A/C system questions 99 4.0 OHV
#1
01-22-2023
A/C system questions 99 4.0 OHV
When I bought my truck I was told the AC compressor had noise and it had been suggested the previous owners replace it. When I pulled the system apart, I noticed age cracks on the rubber for the hoses so I plan to replace them. Given the previous owners had the system drained and left it unused, I'm guessing they had leaks along with the compressor problem.
Since I will be replacing the compressor and hoses, should I just go ahead and replace it all? I can do without A/C here in NC so I can buy and install the parts as I can afford them.
I already plan to also replace the blend door actuator because it is an inexpensive part that is a PITA to get to with interior installed. I had both an '02 & '05 Explorer that the actuator stuck on and I'd rather replace a functioning part with nothing in my way than replace it broken and have to work around interior parts. Should I replace anything in the heating system like the core or resistor?
Cost of replacing parts is less important to me right now than increasing the life of my truck. I can still work right now (disabled) and have around $200/month I can put into making her last as long as possible.
Since I will be replacing the compressor and hoses, should I just go ahead and replace it all? I can do without A/C here in NC so I can buy and install the parts as I can afford them.
I already plan to also replace the blend door actuator because it is an inexpensive part that is a PITA to get to with interior installed. I had both an '02 & '05 Explorer that the actuator stuck on and I'd rather replace a functioning part with nothing in my way than replace it broken and have to work around interior parts. Should I replace anything in the heating system like the core or resistor?
Cost of replacing parts is less important to me right now than increasing the life of my truck. I can still work right now (disabled) and have around $200/month I can put into making her last as long as possible.
#2
01-22-2023
The condenser, in front of radiator, is the most common leak point in vehicle AC, and an expensive part, about same as compressor for cost, if not more
Evaporator, inside heater fan box, is less likely to leak but can
Evaporator and condenser are the 2 parts that are repeatedly heated up and cooled down, which causes their thin metal parts to expand and contract, which can cause seams to fail, and leak
Hard to guess on hoses, cracks in the outside rubber coating don't mean much, so judgment call, but the O-rings do need to be changed
I would not install the new parts until you have all of them ready to go, buy them and store them until you have all the parts you need
Heater core on a 1999(1995 and up) is very hard to swap out, best bet is to flush it with garden hose in BOTH directions, you can refill it with hot water/CLR or hot water/vinegar wait 20min then flush again, in both directions, repeat as you see fit
Coolant has anti-corrosive chemicals that last 2 years(green) or 5 years(red/yellow) that protect the metal in cooling systems
Radiators and heater cores can get a few blocked passages over time, which in itself is not a big deal, the bigger deal is that fresh coolant with the anti-corrosive chemicals can no longer circulate passed those metal parts to protect them, so they will start to corrode
And on ANY vehicle, you should reverse the heater hoses every 2 years or so, to reverse the flow thru the core, i.e. back flush it while you drive, don't have to drain coolant, just swap hoses around at firewall
Evaporator, inside heater fan box, is less likely to leak but can
Evaporator and condenser are the 2 parts that are repeatedly heated up and cooled down, which causes their thin metal parts to expand and contract, which can cause seams to fail, and leak
Hard to guess on hoses, cracks in the outside rubber coating don't mean much, so judgment call, but the O-rings do need to be changed
I would not install the new parts until you have all of them ready to go, buy them and store them until you have all the parts you need
Heater core on a 1999(1995 and up) is very hard to swap out, best bet is to flush it with garden hose in BOTH directions, you can refill it with hot water/CLR or hot water/vinegar wait 20min then flush again, in both directions, repeat as you see fit
Coolant has anti-corrosive chemicals that last 2 years(green) or 5 years(red/yellow) that protect the metal in cooling systems
Radiators and heater cores can get a few blocked passages over time, which in itself is not a big deal, the bigger deal is that fresh coolant with the anti-corrosive chemicals can no longer circulate passed those metal parts to protect them, so they will start to corrode
And on ANY vehicle, you should reverse the heater hoses every 2 years or so, to reverse the flow thru the core, i.e. back flush it while you drive, don't have to drain coolant, just swap hoses around at firewall
Last edited by RonD; 01-22-2023 at 09:02 AM.
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Glaze77 (01-22-2023)
#3
01-22-2023
Replace everything that is suspect at SAME time. Espcially since its not charged now and there is no dye in the system to show you were the leak was. If you see evidence of metal shavings or black crud, EVERYTHING should be replaced. Rock Auto has good pricing.
Rock auto has both sets of hoses under $70. The condensor, ac compressor, o rings, pag oil, orffice tube, and drier/acculumlator can be had for less than $250 from rock auto in the combo kit.
You can take a chance and not replace the evaporator if there is no signs of damage or existing leaks. And, as long as there are no metal shavings or black crud in the system. Carefully pull the orffice tube out without nicking the inner tube, this will show you how contimated the system was.
Since your located up north, you can get away with the condensor in the kit. For those of you in the south, I would recommend the condensor by CSF, Motorcraft, APDI, which have a denser fin layout for more efficient operation.
If your doing the repair yourself, make sure you add the apporipiate amount of PAG46 oil, pull a good vacuum for a few hours with no leak down, and add the appropiate amount of r134 while measuring vent temps and low/high pressures while factoring in your humidity level/temps of outside air. https://www.autoacforum.com/ is a great resource for process.
Rock auto has both sets of hoses under $70. The condensor, ac compressor, o rings, pag oil, orffice tube, and drier/acculumlator can be had for less than $250 from rock auto in the combo kit.
You can take a chance and not replace the evaporator if there is no signs of damage or existing leaks. And, as long as there are no metal shavings or black crud in the system. Carefully pull the orffice tube out without nicking the inner tube, this will show you how contimated the system was.
Since your located up north, you can get away with the condensor in the kit. For those of you in the south, I would recommend the condensor by CSF, Motorcraft, APDI, which have a denser fin layout for more efficient operation.
If your doing the repair yourself, make sure you add the apporipiate amount of PAG46 oil, pull a good vacuum for a few hours with no leak down, and add the appropiate amount of r134 while measuring vent temps and low/high pressures while factoring in your humidity level/temps of outside air. https://www.autoacforum.com/ is a great resource for process.
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RonD (01-22-2023)
#4
01-26-2023
I'm in the south and found this condenser on Ebay. Part is compatible by Ford OEM part # cross reference. My truck is 4WD and does seem to have the off-road package since it has the chrome bumpers, 4.10 axle, factory tow hooks, etc. Anyways, does this seem a good deal?
https://www.ebay.com/itm/37231431763...mis&media=COPY
https://www.ebay.com/itm/37231431763...mis&media=COPY
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