No cool
07-06-2016, 03:30 PM
#1
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Thread Starter
Join Date: Nov 2012
Location: Fl, USA
Posts: 249
No cool
We've been having some heat index of over 100 deg here in Florida and it broke my ac. It sounds like I have broken valves in the compressor. I am wondering if I should go with a junkyard unit or new/reman. I have to decide by this wkend because there is no driving this car in this kind of heat here in Florida.
07-07-2016, 06:21 AM
#2
The heat wouldn't break your compressor - but regardless, these compressors are inordinately reliable. I'd have no qualms about slapping on a JY unit. Of course you want to make sure it doesn't look totally trashed and ideally find one from a system that still has its charge (i.e., briefly depress a Schrader valve and make sure some refrigerant hisses out).
Although if your compressor truly has suffered mechanical failure it's very possible you've now polluted the entire system. Before slapping on a new compressor you want to make sure that is not the case. Make sure you have no "black death" in the lines, no metal shavings, everything looks clean, good clean oil, etc.
Although if your compressor truly has suffered mechanical failure it's very possible you've now polluted the entire system. Before slapping on a new compressor you want to make sure that is not the case. Make sure you have no "black death" in the lines, no metal shavings, everything looks clean, good clean oil, etc.
07-07-2016, 09:28 AM
#4
The 3rd gen actually takes to r134 conversions very well. And I'm even talking about the inferior method of just switching the service ports, throwing some ester oil in it, and then the r134. Works much, much, much better than conversions on other makes/models.
But anyway, I would still prefer to stay R12 in your situation. R12 is still really plentiful contrary to popular opinion. While individual charging cans are less than ideal for a perfect charge (by weight), they are very plentiful all over CL and eBay for about $20 a can. If you're worried about it, just scoop some up now while you're thinking about it.
It takes about 32 oz total refrigerant in the system, so three 12 oz cans will put you pretty much right on. I say that because rule of thumb is that you "lose" 2 oz of refrigerant in your manifold gauge set, plus 1 oz of refrigerant leftover in each can. So three 12 oz cans should mean about 31 oz actually making it into the system which should put you right on the money. So three cans - about $60 - that's all it takes for you to quell your R12 worries.
I have a bunch of individual R12 cans, but I also have a 50 lb drum of R12 and prefer to work from that because I can dial in the exact charge (by weight) with my refrigerant scale. Can't do that with the little individual cans. My only car now that has R12 is my Civic and I actually reverted BACK to R12 after an incredibly poorly performing proper R134 conversion a few years back.
But anyway, I would still prefer to stay R12 in your situation. R12 is still really plentiful contrary to popular opinion. While individual charging cans are less than ideal for a perfect charge (by weight), they are very plentiful all over CL and eBay for about $20 a can. If you're worried about it, just scoop some up now while you're thinking about it.
It takes about 32 oz total refrigerant in the system, so three 12 oz cans will put you pretty much right on. I say that because rule of thumb is that you "lose" 2 oz of refrigerant in your manifold gauge set, plus 1 oz of refrigerant leftover in each can. So three 12 oz cans should mean about 31 oz actually making it into the system which should put you right on the money. So three cans - about $60 - that's all it takes for you to quell your R12 worries.
I have a bunch of individual R12 cans, but I also have a 50 lb drum of R12 and prefer to work from that because I can dial in the exact charge (by weight) with my refrigerant scale. Can't do that with the little individual cans. My only car now that has R12 is my Civic and I actually reverted BACK to R12 after an incredibly poorly performing proper R134 conversion a few years back.
07-07-2016, 10:16 AM
#5
The 3rd gen actually takes to r134 conversions very well. And I'm even talking about the inferior method of just switching the service ports, throwing some ester oil in it, and then the r134. Works much, much, much better than conversions on other makes/models.
But anyway, I would still prefer to stay R12 in your situation. R12 is still really plentiful contrary to popular opinion. While individual charging cans are less than ideal for a perfect charge (by weight), they are very plentiful all over CL and eBay for about $20 a can. If you're worried about it, just scoop some up now while you're thinking about it.
It takes about 32 oz total refrigerant in the system, so three 12 oz cans will put you pretty much right on. I say that because rule of thumb is that you "lose" 2 oz of refrigerant in your manifold gauge set, plus 1 oz of refrigerant leftover in each can. So three 12 oz cans should mean about 31 oz actually making it into the system which should put you right on the money. So three cans - about $60 - that's all it takes for you to quell your R12 worries.
I have a bunch of individual R12 cans, but I also have a 50 lb drum of R12 and prefer to work from that because I can dial in the exact charge (by weight) with my refrigerant scale. Can't do that with the little individual cans. My only car now that has R12 is my Civic and I actually reverted BACK to R12 after an incredibly poorly performing proper R134 conversion a few years back.
But anyway, I would still prefer to stay R12 in your situation. R12 is still really plentiful contrary to popular opinion. While individual charging cans are less than ideal for a perfect charge (by weight), they are very plentiful all over CL and eBay for about $20 a can. If you're worried about it, just scoop some up now while you're thinking about it.
It takes about 32 oz total refrigerant in the system, so three 12 oz cans will put you pretty much right on. I say that because rule of thumb is that you "lose" 2 oz of refrigerant in your manifold gauge set, plus 1 oz of refrigerant leftover in each can. So three 12 oz cans should mean about 31 oz actually making it into the system which should put you right on the money. So three cans - about $60 - that's all it takes for you to quell your R12 worries.
I have a bunch of individual R12 cans, but I also have a 50 lb drum of R12 and prefer to work from that because I can dial in the exact charge (by weight) with my refrigerant scale. Can't do that with the little individual cans. My only car now that has R12 is my Civic and I actually reverted BACK to R12 after an incredibly poorly performing proper R134 conversion a few years back.
07-07-2016, 11:43 AM
#6
i still have cans of R12 around along with lines and gauges. my only concern is when i have to buy components. dont they pre fill the compressor with R134a oil? do i have to flush out the entire system? i'm staying with R12 as long as i can but my fear is that component failures will make me switch over to R134a which IMO was krap compared to the cooling of R12.
That's why, as a personal rule, I always drain brand new compressors entirely and that is for a few reasons. Often times you don't know exactly WHAT is in there. Is it PAG? If so, what kind? Is it ester oil? Is it assembly lube? Is it some sort of arbitrary additive like that Ice 32 stuff? You never really know, and even though the compressor SHOULD be labeled with what's in it and how much, you still don't want to rely on that and take their word for it. I've had compressors say they come pre-filled with X amount of Y and in reality it's dry.
So anyway, drain the new compressor entirely, always. That way you start with a clean slate. What I do is just turn the compressor upside down and set it on top of an old pot or pan and let it drain out of the suction/discharge ports over the course of several hours. If you occasionally turn the clutch by hand you'll work some more out too. You won't get it bone dry, but the residual amounts left over will be negligible. That way you can start fresh yourself with your oil of choice and the exact amount required.
Let's say you need a new suction or discharge hose at some point, that's still a non-issue. If they are new construction, yes, they will have the new style barrier (R134) hose but that's irrelevant because the R134 components like hoses/o-rings/etc. are all backwards compatible with R12. R12 can't leak through the modern HNBR green seals/o-rings or barrier hose, but in the opposite scenario, R134 can and does leak through the old material brown and black seals/o-rings found on R12 systems as well as the old style non-barrier hose (because the R134 molecules are smaller than R12 molecules).
07-07-2016, 04:07 PM
#8
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Thread Starter
Join Date: Nov 2012
Location: Fl, USA
Posts: 249
Thanks guys, I will head to the jy this weekend and hope there is a max there worthy to donate its compressor. I don't believe the system is contaminated but to be safe, I will blow it out with dry nitrogen.
I too always charge by weight; it takes the guess work out. I will give an update when it's done.
I too always charge by weight; it takes the guess work out. I will give an update when it's done.
07-07-2016, 07:45 PM
#9
I converted to r134a after having to replace a condensor and James is right it took the conversion well. The only change made was the service port on the low pressure side and the ac has been ice cold for about the past 6yrs with no issues so so far so good. Nitrogen is good for pressure testing the system but it should be hooked up to a vacume pump before recharging the system to be safe. Atleast thats what i've been told by hvac tech's in the past is that as a rule of thumb once the system has been opened or exposed to air it should be hooked up to a vacume pump before charging to be safe. I believe only 93-94 had r134a and 89-92 was r12. r12 is harder to come by here and i might be wrong but i think it can't be used here anymore in Ont.
07-08-2016, 06:33 AM
#10
I converted to r134a after having to replace a condensor and James is right it took the conversion well. The only change made was the service port on the low pressure side and the ac has been ice cold for about the past 6yrs with no issues so so far so good. Nitrogen is good for pressure testing the system but it should be hooked up to a vacume pump before recharging the system to be safe. Atleast thats what i've been told by hvac tech's in the past is that as a rule of thumb once the system has been opened or exposed to air it should be hooked up to a vacume pump before charging to be safe. I believe only 93-94 had r134a and 89-92 was r12. r12 is harder to come by here and i might be wrong but i think it can't be used here anymore in Ont.
i still like R12...the performance is great compared to R134a. it's just colder.
07-08-2016, 07:20 AM
#11
Personally, I vacuum my vehicles for at least an hour and then I let them sit overnight to make sure the vacuum holds overnight. Of course in a shop where they need to get cars in and out quickly they don't have time to do that, so they normally only let it sit for half an hour or so. A rather large leak will show up in that time but a smallish leak isn't going to show up only watching it half an hour or so (i.e., the type that will mysteriously make you low on charge every few months).
Ensuring that it holds vacuum for hours or even ideally a full day or so is a much better indicator of being long term leak-free IMO. But that's one of the benefits you have when you do it yourself and aren't time-constrained like a shop.
BTW ac - it's not just "to be safe" to vacuum a system prior to charging, it's absolutely a must IMO and I would assume any competent shop should have that same mentality
. I'd be pretty mad if some shop opened my system and did not vacuum it prior to recharge because you just simply aren't going to get the best performance (i.e., vent temps) with a system that's full of moisture.
Ensuring that it holds vacuum for hours or even ideally a full day or so is a much better indicator of being long term leak-free IMO. But that's one of the benefits you have when you do it yourself and aren't time-constrained like a shop.
BTW ac - it's not just "to be safe" to vacuum a system prior to charging, it's absolutely a must IMO and I would assume any competent shop should have that same mentality
. I'd be pretty mad if some shop opened my system and did not vacuum it prior to recharge because you just simply aren't going to get the best performance (i.e., vent temps) with a system that's full of moisture.
07-08-2016, 07:43 AM
#12
Personally, I vacuum my vehicles for at least an hour and then I let them sit overnight to make sure the vacuum holds overnight. Of course in a shop where they need to get cars in and out quickly they don't have time to do that, so they normally only let it sit for half an hour or so. A rather large leak will show up in that time but a smallish leak isn't going to show up only watching it half an hour or so (i.e., the type that will mysteriously make you low on charge every few months).
Ensuring that it holds vacuum for hours or even ideally a full day or so is a much better indicator of being long term leak-free IMO. But that's one of the benefits you have when you do it yourself and aren't time-constrained like a shop.
BTW ac - it's not just "to be safe" to vacuum a system prior to charging, it's absolutely a must IMO and I would assume any competent shop should have that same mentality. I'd be pretty mad if some shop opened my system and did not vacuum it prior to recharge because you just simply aren't going to get the best performance (i.e., vent temps) with a system that's full of moisture.
Ensuring that it holds vacuum for hours or even ideally a full day or so is a much better indicator of being long term leak-free IMO. But that's one of the benefits you have when you do it yourself and aren't time-constrained like a shop.
BTW ac - it's not just "to be safe" to vacuum a system prior to charging, it's absolutely a must IMO and I would assume any competent shop should have that same mentality
. I'd be pretty mad if some shop opened my system and did not vacuum it prior to recharge because you just simply aren't going to get the best performance (i.e., vent temps) with a system that's full of moisture.
07-08-2016, 01:37 PM
#13
I guess technically I don't do a full day. What I try to do is vacuum it down in the evening, then let it sit overnight and - assuming it hasn't lost vacuum - I then charge it in the morning. So technically I guess it's 10-12 hours rather than a full day, but still much more ideal than 20-30 minutes.
07-10-2016, 05:13 AM
#14
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Join Date: Nov 2012
Location: Fl, USA
Posts: 249
Ac, Nissan went to R134a towards the second half of 92. My car is a 94 so already 134a. You're all correct about the processes of recharging the system and the importance of pulling a vacuum. Moisture is the enemy. It not only causes blockage but it also makes the system acidic which ruins the windings and internal components. I go a step further in using a micron gauge when I vacuum and unless I am below 500 micron, the system does not get charged.
I am hoping to get to the treasure yard today to look for a compressor.
I am hoping to get to the treasure yard today to look for a compressor.
07-26-2016, 05:49 PM
#15
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Join Date: Nov 2012
Location: Fl, USA
Posts: 249
So, I concluded a little too quickly my compressor was defective without gauging up to the system to see what was going on. I finally got a chance to replace the compressor today and after completing the process the system immediately pumped down into a vacuum on the low side which indicats a restricted expansion valve so, now the laborious task of replacing valve has to begin.
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