First of all, Happy Thanksgiving to all. I thought I could slip in a quick job before visitors arrived and decided to pull out the AC Orifice Tube to look for signs of Black Death. Having read up on this before I was able to undo the connections at pts A and B (thanks to whomever's picture I borrowed here):
Then I loosened up the clamp just to the left of this as shown here. The green arrow is the clamp and the red arrow is where the pipe bends up into whatever-that-cylinder-is:
Problem is the Tube is still held in place by both ends of this loop. There is about 1/16" clearance if that by trying to force the ends apart so the Tube will come out. It looks like the end on the Left should come out first but there is an unknown length of aluminum tubing extending inside.
The only other hold-down/clamp is maybe as shown here:
Is this the problem or should I be removing something else?
One more thing ... I swabbed the inside of the inlet/outlet tubes on the compressor using a Q-tip dampened with Throttle Body Cleaner. The one on the Left was pretty clean, lightly grey. The one on the Right was black as night:
Any predictions on what I shall see on the orifice tube?? It was the usual failure cascade ... had been driving and AC was 'ok' but not very impressive when the compressor seized and in a matter of moments the belt was totally destroyed, smoke pouring out of the engine compartment while I quickly pulled to the side and stopped.
[This message has been edited by Notorio (edited 11-22-2018).]
Is not clamped. The O-tube often jams and need an O-tube puller to get out. Forcing any other way can easily break and be harder to get out.
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
The tube on the left of the orifice holder tube goes to the evaporator in the heater box so it's not gonna move much. On the right side the metal tube connect (I think) to a hose that drops down behind/beneath the tub> I 'think' it's also clamped beneath the tub as well. While you 'can' get them apart in place like that, in the past I've removed the tub so I can get to the clamp on the right side. With that lot out of the way it's a lot easier to separate the parts. As Ogre say,s orifice tube is not clamped inside the holder, just a push fit. A pair of needle nose plies should get it out. Expect the mesh to be covered in metal particles and black gunge if you've really had black death. Only real fix is to replace all the hardware, compressor, evaporator (in the heater core), accumulator (the big silver bottle up front) AND the condenser (in front of radiator), plush flush out all the lines.
------------------ Anything I might say is probably worth what you paid for it, so treat it accordingly!
Your memory was correct: with the tub out the hold-down clamp is readily apparent. With that out then the joint gained clearance. With the joint apart on the driver's side just looking at the aluminum itself I could see 'oh no, that looks pretty black just by itself ... gasp ...'
With the needle-nose pliers and a hefty pull (visions of the tab breaking were dancing in my head) the filter came into the light of day. My immediate thought was 'I'll bet this qualifies for the worst-looking Black Death filter anyone on the forum has ever seen. Black Oblivion perhaps ? What's the verdict? Is it worth getting all the replacement parts and flushing until the cows come home? This looks pretty bad to me ...
------------------ hoop SCCA STL Integra '17 Grand Cherokee Trailhawk '13 Xc 60 T6awd 3 1st Gen Crx in Various states of Decay or Repair (for sale) '86 Fiero GT
The rubber veins or seals or something in the AC compressor disintegrate and get dispersed throughout the system. Don't know why really -- lack of oil? Eventually aluminum chunks are produced (I am amazed they make it all the way to the front of the car rather than settle out along the way) and the compressor seizes. Can anyone who really understands this chime in??
Black death is when the system gets low on refrigerant (or you don;t put enough oil in it when charging) so there's not enough oil flowing around the system to lubricate the seals of the compressor (the oil is suspended in the refrigerant). Just like a regular motor, no lubrication is bad. In this case the seals in the compressor pistons break up and form a black sludge with the remaining refrigerant that then gets distributed throughout the system. It usually ends up blocking the filter around the orifice tube which stops refrigerant flowing and you get no cold air, even though the system has a charge. It also gets into the condenser, accumulator and everything else in the system (all the pipes).
In addition, once the seals go completely, aluminum starts rubbing on aluminum in the compressor and bit of metal get distributed around the system too. If you see silver particles on the orifice filter then the compressor is dead too. Usually once the compressor dies like this, it siezes and your belt squeals untl it fails! The only real way to get it all out is remove everything and flush it but even that is not guaranteed.
You should also install a filter into the system after suffering black death in order to catch any remaining crap but there's not a lot of places to do that easily on the Fiero.
Originally posted by Notorio: What's the verdict? Is it worth getting all the replacement parts and flushing until the cows come home? This looks pretty bad to me ...
I see where you're from so A/C is probably more important than where I live. For me and how I use my Fiero (not a daily driver) and where I live (MI,) I would just live with 2 windows down at speed for my climate control. My A/C still works but windows down is mostly how I drive it anyway.
I will chime in, I have been messing with A/C HVAC systems for a while, I know a little bit... no expert though, it’s not my speciality. Yes, it is usually caused by the compressor, it’s a combo of ground metal or Teflon(?) and compressor oil and it’s near impossible to get all of it out. Back in the day Fords were famous for this. The only way I ever “cured” the problem for any significant amount of time was to change everything including hoses. Totally sucked and was costly. The problem was the little stuff left behind can, but not always, damage the new compressor and now more crap in the system. Some have gotten lucky. I haven’t been as lucky though. Just my experience so far..
You may get away with not replacing the evaporator (in the heater core box) as that's down stream from the orifice tube so you'd hope not too much gunge got through to it so it 'may' be possible to just flush it. The condenser in front of the rad though is up stream so any gunge was going through it it's way to the orifice. Looking at the orifice tube, you can imagine what the inside of the condenser looks like! As far as flushing goes, you can use mineral spirits which are a lot cheaper than proper flushing fluid, however they are very messy and leave an oily residue. Proper flushing fluid is much cleaner and any left behind/spilt readily evaporates so you are not left with the same mess as with mineral spirits. You can reuse the flushing fluid with care, just save the dirty stuff and filter it (several times) through paint filters, use two or three together. Do the bulk of the cleaning reusing like that then finish off with clean stuff so you can see by how dirty it gets (hopefully not at all) how clean your systems lines are. A flushing bottle works quite well to flush the system
------------------ Anything I might say is probably worth what you paid for it, so treat it accordingly!
When I bought the fiero it was suffering from black death. I tore everything apart. Did not replace hoses though. Made the biggest mistake getting a remanufactured compressor. Get a new one. Remanufactured compressors are crap. Flush the hell out of all the parts. I am going to check the orifice tube again when I have time to make sure nothing is still there as the hoses continue to degrade from what I have read about the dreaded black death. Good Luck it will work again!
My immediate thought was 'I'll bet this qualifies for the worst-looking Black Death filter anyone on the forum has ever seen. This looks pretty bad to me ...
Lol! How black is black? (Plus a few shreds from the compressor for dramatic effect...)
Originally posted by ltlfrari: As far as flushing goes, you can use mineral spirits which are a lot cheaper than proper flushing fluid, however they are very messy and leave an oily residue. Proper flushing fluid is much cleaner and any left behind/spilt readily evaporates so you are not left with the same mess as with mineral spirits ...
My thought was to flush multiple times with Mineral Spirits then flush out the Mineral Spirits with Proper Flush. What do you think of that plan??
I have been checking around for a new condenser (i.e. the part in front of the radiator) but have only been able to find lots of used ones, such as on Car-Part.com. When the time comes I'd get one there or start with a WTB post in the Mall. But how can anyone with a 'working' AC know the true status of it? It could be 75% of the way toward Black Death but how would we know? I guess at that point it might have a lot of dispersed rubber particles inside but should NOT have any aluminum trash yet. Yes? No?
It has been reported that the "Black Death" can be caused by improper conversion from R12 to R134a. The Oil that lubricates the system ( including the compressor) is suspended in the Refrigerant. R12 uses Mineral Oil, while R134a uses PAG oil. The two are incompatible. R134a will not transfer the mineral oil through the system, so if no new oil is introduced when a change is made, then no more oil gets to the compressor. Even if new oil is added, there is still the incompatibility of the oils. They gather in the accumulator, and reaction of the oils attacks the desiccant in the accumulator, causing it to get released into the refrigerant stream-- more gunk to deal with. Many of these Deaths are caused by the cheap Retro-fit kits at the auto stores. A connector and a can of R134a! Yes, it will work for a week or so, but.....
Proper flushing when doing a changeover is a must, as is replacing the oil in the system. I prefer to use Ester Oil for changeovers, as it is compatible with Mineral oil ( you can't get it all out, unless you replace everything). Also change all of the O'rings to the Green style. Older hoses also have larger "pores". Ther R134a molecules are smaller than R12, and will eventually weep through the hose, so a gradual "leak" will appear. Not a lot, maybe 1/4 to 1/2 a can per year. Newer hoses are called Barrier Hoses, and as stated prevent the R134a from escaping. Easier to change on some cars, but with the Fiero, I left them alone.
Originally posted by darbysan: The R134a molecules are smaller than R12, and will eventually weep through the hose, so a gradual "leak" will appear. Not a lot, maybe 1/4 to 1/2 a can per year. Newer hoses are called Barrier Hoses, and as stated prevent the R134a from escaping. Easier to change on some cars, but with the Fiero, I left them alone.
Now that I think about it I don't know what the PO had in the AC, R12 or R134a. How do I tell?
Larry, thanks for posting the Fierofiberglass link. He has a lot of interesting products there, including the condenser.
[This message has been edited by Notorio (edited 11-25-2018).]
If it's empty and you flush it, it doesn't really matter what was in before. You're gonna replace pretty much everything and put 134 in anyway. I seem to recall I got my condenser from Fiero Fiberglass.
Oh, and this is 'my' understanding of oil use. You may want to double check as I I'm doing this from memory and the old grey stuff ain't what it used to be !
R12 - Ester oil R134a as ORIGINAL INSTALL - PAG oil R134a as a conversion from R12 - POE oil
But like I say, double check that, not sure if I am right or not.
------------------ Anything I might say is probably worth what you paid for it, so treat it accordingly!
Originally posted by Notorio: Where did you find a new one??
I got a new compressor and accumulator from Advance Auto Parts, they're also on RockAuto, and a new evaporator core ('84 specific) from www.obsoleteair.com (found on Ebay along with others)
Originally posted by da.slyboy: For an extra safety, I also added an in-line filter in case my intense flushing missed something.
Where did you get the filter and fittings? Where did you insert it into the system? Any chance you have a picture?
quote
Originally posted by David Hambleton: I got a new compressor and accumulator from Advance Auto Parts, they're also on RockAuto, and a new evaporator core ('84 specific) from www.obsoleteair.com
Per suggestion above I will probably just flush the evaporator core.
[This message has been edited by Notorio (edited 11-27-2018).]
Oh, and this is 'my' understanding of oil use. R12 - Ester oil R134a as ORIGINAL INSTALL - PAG oil R134a as a conversion from R12 - POE oil
R12 is definitely Mineral oil. The POE oil you mention as an R134a conversion oil is the Ester Oil I mentioned. The PAG oil is the oil that is not compatible with Mineral oil (R12)
When I DO eventually get to this task I was planning on flushing with Mineral Spirits first, several times (it is cheap), then one of the various recommended AC flushes.
I don't think mineral spirits is such a good idea either. I used it to clean oil of my engine so if not completely removed parts that need lubricated will probably have a oil issue. I am in the HVAC industry for 38 years now and we use a filter drier in the liquid line to catch any trash and moisture left behind. I don't no if automotive industry has that other than that orifice tube drier. If you get enough crap out when flushing, checking or changing that again after running would be a good idea if you are not replacing the evaporator or condenser.
I used NAPA AC flush solvent when I did my AC, it's 13.49 a can. The MSDS says it's n-Heptane and Isopropyl alcohol.I used 4 cans to flush the lines and evaporator, I was amazed at how much crap came out of the lines. I put in a new condenser from Fiero Fiberglass.
Note that flushing can remove oil in old rubber hoses and using R134 can leak thru the old rubber. Old R12 Oil coating in a hose will act as a barrier to reduce/stop R134 leaking. Flushing will remove most to all mineral oil from R12 systems.
Is why you replace old hoses w/ new Barrier Hose. Is not just EPA rules but old hose was never made to keep R134 and others in the system.
Many hydro hose shops can replace old hose on most hardware. call them. Take pictures just how they are made before sending to hose shop. Some hose sets matter just how they are made to eliminate twisting when install. Engine to body/frame hose set is 1 of these.
Originally posted by theogre: Note that flushing can remove oil in old rubber hoses and using R134 can leak thru the old rubber. Old R12 Oil coating in a hose will act as a barrier to reduce/stop R134 leaking. Flushing will remove most to all mineral oil from R12 systems.
Is why you replace old hoses w/ new Barrier Hose. Is not just EPA rules but old hose was never made to keep R134 and others in the system.
Many hydro hose shops can replace old hose on most hardware. call them. Take pictures just how they are made before sending to hose shop. Some hose sets matter just how they are made to eliminate twisting when install. Engine to body/frame hose set is 1 of these.
I have no data to support this (should I be running for Congress?) but I would guess that only 10 - 20% of people converting to R134 get the hoses changed ...
Just a bone to toss out here, since you can get R12 on line, why not flush the system, replace the mineral oil, and and refill to original specs. The hoses won't leak due to the incompatibility issue. Just wondering what people think about that ...
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(Plus a few shreds from the compressor for dramatic effect...)_2.jpg)
