Air Conditioning Problem
armallard
07-10-2009, 04:20 PM
I have a question about ac on a 1998 4.3 vortec 4 w drive i know my compressor is bad its leaking freon the system is empty i guess its blowing hot air i do have another compressor can i just change them out and re charge the system? or am i jumping ahead of myself Any info would be appreciated:uhoh:
old_master
07-10-2009, 06:14 PM
It depends on how good of a job you want to do. If the system is empty, the accumulator has been exposed to humidity and the desicant inside is saturated. The only fix is to replace the accumulator. As a precaution, the fixed orifice tube should also be replaced. Make sure the compressor has the correct amount of the correct oil in it. Evacuate the system for a minimum of one hour, then partial charge with R134a refrigerant and leak test the system. If no leaks, finish the charge. That is the proper way to do it however, it's your vehicle and you can replace just the compressor and recharge if you like.
TallyMatt
07-11-2009, 08:45 AM
I think he needs a little more info than that..... I am in the middle of changing my own in a 2000 S-10 w/ 4.3L V-6... I am no pro by any means, but here's my two cents....
You will need to buy a lot of equipment and parts to do the job properly yourself.... and a lot of time....
(all at Harbor Freight if you have one nearby)
2-stage Vacuum Pump $150
Manifold Gauge Set $50
Cut-off valves for the cheapo gauges to allow easy swapping from vacuum pump to recharging cans
New:
Compressor $250
Accumulator $30
Orifice Tube $2
O-ring replacement set $10
R134a w/ UV Dye, 3 cans, $20
Blacklight (for leak checking)
Possibly:
New Condenser $150
New Evap $150
Might consider:
New low pressure switch $17
New compressor cut-off switch $30
Cleaners:
AC Flush
Radiator Flush (might as well since you may have to pull the rad to get out the old condenser)
Tools:
Good set of end-wrenchs in bigger sizes, 22MM and large and 3/4" and larger (up to 1 1/4 I think) You will need metric and SAE
Two sets of ratchets (10 and 13mm)
Several ratchet extensions and a 90 degree swivle
Two adjustable wrenches larger than 1"
Jackstands, jack and tire iron
Air compressor to clean out reusable parts (with appropriate end tools)
drain pans for radiator fluid, oil/tranny fluid from radiator
A spanner wrench for your new compressor (to turn it over BEFORE first use)
It really depends on what happened to the "old" compressor. If you are sure the system has NO charge on it (e.g. use your new manifold gauges and check), go ahead and remove the accumulator from the evaporator (do not discard, it has switches you may want to reuse). Next, underneath where the accum. was, locate the evaporator tube and open the connection there (where tub and evap connect). Inside the evap. inlet tube, there will be a plastic stick/filter called the orifice. Carefully pull that out of the evaporator and inspect it. If its clogged with metallic looking particles (metal from a blown compressor), you should replace all AC components. If you don't have cash for that, you could try to flush the metal particles from your other components (hoses, condenser, evaporator), but you might not get it all -- and thus destroy you brand new compressor.
If you replace the condenser, you have to pull the rad. If you do that, you'll need to change your coolant and you might as well flush your cooling system while your at it. Consider replacing your thermostat and/or water pump too since you'll have everything off.
If you replace the evap, you have to pull pass. side tire, wheel well, battery, plastic coolant surge tank, computer, loosen hood on pass. side, take off pass. side front quarter panel (in other words, several hours and you need a buddy to hold things). The evap housing has several nuts in very hard spots to get (hence the buddy and the ratched 90 deg. jobber).
In short, if you have time and patience, YES, you can do it.... but I'm 4 weeks into my job. I've had bad encounters purchasing parts via the Internet. Stick to your local shops, but even they get it wrong. Have returned one incorrect switch and was told by another they didn't have spanner wrench when they did.
But.... I'm $750 invested, had a brand new AC system and I've still saved $500 from what the shop wanted to replace just the evaporator.....
You will need to buy a lot of equipment and parts to do the job properly yourself.... and a lot of time....
(all at Harbor Freight if you have one nearby)
2-stage Vacuum Pump $150
Manifold Gauge Set $50
Cut-off valves for the cheapo gauges to allow easy swapping from vacuum pump to recharging cans
New:
Compressor $250
Accumulator $30
Orifice Tube $2
O-ring replacement set $10
R134a w/ UV Dye, 3 cans, $20
Blacklight (for leak checking)
Possibly:
New Condenser $150
New Evap $150
Might consider:
New low pressure switch $17
New compressor cut-off switch $30
Cleaners:
AC Flush
Radiator Flush (might as well since you may have to pull the rad to get out the old condenser)
Tools:
Good set of end-wrenchs in bigger sizes, 22MM and large and 3/4" and larger (up to 1 1/4 I think) You will need metric and SAE
Two sets of ratchets (10 and 13mm)
Several ratchet extensions and a 90 degree swivle
Two adjustable wrenches larger than 1"
Jackstands, jack and tire iron
Air compressor to clean out reusable parts (with appropriate end tools)
drain pans for radiator fluid, oil/tranny fluid from radiator
A spanner wrench for your new compressor (to turn it over BEFORE first use)
It really depends on what happened to the "old" compressor. If you are sure the system has NO charge on it (e.g. use your new manifold gauges and check), go ahead and remove the accumulator from the evaporator (do not discard, it has switches you may want to reuse). Next, underneath where the accum. was, locate the evaporator tube and open the connection there (where tub and evap connect). Inside the evap. inlet tube, there will be a plastic stick/filter called the orifice. Carefully pull that out of the evaporator and inspect it. If its clogged with metallic looking particles (metal from a blown compressor), you should replace all AC components. If you don't have cash for that, you could try to flush the metal particles from your other components (hoses, condenser, evaporator), but you might not get it all -- and thus destroy you brand new compressor.
If you replace the condenser, you have to pull the rad. If you do that, you'll need to change your coolant and you might as well flush your cooling system while your at it. Consider replacing your thermostat and/or water pump too since you'll have everything off.
If you replace the evap, you have to pull pass. side tire, wheel well, battery, plastic coolant surge tank, computer, loosen hood on pass. side, take off pass. side front quarter panel (in other words, several hours and you need a buddy to hold things). The evap housing has several nuts in very hard spots to get (hence the buddy and the ratched 90 deg. jobber).
In short, if you have time and patience, YES, you can do it.... but I'm 4 weeks into my job. I've had bad encounters purchasing parts via the Internet. Stick to your local shops, but even they get it wrong. Have returned one incorrect switch and was told by another they didn't have spanner wrench when they did.
But.... I'm $750 invested, had a brand new AC system and I've still saved $500 from what the shop wanted to replace just the evaporator.....
mike2004tct
07-12-2009, 07:54 AM
I changed the compressor on my daughter's '96 Sunfire a few years back.
Got a salvage yard unit, bought a refill kit from AutoBarn that contained a can of oil, and 3 cans of R134a.
Unit worked fine for the two years after I did the replacement. Ended up taking the whole car to the salvage yard (bad motor, trans, CV shafts, 200k miles)
Total cost: ~$110.00.
Got a salvage yard unit, bought a refill kit from AutoBarn that contained a can of oil, and 3 cans of R134a.
Unit worked fine for the two years after I did the replacement. Ended up taking the whole car to the salvage yard (bad motor, trans, CV shafts, 200k miles)
Total cost: ~$110.00.
b1lk1
07-12-2009, 10:45 AM
I changed the compressor on my daughter's '96 Sunfire a few years back.
Got a salvage yard unit, bought a refill kit from AutoBarn that contained a can of oil, and 3 cans of R134a.
Unit worked fine for the two years after I did the replacement. Ended up taking the whole car to the salvage yard (bad motor, trans, CV shafts, 200k miles)
Total cost: ~$110.00.
This is what I would do.......
Got a salvage yard unit, bought a refill kit from AutoBarn that contained a can of oil, and 3 cans of R134a.
Unit worked fine for the two years after I did the replacement. Ended up taking the whole car to the salvage yard (bad motor, trans, CV shafts, 200k miles)
Total cost: ~$110.00.
This is what I would do.......
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