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Brigdh posted:Thanks for this utterly unhelpful post. Due to the packaging on this car, the worst case is actually a nonfunctional car, which I'd like to avoid unexpected instances of since its my primary vehicle. You were making a much bigger problem out of something you don't have the tools to do. Once you own a vac pump, a set of gauges, and a few other select items, the job becomes a million times easier. The only time I go to a service place is to have them suck the refrigerant out, because venting that poo poo is illegal. Brigdh posted:The compressor is right next to the cooling system radiator. Unlikely, sure, but if the compressor decides to grenade, its taking out the cooling system with it. He did say worst case.... The compressor wont grenade. Stop being dramatic.
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Jun 24, 2015 19:13
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Brigdh posted:The compressor is right next to the cooling system radiator. Unlikely, sure, but if the compressor decides to grenade, its taking out the cooling system with it. He did say worst case.... Compressors grenading are very, very uncommon. And usually it's just one silly little compressor conrod saying peekaboo through the side of the housing. At which point you unplug the clutch wire (not like it matters, since neither pressure switch will ever turn on and therefore the clutch will never be energized) and continue driving.
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Jun 24, 2015 20:02
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So I determined using a leak sniffer that the slow leak in my AC system is exclusively the high-side Schrader valve on my Subaru. The low side reports a pressure of about 1 with everything off (the needle moved when I hooked it up, so I know that the gauge is working). The compressor (of course) does not cycle because the low-pressure safety switch is tripped. Is it likely that the valve just needs tightening prior to a recharge with dye and PAG-100 oil? If so, how much should I tighten it so that I don't ream the rear end in a top hat out of the aluminum fitting? From the looks of it, it appears to need like low in-lb of torque before it strips something. Seat Safety Switch fucked around with this message at 05:47 on Jun 30, 2015 |
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Jun 30, 2015 05:41
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If it is loose, tighten it as you would a screw. It bottoms out when it's fully tightened to the correct depth. Hopefully it's just that and not the valve itself gone bad. Do make sure the system still has positive pressure before you attempt a recharge (poke the schrader with a screwdriver or something), if so there shouldn't be any moisture inside and you'll probably be fine. If it is
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Jun 30, 2015 05:47
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There is actually pressure; it hissed at me when I hit the Schrader while trying to remove the leak tester from the valve holder. Not having to vac is a big plus. The valve is pretty low down in the holder so I think I'll probably have to get a valve core tool for a tire or something to tighten it down.
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Jun 30, 2015 05:48
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I've read the OP/first few pages and watched the video, and now I'm trying to learn how to fix my own AC problems, here's where I'm at: I hooked up the r-134a manifold gauges to my truck (1995 ford f150 4.9 i6). The static pressure was zero on both sides. The valves were closed and although I did crank them shut more tightly once I saw the reading on the gauges, I really don't think the valves were open or anything. When I run the truck with the AC on full I don't hear the compressor turn on. I guessed I had a huge leak somewhere that had let all the pressure out so I used a can of refrigerant with dye and eased the low side valve open. The low side pressure would increase to about 50-70 with no change on the high side and the low side pressure would slowly sink back down to zero. From reading the OP this means I need to repair my AC system rather than recharge it (I bought the truck about 6 months ago and I sort of recall the AC working then buuuuut that was near winter time and I'm probably just dumb and thought fan + ambient temperature = AC!!). I'm just wondering what I should do next. Should I wait for it to be dark and then use my uv flashlight to look for the dye? Should I replace the compressor since I never ever heard it turn on (maybe start with the fuse and also check to make sure it's getting power?). And if I do replace the compressor I should also change the dryer right? Also, I don't think I was using the gauges wrong, but right after the truck I tried to get a static reading on a 1992 camry (the AC doesn't work in it either) and also had zero pressure. Am I making some dumb mistake? I took two pictures, one of the low side gauge in the truck showing some pressure while I was adding refrigerant form the fill line and one of the camry with the AC on and the gauge showing no pressure on either side. If any pictures or videos of what I'm doing or what equipment I'm using would help, just let me know. I'm not really discouraged yet, it's fun and I'm excited to try something else next. The good news is that nobody in my family has working AC so I've got lots of opportunities to practice! Jack B Nimble fucked around with this message at 03:34 on Jul 5, 2015 |
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Jul 5, 2015 03:30
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If there's nothing on the high side stop what your doing and you need to check for obstructions. Edit: rereading your post did you hear any hissing with the engine off? A leak that big would be very noticeable.
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Jul 5, 2015 03:32
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BrokenKnucklez posted:If there's nothing on the high side stop what your doing and you need to check for obstructions. Once I decided I had a big leak and this wasn't working I closed the valve on the tap but left the valve on the low side a bit open so as to get all the refrigerant out of the gauges, meaning I left the truck running for a while and probably couldn't have heard any hissing. I didn't use all of the can with dye though so tomorrow I can add some more dye to the line with the engine off and see if I hear anything. Does the truck/AC need to be running to pull the refrigerant out of the fill line or will that just happen from vacuum? Also, from reading the OP I don't think it covered clearing obstructions, I only recall that pressure beyond the indicated level for the current ambient temperature indicated a blockage. My good buddy Scotty Kilmer says to get a heat gun and see where in the system stops getting cold, starting with the condensor as the likeliest place to break. Edit - Also do I need to get some plumbers tape for the various fittings on the manifold gauge? Jack B Nimble fucked around with this message at 03:48 on Jul 5, 2015 |
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Jul 5, 2015 03:41
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Well with out being there to diagnose anything... If it was sucking in refrigerant on the low side and nothing on the high side it would indicate a massive leak or an obstruction, most likely at the tvx/cap tube. The car does need to be running and the compressor needs to be turning to build pressure. Just guessing you have a leak in the condenser is my best guess. With dye in the system though you can at least start looking for leaks.
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Jul 5, 2015 03:49
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Jack B Nimble posted:The low side pressure would increase to about 50-70 with no change on the high side and the low side pressure would slowly sink back down to zero. Pretty much. Sounds like you're doing everything right and you have a massive leak somewhere. If you don't see it in the engine compartment look in the air box under the dash (should be able to pull the blower fan or something to get access) and look for dye in there.
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Jul 5, 2015 06:32
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Motronic posted:Pretty much. Sounds like you're doing everything right and you have a massive leak somewhere. If you don't see it in the engine compartment look in the air box under the dash (should be able to pull the blower fan or something to get access) and look for dye in there. I'm not sure how the setup is on OPs car, but I found a massive leak in my front evaporator core after I ran a can of refrigerant w/ dye through it and found the dye dripping out of a vent underneath the truck. I would check around for obvious things like that before removing parts.
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Jul 5, 2015 06:59
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Also: the dye is visible to the naked eye, but fluoresces under UV light. Most parts stores that sell refrigerant should also sell a UV pen light and UV-filtering goggles (so you don't sunburn your retinas). Makes it a lot easier to look for.
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Jul 5, 2015 07:55
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Enourmo posted:Also: the dye is visible to the naked eye, but fluoresces under UV light. Most parts stores that sell refrigerant should also sell a UV pen light and UV-filtering goggles (so you don't sunburn your retinas). Makes it a lot easier to look for. I didn't see any dye anywhere at all in the engine bay. I did see some dye/something that flouresced under the dash but it was on an electrical connector so it's either irrelevant or some sort of collateral from wherever the leak is. I haven't taken the dash apart yet because I'm not sure how to find my evaporator. In fact, I can't even really tell where the AC lines pass through the fire wall into the cabin. I believe it must be right next to the drier which itself is kind of wrapped up in some sort of covering. In this truck the heater core is actually accessed just through the glove box rather than having to take the dash off so I'm hoping the evaporator is similarly simple. At this point my goal is to just find and identify all 5 major components of the A/C. Obviously I can see the compressor, condensor, and drier but I'll need to find the evaporator and expansion valve if I want to finish looking for the leak. I have a Haynes manual for the truck but the AC section pretty much says "here's how to charge `er up, otherwise go to a shop!". Edit - it was pouring rain here Sunday, but I'll keep looking for the leak when the weather improves.
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Jul 6, 2015 01:41
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It looks like that truck has an accumulator setup. The accumulator (the upright black cylinder, what you called the drier) should have a line coming off the side or back that goes directly into a black plastic case on the firewall; that's the evaporator case. Depending on stuff in the way you should be able to take that case apart to access the evaporator from the engine bay, or you might be able to just shine a light in to see if there's dye or not. That setup also uses a fixed orifice instead of an expansion valve; the orifice tube is inside the other pipe coming out of the box, should have an insulated line going into it at a fixed angle.
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Jul 6, 2015 02:32
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Just fixed the AC in my boring DD forester with advise from the OP. Thanks dude, beer's on me at NEAI. First time I've ever had AC that lasted more than a few hours before leaking out again, and I am ruined. I don't think I can drive cars without AC anymore. This is amazing, why did you guys not tell me? Next we might get flush toilets and hot water here.
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Jul 6, 2015 02:56
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Let's talk flushing. My AC compressor clutch is finally shot and I'm going to be replacing the compressor shortly once I can get the car in for refrigerant recovery. The compressor itself is old and worn out but is still mostly working and probably hasn't spat its innards through the system. I'm also going to be replacing the condenser and drier at the same time. The expansion valve was replaced last fall so I probably won't touch it since it's kind of a hassle to get out from under the dash. I've got one of those compressed air powered flushing tools and a gallon of A/C flush ready to go, my plan was to flush all the lines in the engine compartment and based on how much gross stuff comes out remove and flush the under dash components. It occurred to me that my source of compressed air is a regular compressor and 15 minutes of air pushing out the flush chemical might introduce compressor oil and water into the system. I've got a tank of Argon or a tank of CO2 I can adapt to blow out the flush, or I can go buy some line driers for my compressor if necessary. What's really needed here? Is this worrying about nothing? My compressor is an oiled 5 gallon nailer type with 50 or 100 feet of air hose sucking in low humidity air. I've got a couple cans of R134a ready for this but the duster conversion is interesting. Have you noticed if a duster converted system designed for R134a puts less of a load on the engine than the same system equipped with R134a? Is it possible to source non-bitterant cans of duster or do you just use the ones with bitterant and not worry about it? Finally, how do you go about disposing of it if you need to service the system in the future? The nice thing about R134 is you can go into any shop and have them empty it for you.
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Jul 6, 2015 02:59
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Hit up a hardware store and buy one of these. http://www.harborfreight.com/38-desiccant-dryer-with-oil-removal-filter-69923.html and if you really want to get one of these too http://www.harborfreight.com/inline-desiccant-dryerfilter-68215.html those will remove 99% of the moisture, other wise, the argon/co2 thing would work just fine too.
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Jul 6, 2015 03:41
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Bruinator posted:It occurred to me that my source of compressed air is a regular compressor and 15 minutes of air pushing out the flush chemical might introduce compressor oil and water into the system. I've got a tank of Argon or a tank of CO2 I can adapt to blow out the flush, or I can go buy some line driers for my compressor if necessary. What's really needed here? Is this worrying about nothing? My compressor is an oiled 5 gallon nailer type with 50 or 100 feet of air hose sucking in low humidity air. Compressor oil is bad, but you should already be running a dryer on lines for poo poo like this. Or all lines unless you're running an oiling system for tools. If you aren't but your compressor isn't a disaster I wouldn't worry about it. And by disaster I mean you have have to top it up with oil all the time. Bruinator posted:I've got a couple cans of R134a ready for this but the duster conversion is interesting. Have you noticed if a duster converted system designed for R134a puts less of a load on the engine than the same system equipped with R134a? I cant say I have, but based on how loving cold it is in an R134a system I suppose it just might do that to some degree depending on your desired set temp. Bruinator posted:Is it possible to source non-bitterant cans of duster or do you just use the ones with bitterant and not worry about it? I'm sure it is.....but I never have. The only time the bittereant caused me problems was in that loving OP video where I hosed up puncturing the can and shortly thereafter put a dip in (yes, I washed my hands first....no it wasn't enough). Bruinator posted:Finally, how do you go about disposing of it if you need to service the system in the future? If you don't have a recovery pump and dedicated tank for it you're pretty much on your own. I'll leave it at that.
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Jul 6, 2015 06:49
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Motronic posted:If you don't have a recovery pump and dedicated tank for it you're pretty much on your own. I'll leave it at that. I love how the second you put it into an A/C system, you aren't allowed to do what it was sold to do - vent it to atmosphere.
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Jul 6, 2015 14:48
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To be fair, that rule was invented for stuff that's actually really bad, like R-12 and R-22. It only got applied to 134a because it falls under the category of "Refrigerant". The same rules apply to R-744 (carbon dioxide, which you are venting as you read this), R-50 (methane), R-717 (Ammonia, but for good reason, that poo poo is toxic), and all the other magickal replacement blends that are non ozone-depleting.
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Jul 6, 2015 15:05
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I can get duster cans of R134a that don't seem to have bitterant in them. Would you be able to smell it in normal use?
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Jul 6, 2015 15:51
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So I was at Canadian Tire looking for straight R134 and came across some Red-Tek "R12A" stuff that claims to be a replacement for R134a and "R12 substitutes." In teeny tiny little print further down on the can it says you have to totally evacuate any existing refrigerant because it is totally incompatible with existing R134a in the system, and you have to put a little sticker next to the low side valve to warn the next guy that you have replaced the refrigerant. The shelves were almost bare.  Surprised that they feel like they can just sell this stuff when 99.999% of people buying it are just going to grenade their cars with it.
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Jul 6, 2015 15:55
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Seat Safety Switch posted:Surprised that they feel like they can just sell this stuff when 99.999% of people buying it are just going to grenade their cars with it. Hey boss, we've got this stuff left over from our lng extractions that we can't really sell as propane or other stuff already in industrial use. Should we burn it off? No, I've got a perfect idea. Have our layers and marketing guys get in touch with the "nutritional supplement" folks, we can use their best practices to sell this crap to suckers in busted up old cars
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Jul 6, 2015 19:15
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Motronic posted:stuff Thanks. My air compressor consumes very little oil and drains practically no water from the tank this time of year but you're right, it's probably time to upgrade my system with a drier. I don't paint or blast or plasma cut since my compressor isn't that big and manually oil my tools before use so no oiler either. Being able to vent a "safe" refrigerant like 152a, those eco friendly 134a substitutes, etc would be a major advantage. I've tossed around the idea of buying a recovery pump and tank but at my rate of usage it hasn't justified itself yet. Short of some sort of DIY contraption the cheapest recovery machines I've seen go for about $400 (Robinair RG3) plus $100 for an empty tank.
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Jul 6, 2015 20:37
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So ive just got back to loving with the civic. http://s639.photobucket.com/user/RonJ_HT/media/picture_4656.jpg.html The above is the wiring diagram. My condenser fan cycles. My static pressures are right for the temperature. My operating pressures at start with outside temp of 90 are 45psi/225psi, after running in park for a while, the pressure are more around 30/220. It seems to stay cold for quite a while if I leave it parked. When I try to drive it how ever, after a few miles the compressor shuts off and the AC blows hot. My reading of the wiring diagram is that the two options are a bad relay, or a bad compressor clutch. Any other ideas?
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Jul 6, 2015 22:18
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Start at the clutch. If there is power there, you know which is bad. Though it all depends on the system, you might have a pressure sensor too.
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Jul 7, 2015 00:16
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I have good power at the clutch and as far as I can tell all the sensors are before the relay for the clutch. I guess only possibility other than a bad clutch is a bad ground but I think it's grounded through the motor.
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Jul 8, 2015 14:03
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I'm gonna blow my brains out over this poo poo heap explorer's AC. Replaced high side line, compressor, condenser, accumulator, o tube, and full system flush. Mechanic insisted pressures are fine even though I showed then the OP and saw pressures at least 75 psi low, and that the system only turns on in cooler temps. One it's over a hundred, it stops even engaging. To make matters worse is it's a retrofit.
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Jul 8, 2015 16:43
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Sadi posted:I have good power at the clutch and as far as I can tell all the sensors are before the relay for the clutch. I guess only possibility other than a bad clutch is a bad ground but I think it's grounded through the motor. Sounds like a bad clutch. Now, this is a very dangerous thing, but turn on the ac, and very very gently tap the clutch with a wood handle of a hammer or the end of the a screw driver. If the clutch engages, then the air gap needs to be adjusted. If not then yeah, the clutch is toast. Just be very careful as there is lots of poo poo flying around and you don't want to get injured doing that. most clutches are grounded through the motor, so if your engine is running, more than likely its grounded correctly.
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Jul 8, 2015 17:49
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So now the mechanic has said if it stops operating, just let out a little refrigerant.... That can't be shorthand for "we couldn't be assed to balance the system properly," could it?
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Jul 8, 2015 19:49
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Trip report on the Robinair 18340 valve core set.  Swapped the high and low side valve cores on a Mazda3 today. High side was definitely leaking, and low had some pressure under the cap when I was checking things over. After debating the Mastercool kits, I picked up this one on Amazon, mostly because I also got an inquiry on a GM vehicle where I'd need the GM valve tool. Worked great, other than the cutoff valve needing more force than I expected to close. Once you've turned it and you think it's seated, give it some more force and make sure. I had another turn or two past what I thought felt like "closed", it just required quite a bit more force. A+ would buy again. At this point, the only thing I really need is an evac machine and cylinder in order to do just about everything AC related. Wasabi the J posted:So now the mechanic has said if it stops operating, just let out a little refrigerant.... Sounds if you're seeing pressures that are too low, either they don't have it charged to the proper refrigerant volume/weight, or your compressor is poo poo. And wtf, "let some out"? I'm assuming these guys don't specialize in AC, or they're idiots. Do you have gauges? If you do, or have access to them, I'd start by following the directions in the OP. Shoot a can of dyed refrigerant in if the pressures are low, and search around with a UV light in a week if you can get the pressures right. PitViper fucked around with this message at 23:02 on Jul 8, 2015 |
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Jul 8, 2015 22:58
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PitViper posted:Trip report on the Robinair 18340 valve core set. Nice, I've got the cheaper Mastercool valve core kit 58531 since it came with the JRA core tool and was able to replace my cores with the system charged with no issues. Also recommended if you don't need all the core adapters in the Robinair set.
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Jul 9, 2015 05:22
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Wasabi the J posted:So now the mechanic has said if it stops operating, just let out a little refrigerant.... It's shorthand for "find a mechanic that actually knows AC."
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Jul 9, 2015 05:32
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We've got a Lexus SC430 with non functioning AC. Static pressures are right, but low/high side running pressures are about 90 and 170 psi respectively with A/C on. That's probably a bad compressor, right? It's also had periodic issues with vent doors switching uncommanded, and according to my mom it sometimes gets an odd smell coming from the vents after about 30 minutes running, but I've never noticed it myself so I couldn't say if it's coolant or not; with all this we might take it to an A/C specialist regardless, I don't feel like fiddling with electronic HVAC controls for the vent issue.
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Jul 9, 2015 05:42
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Enourmo posted:We've got a Lexus SC430 with non functioning AC. Static pressures are right, but low/high side running pressures are about 90 and 170 psi respectively with A/C on. That's probably a bad compressor, right? Re-read the OP. A correct static pressure means nothing other than you have some amount of liquid refrigerant left in the system. The static pressure of any amount of liquid refrigerant in a closed system is the same (at a given temperature) if it's a thimbleful or a tanker truck full in absolutely any sized container no matter how large or small. This is basic physics.
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Jul 9, 2015 06:14
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Yeah but it seems like if it's just low refrigerant, it would still draw the low side down to ~30 psi and just the high pressure side would be too low, wouldn't it? I know about the equilibrium pressure. Once I get a chance to look at the car again (it's currently being lent to a family friend) I'll take another look, I've got some spare refrigerant from charging my car so I may toss that in and see if things improve.
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Jul 9, 2015 06:27
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t depends on what is happening on the gauges and with the compressor clutch when this is going on. Are you saying they are just staying at those pressures? If so and even if the clutch is engaging, it could be slipping. You can't just say it's a compressor without doing a bit more diagnosis. If the gauges are moving exactly how in relation to each other is pretty important, and I'm pretty sure that car has a TXV so that could still be an issue (if it's not closing properly). Honestly there are the situations where I like to go down to the shop and recover the system so I can put a correct measured charge weight into it in order to remove at least one variable.
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Jul 9, 2015 06:37
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They were pretty steady from what i recall, but like i said I'll check again next time. It could be the expansion valve now I think of it; the failure seemed pretty abrupt. Then again the last I know the a/c worked was last July; it had been on long-term loan from roughly September to this past May, and the guy who had it for most of that is the type not to care about a/c so he may have just never used it. Anyway, i'll quit making GBS threads up the thread with my baseless speculation.
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Jul 9, 2015 06:44
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Hey guys, actually read the OP and got myself a real AC manifold gauge. Civic Si, 2007. Intermittent compressor turning off...seems to be a "overheating" type of issue (not neccesarily heat related, but let me explain). Depending on how hot the day is, AC runs for 10-20 minutes (relatively cold, but not ice cubes) and then the compressor turns off. If the day is cooler, it will run longer before turning the compressor off. If I leave it off for about 10 minutes then turn it back on, it blows cold again, for about 10 minutes or maybe less. I swapped some relays, they seem good. All the fans turn on when they are supposed to. I hooked up my gauges and it seemed low yesterday. Put a full can of regular R134 into it. Blew much colder, but on a longish road-trip, the AC stopped working after about 25 minutes or so. If I waited 5 minutes, it would work again, running for another 5-10 minutes before the compressor turned off again. I pulled out my gauges today, and the readings are this, with the AC turned on max/recirc/etc: Ambient: 75 F Low: ~35 High: ~150 Based on the chart in the OP, this seems low, but I am very worried about overfilling it. I cant seem to find anything online that shows the proper pressures for this system. Should I grab another can and top the system off? Any other ideas regarding my problem? Failing compressor or clutch? Some sort of temperature sensor on the fritz, or the HVAC control unit being fucky? The car does not show overheating at all, on the dash gauge or on an OBD2 reader.
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Jul 11, 2015 15:41
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Pressures for R134a systems are the same across the board, that's just physics. Use the chart in the OP for reference, it will work for any R134a system. Can you get a pressure reading when it's refusing to operate? I'd take a wild guess that your evaporator is freezing, which could be from being dirty or not having much airflow due to a dirty cabin air filter, or just undercharged refrigerant. Get the pressure readings from when it fails before you add any more refrigerant.
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Jul 11, 2015 20:02
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