Engine Size: 2.8L
Refrigerant Type: R134
Ambient Temp: 85
Pressure Low: 21-35
Pressure High: 250-300
Country of Origin: United States
I searched and found a little information but I need some input here.
I installed a new HR6/hose assembly and accumulator in my Fiero. Before installation I put 5oz of oil in the compressor, 2 in the condenser and 1 in the accumulator. I removed the evap and condenser and flushed, flushed, flushed and blew, blew, blew. Same for all lines. One difference from before is I installed the Ford Blue orifice.
When I oiled the compressor I got out my nifty tool and spun it 20 times to distribute the oil. It was nearly impossible to turn but I was able to do it finally. I haven't felt one this tight before. I figured since it's new, it's probably normal.
I installed it, vac it all down and charged it (R134). The performance is great! I can get 45F air on a 90+ day. Pressures are good. Cruising I see 220-250 (higher if I come to a stop but not over 300-310). I charged as close as I could to the bottom of the vent temps and have 30oz in the system (stock R12 spec was 40oz).
After about an hour or so of use I started hearing a squeal like a belt slipping. I checked the belt, it's tight but the noise is still there. It comes and goes like something is grabbing (every couple of seconds) . I tried to spin the compressor with the clutch tool and it's still as tight as when I put it in. Some effort is one thing but this one seems wrong.
I am thinking either the compressor had a problem from the box or I starved it of oil somehow. When I was charging it sounded fine but after that hour of running it started making a squealing and rattling noise. To me it sounds like a bearing.
Any idea how to troubleshoot this further? I was thinking of discharging the system and checking the orifice for debris.
Any thoughts appreciated.
Edited: Tue July 22, 2008 at 11:19 AM by terryk
Would be a little concerned about what the high side pressure is when the clutch is locking up. Fiero do not have the greatest air flow and you may be getting a compressor lock up issue do to a high pressure. If the pressures is no higher than 325 when it is locking up. There is a chance it's a bad compressor but I would rule out other things first.
I took some time and watched it. It's locking up so I am guessing I have a paper weight.
Any idea what I might have done wrong? Plenty of oil, freon, charge.......
Off to go shopping!
Edit: During this lockup the pressure was 200-220. It will spin nice and free for 30 seconds or so then start the lock up but the pressure never gets that high (300-ish). It's 70F outside right now.
Edited: Sun June 01, 2008 at 3:36 PM by terryk
Why can't you return the compressor if it's defective?
I was trying to do a bit of troubleshoot before I called ACKits for an RMA.
If I dorked it up I want to know how that's all.
What's the part number we sent you? Don't think it was staved of oil as the oil moves around pretty quickly. I don't like pumping the oil out of the compressor as you may have done though. We spin our compressors on the bench then drain the shipping oil before add new and installing the compressor. You are on the verge of what I consider a high pressure issue. Not a fan of converting this vehicle. Might see what happens if you reclaim an ounce or two of refrigerant.
I've read on here some of the reluctance to convert the Fiero but I've done several and this is the first one to give me any trouble. I might consider going back to R12 if you suspect this problem is related to R134.
You think those pressures are too high for the compressor? With 30 Oz I've never seen the high side go north of 300 but during today's testing I never saw over 220 although the compressor was locking up so I had to keep turning off the clutch lest I wipe out the belt. It's a pretty horrible sound but if it's turning it is blowing cold air.
The part number is 000207CP - R/B Comp W/CL HR6 1GR.
I'll pull a couple of OZ out and see what happens.
Edited: Sun June 01, 2008 at 5:32 PM by terryk
Best as I can measure (using a vacuum tank and venting into the tank, I pulled out 3-4 oz (this isn't science).
The compressor is still locking up. I looked blew some of the freon into a filter and it's got lots of silver in it. I'll pull it, drain the oil and see what it looks like.
I suggest getting you another compressor. Give the guys a call Monday for an RMA.
I will and thanks for the info! I'd like ACK to look at it and tell me what they think before I do anything else.
Edited: Sun June 01, 2008 at 6:58 PM by terryk
I flushed my system today in preparation for the recharge and when I drained the accumulator, there was 5oz of oil in it.
Is it normal for 5oz on an 8oz system to be in the accumulator?
Seems like a lot of oil in the accumulator to me. Yes they will retain a fair amount but 5 ounces seems like a lot to me. Could be a good reason why the last compressor failed!
A sure sign of being "oil-logged"&....
The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......
Could either TRB or GM Tech tell me what those comments mean? I'm trying to figure out what went wrong.
With the data provided it sounds like too much oil was in the system. GMTech can explain his comments, but it has me wondering if the change in OT size is part of the problem?
I was thinking the same thing (not that I have a clue). Is it possible the there wasn't enough flow to pull oil through? At the same time, it cooled like nobody's business.
Tim, I sent you an email to read at your convenience.
Edited: Sat July 05, 2008 at 10:16 PM by terryk
So I keep hearing this voice "If you can use R12 it will work better". Not quite a Field of Dreams voice, but more like my mom or TRB.
If I was to switch back to R12 I would assume I need to use 525 mineral oil. It's obviously had PAG 150 and R134 in it though.
I've flushed everything with Hecat Flushing Agent (TM) by flooding the part and letting it sit for an hour and then flushing more through followed by compressed air for 30 minutes.
Is that sufficient a flush to switch back to mineral oil or am I courting disaster?
The reason I ask is that I never bothered looking in the "blue box" in the garage marked Fiero stuff and what do I find... several cans of the good stuff.
Is there a different oil I I should use if I use the R12? Should I stick with PAG 150 and R134?
I would use polyol ester as it compatible with R-12 or R-134a. I do not like
PAG as it is more hygroscopic (absorbs water) than ester oil and if moisture
gets in the system it will introduce corrosion.
BAV Auto 100 is a good choice to use.
What year is this? Last time I worked on a Fiero and that was a 1984 and kind of recall never again. A guy really needs a lift to work on these things plus a reliable helper. Recall having problems hooking up the gauges and really a PITA for changing over from vacuum to charging. Corrected that by hooking the pump to the blue hose, R-12 shut off to the yellow hose, and the red to the high side, then drawing a deep vacuum first with the lo side open, closing that, then opening the R-12 valve on the tank to the high side trying to get enough refrigerant into the system for good positive pressure. Then switching the blue back to the port, purging again, then charging by pressures at 1,500 rpm.
With high hi side pressures, you could well have air in the system, these cars weren't really made for servicing.
I've been working with Fiero's for over a decade. They are very easy to work on actually. If you know GM FWD cars, you can handle a Fiero.
Right now I am asking about the flip back to R12.
ps., yes 84's had some odd thngs but they were redesigned in 85 and they couldn't be easier for servicing the AC.
Edited: Tue July 08, 2008 at 11:36 AM by terryk
R-134a conversions purely have been and experimental thing that varies from vehicle to vehicle and if someone who did a conversion on your year, make, and model, that would be great to know. In my case, R-134a wasn't even on the market yet.
But the key is to be able to put enough R-134a in to get satisfactory cooling without the high side blowing up through the roof, if that can't be done, have to convert to better fans and perhaps a parallel flow condenser and try it again. In general, it's best to use the refrigerant the AC system was designed for, but that is only practical if you can get your hands on R-12. Neither GM nor the EPA cares about this problem, if R-12 was depleting the ozone layer, it was doing so since day one. EPA went back to day one with asbestos, that cost many a company a fortune to recall products with liability suits to boot and many went bankrupt. So why not with R-12 that could kill everything on this planet like they said it could?
Got it now.
Edited: Tue July 08, 2008 at 6:47 PM by terryk
Mineral oil is for R12, however a quality ester like BVA auto 100 works just as well in my experience, and it's really all I use on conversions, and when someone wants their car "converted" back to R12. Especially if they used PAG oils to convert.
Freedoms just another word for nothing left to lose
We've updated our forums!
Click here to visit the new forum
Copyright © 2016 Arizona Mobile Air Inc.