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George H.
George H., Hyundai Technician
Category: Hyundai
Satisfied Customers: 18538
Experience:  Hyundai Gold certified, ASE Master tech 15+ years
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I hope you are OK. Please, let me know how to disconnect the

Customer Question

Hello, George: I hope you are OK. Please, let me know how to disconnect the aC lines at the evaporator end. The hex bolts are stuck, and I would not like to round them or break them. Any trick to disconnect the lines so I can flush them? I am replacing
the AC compressor. Also, what are the low and high side pressures???
Submitted: 1 year ago.
Category: Hyundai
Expert:  George H. replied 1 year ago.

Hello I will help you with your question,

I use a drill to take the heads off the bolts on the H block or a die grinder and just cut through the side of the block. Either way you have to replace the block and if the stubs of the bolts are stuck in the flange of the evaporator (about 1/2 the time) you need to replace the evaporator as well.

Is there evidence that the compressor came apart? Metal in the inlet to the H block? If not I suggest not flushing the cor.

Pressure on a R134a system should be about 200 high and 30 - 45 low depending on the ambient temperature.

Please let me know how I can help

Thank you

Customer: replied 1 year ago.
Please, pardon my ignorance. What is the H block. Also, to make sure we are talking about the same bolts, I am referring to the ones that are located on the engine compartment side (on the fire wall's passenger side of the vehicle), there seem to be three hex bolts attaching both A/C lines to the expansion valve which in turn seems to be connected to the evaporator.
Expert:  George H. replied 1 year ago.

There are three bolts on the H block (the expansion valve you can see on the engine side where the AC lines connect). You will have to remove the one holding the lines to the block and you might be able to grab the head of that one with small vise grips then two recessed ones that hold the block to the evaporator. If those won't turn the block will have to be cut to get to the evaporator side of the lines.

Which Hyundai are you working on?

Customer: replied 1 year ago.
2006 hyundai Santa Fe 3.5 V6 front wheel drive
Expert:  George H. replied 1 year ago.

That makes it tight to either drill or cut the block when the bolts seize up which is just about every time.

The block is aluminum and the bolts are steel and the block sweats from condensation all the time so it is a recipe for corrosion.

All I can say is do what you can to either cut the bolts or grab them with vise grips. You cannot heat them. Is there evidence that metal or grey sludge is in the lines or the block?

Customer: replied 1 year ago.
As a matter of fact the bolts can be described as follows:There are two horizontally aligned on the upper side of the rectangular expansion valve. These two are hex bolts (concave), and have a round head. In the middle of the rectangularexpansion valve (just about a little below the two bolts just described, there is another smaller (very small) hex bolt.
Expert:  George H. replied 1 year ago.

The smaller bolt holds the lines to the H block and the two others hold the block to the evaporator. To flush the evaporator you will need to remove all three.

Customer: replied 1 year ago.
No, there is no evidence of gray matter. Could some bolt extractors work? Please, see below:
http://www.walmart.com/ip/Irwin-394001-Bolt-Grip-5-Pc.-Base-Set/15107535
Also, at what psi should an air compressor be to flush the lines, and the evaporator? Is the condenser on this 2006 Hyundai 3.5 (V6) flushable?
Expert:  George H. replied 1 year ago.

You don't really have room to use bolt extractors in there.

The condenser is parallel flow so you can't flush all of it. If there is evidence of internal damage to the compressor you replace it and the drier, if no evidence of sludge or metal leave it all alone and just change the drier and the compressor.

I have a set of those extractors from Sears, they work if everything is right but a pair of Vise grips will do the same thing and fit in tighter spaces.

You say there is no metal or sludge I would just vacuum for 1 hour after installing the drier and compressor then let it sit for 15 minutes to check for leaks and if you still have a full 29" of vacuum fill it up and run it.

Let me know how I can help

Thank you

Customer: replied 1 year ago.
Thank you for your reply. Well, this is what I have done so far: I disconnected the low-side line at the condenser (front of the hood), with the lines attached to the evaporator, I used a flushing fluid (in a spray can) through the low-side line to flush the low-side a/c line, the evaporator, and the high-side line, my air compressor was compressing air into the lines at 90 psi, most of the UV dye that was in the system came out, I blew compressed air into the low-side line for as long as I saw UV dye getting out on the other end (the high-side line), but I cannot guarantee that the a/c lines and condenser are totally clean because of all the twists the the a/c lines have. With that said.... this was step # ***** in my A/C compressor replacement process. The second step was (as you just described) to vacuum the system. There was a vacuum of about 28 or 29 inches (below the zero on the low-side gauge), then I closed both valves on the manifold gauges (to read pressure on the lines), no leak at all because the vacuum was still at 28-29 inches. I then put in the refrigerant and the compressor started well, in 10 seconds it stopped working. The clutch began to slug, turning very slowly in short, irregular, intermittent intervals until...... I believe the clutch has gotten stuck.
Expert:  George H. replied 1 year ago.

Why are you replacing the compressor in the first place?

When you installed the refrigerant was it through the low side port? Did you turn the compressor by hand to move any oil and refrigerant through it to the high side?

Did you put oil in the low side port or the compressor?

Customer: replied 1 year ago.
Answer to the previous questions:
Why are you replacing the compressor in the first place?
The front seal was leaking badly. I was losing my refrigerant overnight. I will have the front seal replaced by a compressor repair shop.When you installed the refrigerant was it through the low side port?
Yes, always through the low-side port.Did you turn the compressor by hand to move any oil and refrigerant through it to the high side?
Yes, I turned the clutch 10 rounds by hand.Did you put oil in the low side port or the compressor?
The shop that sold me the compressor explained that the compressor had the oil already inside.
Expert:  George H. replied 1 year ago.

OK, if you were installing the refrigerant through the low side then it could have entered the compressor as a liquid which would lock and damage the compressor. See if you can turn it by hand.

At this point I think you do need to open the evaporator and both sides of the condenser so you can blow them clear, no need for flushing if all you had was a leak.

Let me know what you find, once you get the system blown clear put 1 ounce of PAG oil in the evap and another in the condenser. Turn the compressor by hand and if you have to install the refrigerant through the low side then run it in very slowly so you only have gas entering the system. Any liquid will destroy the compressor.

If the compressor you got was a "reman" then it could be junk out of the box. Most are. Only use a new compressor.

let me know what I can do to help

Than you

Customer: replied 1 year ago.
On this 2006 Hyundai Santa Fe 3.5, in order to open both ends of the condenser I would have to bring down the front bumper, or any other major part in the front bumper area, or is it an easy process to disconnect both ends of the condenser?
Customer: replied 1 year ago.
Also, where is the dryer (bag) of the condenser? Is it difficult to access (do I need to bring down any other components to access the dryer)?
Customer: replied 1 year ago.
I will continue to check for the answer to my last questions. Thank you.
Customer: replied 1 year ago.
Would it be necessary to remove the dryer (bag)?
Expert:  George H. replied 1 year ago.

The dryer is in the end of the condenser that is rounded, there is a plastic plug on the bottom of that rounded end. To remove the condenser you will have to remove the grille or get to the fasteners through the grille and disconnect the condenser from the radiator then pull it out the top.

Yes, anytime you replace a compressor you replace the dryer.