatible refrigerants, especially the oils used with them. What happens is the oils mix and create an acidic type fluid that eats at the seals. Which is why I suggest flushing the compressor, but it is not done with flushing fluid or mineral spirits, it is done with fresh oil. If it were mine, I would spend the extra and have a qualified shop do it. By the way the compressor failure I speak of is called "Black Death" it is just that the fluid turns black from eating the seals. Do a google search for it or look at a good AC forum, ackits.com.
 

808Gt

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backfocus said:
As always jrichker has you covered, but if you replaced the compressor before, and then charged it with 134a without flushing or changing anything else, you might have some problems down the road with the compressor or other parts. If that is what was done, you might want to have a shop flush the compressor. This is not something I suggest that you do since you need to know how to do it and what to look for.

The 134a and R12 are not compatible refrigerants, especially the oils used with them. What happens is the oils mix and create an acidic type fluid that eats at the seals. Which is why I suggest flushing the compressor, but it is not done with flushing fluid or mineral spirits, it is done with fresh oil. If it were mine, I would spend the extra and have a qualified shop do it. By the way the compressor failure I speak of is called "Black Death" it is just that the fluid turns black from eating the seals. Do a google search for it or look at a good AC forum, ackits.com.
Click to expand...



aww man yeah thats what i did but didnt think of the oil part I just put like 1 or 2 cans of oil before chargeing with freon...

well before I changed the compressor the system was already retro fitted with r134a before and then i just changed the compressor out, was happy that it worked and got a/c working !! I had it checked before from an a/c shop but charged me about 2000 :-( bt was like F that I can do it and jus have them re-charge it...

hmmm so my plan is change everything install it and take it to a shop to recharge it, should I tell them that I bought new components? or just tell them to check the system?
 
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