Just a little compressor seizure???

[CraigK]

Tell me I didn't screw up terminally (for my compressor).

The compressor was working fine, but the system had a leak and would not hold freon (94 Explorer, not the BII). So I replaced the (leaking?)condenser, high pressure line to and from the compressor (one piece), the accumulator, and swapped out the orifice tube. Then sealed the system up.

I ran a compressed air/venturi type vaccuum to evacuate the system for ~1/2 hour (instructions say run 10 min), so I had at least some, if not complete, air removal.

Then I added one can of "Arctic Freeze" R-134a, which has 11 oz. R-134a, and 1 oz. oil. Everything was A-OK, and the compressor was cycling with increasing time periods as the R-134a was taken into the system (~20 minutes). The hissing leak seemed to be gone.

Then I set up the second can of the same stuff, and again, everything A-OK for a while, with compressor cycling with increasing on times, and some actual cooling of air. When the second can added enough freon to keep the compressor on, it ran 100% for about 2 minutes then began a HORRIBLE SCREECHING. This appears to be a compressor seizure. The compressor is VERY HOT to the touch, and appears to be seized up. Crap.

Questions:

Is the compressor likely to ever run again after it has cooled down??? Any special procedure to help this?

Oh yeah . . . What type of OIL should I add (PAG or Ester, both seems to be for R-134 systems???) Where should I add it to get to the compressor in a hurry? Into the accumulator? How much?

Any help appreciated. I have a long hot drive to make this weekend.

CraigK

 

[adsm08]

Did you ever add any oil to replace the oil that was removed with the replaced components? If not, you effed up and I wouldn't really count on that compressor being any good anymore.

Never ever ever add ester or mineral oil to an R134a system. PAG only.

 

[CraigK]

As feared, compressor is still siezed this morning. Removed it, and no debris or even discoloration visible anywhere in system.

I have a new compressor and PAG 46. Compressor is "pre-oiled" with PAG. How much PAG to system total? I'm adding an additional 1-2 oz to the compressor, but how much total for this system? I have a 7 oz bottle. Should I dump the other 5-6 oz into the accumulator, or is this too much?

Thanks.

Craig

 

[4x4junkie]

7oz total PAG-46 for a system using the FS-10 compressor (I usually put 4-5oz in the comp, the rest can go in the accumulator).

I suggest flushing out the entire system with solvent and change the orifice before you put the new compressor on. Almost guaranteed it left some debris in there which has the potential to ruin the new compressor as well (search for "Black Death").
If bad enough, you may need to change the condenser coil as well (sorry if this sounds extreme, but to keep the A/C working reliably after a compressor failure, it's what you have to do)

Also, unless your shop compressor is able to maintain 110 or better PSI the entire time while operating your little venturi-type vacuum pump (very few can), those things will not pull a good vacuum on your system. I would invest in a vane-type pump if so (vacuuming the system with the engine warm can further assist moisture removal as well).

http://www.harborfreight.com/two-stage-3-cfm-air-vacuum-pump-66466.html
http://www.harborfreight.com/25-cfm-vacuum-pump-98076.html

 

[shane96ranger]

I suggest flushing out the entire system with solvent and change the orifice before you put the new compressor on.

This is great advice. I wish I would have done this before I put the compressor on my Explorer fifteen years ago. I wound up replacing everything afterwards.

 

[adsm08]

I suggest flushing out the entire system with solvent and change the orifice before you put the new compressor on. Almost guaranteed it left some debris in there which has the potential to ruin the new compressor as well (search for "Black Death").

Black death is actually when the rubber in the lines starts to disintegrate, but yeah, a flush a new drier and a new orifice tube is the ONLY way to avoid a repeat. There are a few lines that will need replaced as well, anything with a muffler on it as debris gets caught in the baffles and can't effectively be flushed out. I know it's not cheap, but it is the only way to do it right.

 

[CraigK]

Thanks for your comments guys. Still have a problem, and would appreciate insight based on experience and the symptoms and facts.

Symptoms:
- will not accept more than ~1 11 oz can of R-134a (should take double this).
- very minimal cooling
- pressure gauges read ~105-110 psi on both high and low sides when running
(I don't really know how to read these gauges)

Note:
- NO DEBRIS in lines or orifice tube filter
- VERY CLEAN internally (all new parts except evaporator)
- had a family of mice living in my glove box and behind/underneath dash

Possible Issues:
- still too much air in system? (I vented the first R-134 fill when hot and refilled to attempt to purge more air)
- too much oil in system? (added 6 oz + 6 oz in compressor, but leaked out several oz during installation)
- evaporator area is plugged with mouse-house crap and heat transfer and cooling/evporation are not happening properly

Which of these possible issue scenarios is most consistent with the symptoms?

It looks to be a royal PITA to get at the evaporator. Can the evaporator case be unscrewed and pried open enough to look inside by removing the easily accessible bolts holding the two sides of the case together?

Thanks.

 

[5literbeater]

If your pressures are the same on both high and low your compressor is not pumping. This would also allow for you to not add more freon because the pressure in your bottle and system are equalized. Is the clutch engaged? If so, sounds like you got a bad compressor.

 

[adsm08]

~110 PSI sounds like equalized static pressure with the engine bay near running temp (somewhere around 170-200*). You don't have your gauges in some sort of by-pass mode do you? A few of the fanicer sets I've seen have a by-pass and it will make that happen.

Assuming the compressor is engaged, the other option is that the orifice tube is missing or has a huge hole punched in it.

 

[5literbeater]

Adsm08 could be right. I was just thinking about the blown out orfice. I forgot to say that. Good call.

 

[CraigK]

Okaaaaaay . . . Instrument/Operator Error

Harbor Freight gauges. Have a yellow middle line that is supposed to be for servicing??, but must connect the sides, because if I shut off the high side, the low reads ~25 psi. If I then shut off the low side, the high side reads ~190 psi.

What should I be looking for, all warmed up, fully charged with the compressor running 100% of the time? Thanks again.

BTW, I got more freon in, and cooling has increased.