Engine Size: 1.5
Refrigerant Type: R12
Country of Origin: United States
I'm new here and I'm literally desperate for help with my Civic A/C. I'm going to give a recap of its recent history and hope one of you guys can help me out. I'm sorry this is long but please read through it as I'm trying to give the complete/accurate history for the best advice.
I have an '89 Civic hatchback that was an original r12 system. Sanden compressor. Originally, the A/C blew cold, but it blew so weak it was useless. I put in a new blower motor and new climate control unit to no avail. Eventually, I inspected the evaporator unit and noticed it was so caked with gunk (animal hair, etc. from the previous owner) that it was useless, and realized that's why it wouldn't blow hard. I bought a new evaporator and expansion valve, and keeping with popular opinion I converted to r134a.
June 08 - Since I'm a DIY'er and a bona fide "car guy" I decided to do the conversion myself. I completely took apart the whole system and flushed each line one by one, flushed the condenser, replaced the drier, replaced all o-rings, set it on a vacuum, checked that it held vacuum, etc. I charged it according to the factory service manual. Well, the car would cool decently well when driving on the highway (about 60 deg. vent temp), but at idle the darn thing blew about 95 degrees at the vent. I tried everything possible to get the conversion to work decently, and even upgraded the condenser fan to a high-output electric unit, which only minimally improved idle temps. I decided that r134a just wasn't cutting it and decided to revert to r12.
July 08 - So, I did it all over again. Took apart the whole system, replaced the expansion valve, replaced the drier, flushed every single line by hand, replaced every single o-ring, etc. My father was an ASE Master Tech and my brother and I have several boxes of r12 still, so I called around to local reputable shops and found one who agreed to use my r12 and vacuum/charge my system. Well, they charged it, got the car back that evening (it blew cold that night but I wasn't able to test it in the heat of the day at idle), and the next day it was blowing hot again. I noticed they had stuck some sort of brass adapter on the low-side fitting, and this adapter was loose and invariably explained why the charge had leaked out. I went back to them to complain, they denied all fault, etc. but agreed to recharge my system (of course, I had to give them 2 more cans of r12).
A few hours later, they call me and say the compressor is leaking, and that they'll fix it all for $1300 and do a r134a conversion. I told them fat chance and that I would come pick the car up. I went to pick the car up and since I was a bit skeptical of them I asked them to show me where the compressor was leaking, which they were never able to demonstrate to me. I then asked for my r12 cans back and they said they didn't have it because they used the r12 to introduce the UV dye into the system (I realize the dye requires some refrigerant, but not 2 full bottles). This caused quite a rage on my part and I ended up in a shouting match with the shop owner. So I left and parked the car for the rest of the month out of frustration.
August 08 - I decided to buy a rebuilt compressor and start fresh with the car. I figured with a complete "brand new" system there would be no reason the system shouldn't operate properly. I took the whole thing back apart, flushed every single line by hand, flushed the condenser and evaporator, replaced every single o-ring, and replaced the expansion valve. I bought a new drier for it and put it in place but didn't hook up the lines yet. I put 4 oz. of mineral oil in the compressor, 2 oz. in the condenser, and 2 more oz. in the lines. I then found a different reputable shop and took it to them (along with two more cans of r12) to have them vacuum and charge it (I also asked him to wait to hook up the drier lines until he had time to vacuum it). When I got the car back I noticed they had also put UV dye into the system (i.e., it was green in the sight glass on the drier). The A/C now worked "OK" but still would creep up to about 80 degrees at idle (ugh). I still wasn't completely satisfied with it but decided to live with it since summer was almost over.
Shortly thereafter, the original engine blew an oil seal. I took this as motivation to go ahead and put in my freshly rebuilt "new" engine and transmission (stock d15b2 mated with Si transmission), which I did over the winter. I didn't touch the A/C system during this and was more than careful with all the A/C lines, etc.
Fast forward to today/now - the AC has no refrigerant. It somehow completely lost its charge over the winter so I'm seemingly back at square one. The last shop did put dye into the system as I said, but the only trace of it I can find anywhere is at the rubber cap on the high side line (it doesn't fit well), so I'm guessing it could have leaked out there.
I refuse to believe that these cars came from the factory with such awful cooling ability (i.e., 80 degree vent temps at idle) and I really need to drive the car this summer. I did some searching here before I decided to post this thread and it seems the general consensus were these A/C systems are pretty anemic, but I still don't think that from the factory they cooled so awfully - otherwise there'd be none of these cars in the south. The car is virtually 100% restored down to the carpet and gets GREAT gas mileage, but without a decent A/C system it's virtually useless in the summer time.
So, at this point, I'm looking for advice. The whole system on the car is new (although admittedly I am looking for a new/replacement pressure switch but can only find r134a conversion ones, I'm also going to replace the A/C relays just for the heck of it). Does ANYBODY know a 100% fool-proof reputable shop/person I could get to help me in the Dallas, TX area? If not, does anybody have personal expert experience with the '89-91 Civic A/C system? Does anybody know of, or can provide, a fool-proof "step by step" how-to for me to do it myself? I have all the tools but virtually no experience beyond my attempt to do the original r134a conversion. I'm also about $2,000 in the hole for all this A/C trouble with nothing to show for it and I'm really just very desperate to get it all squared away
I have a '91 Civic 4-door and run R-134a in it. It works reasonably well. My climate is not as severe as yours though. In 90 degree weather, vents will be under 60 at idle, and easily reach 40 at highway speed. If you have the same parts (especially the condenser) as a '91 does you should get good performance especially with R-12. If the condenser is different and a '91 one will bolt on, it should be an improvement to go to that.
First off, there is a leak that needs to be found. An electronic detector might be a good investment here. Dye will generally only leak out while the system is running. In case of an off-season leak all the refrigerant could be gone but no traces of dye. There will always be dye on the service caps so you can't conclude one way or the other from that. With an electronic detector, you could introduce a small amount of R-134a for static leak testing. Do not run the compressor of course.
You used too much oil. Total capacity is only 5 oz starting with all parts clean and dry. This can hinder performance considerably. (the capacity chart says to use 4 oz oil in a '91, so some of the parts must be different). Speaking of clean and dry, flushing parts can introduce problems with residual flushing solvent.
When replacing a TXV, it is important to get the temperature sensor part properly attached to the evaporator outlet line. Also it must be well insulated from external heat.
Check the heater valve on the firewall. It must be closed fully with the dash control on full cold. One way to tell poor refrigeration from reheating is to feel the low side line. The air at the vents should be approximately as cold as the line gets. Both radiator/condenser fans should run at the same time, whether they come on with the A/C or because of engine heat. If you ever see only one fan running, there is a problem with the other one.
Thanks for your reply. I'm not sure if the '91 sedan uses the same compressor or not. Mine uses the Sanden, but a buddy of mine has a '90 Si hatchback and his uses the Mastuba (sp) version.
As far as the oil, I actually went to AirPro (their warehouse/shop is close to me) and followed their directions with the 4 oz. in the compressor, 2 oz. in the condenser, 2 oz. in the lines thing. I think I actually consulted another A/C forum (it wasn't this one but I can't find it now) and got similar suggestions from those guys. If I "start all over", what should I do about this? I assume some residual oil stays in the condenser, etc. and is hard to get out even with flushing.
I'm certain the expansion valve is properly attached. I also insulated it fully with the rubbery tape (I feel like a doofus but I can't recall what it's called).
I never checked the heater valve on the firewall, and I can't quite remember how cold the low side line ever got.
First thing would be to find the leak. When you're using R-12, staying free of leaks is a top priority. Depending on what is leaking that could force you into what to do next.
First locate the leak....#1 priority. Suggest to replace the schrader valves in both fittings (great source for leakage). Suggest to remove all components and re-flush the system. The lubricant charge stated is excessive....OE is 5 oz. Insure that the TXV sensor bulb is mechanically attached to the evap outlet...failure to accomplish this will result in severe cooling loss. Insulate the bulb..not the valve. Insure that there are no leaks in the evap. If the evap has been changed...insure that the evap is the OE type...should be constructed of aluminum and is serpentine flow pattern. Some aftermarket units (brass and copper) do not cool as well as the OE type.
A major problem with this repair is that the correct amount of refrigerant was not installed in the system. 2 cans=24 oz. System recharge is 31 oz. This is a serious undercharge and the system will not cool under these conditions ( Excessive lube and undercharged refrigerant). Also realize that when adding refrigerant into the system using cans and gauges, the first four ounces is required to pre fill a standard set of gauges. Combine this to the possibility of Lapp 1 oz remaining in each can and there is a serious possibility of a undercharge.
Also insure that condenser cooling fan is operating correctly.
The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
I wouldn't change anything without confirming that it leaks first.
Some cars have special valves, but the standard generic shrader valves will fit your car. They look exactly like tire valves but they have a different sealing rubber material (so do NOT try to use tire valves).
It is possible to make these cars cool well. This pic was taken at idle. Ambient was around 90 degrees, but the car was in the shade. It was a 1990 DX that I bought from a friend as a fixer/commuter. System was an ALL original dealer-installed system (I think all DXs were dealer-installed then) and it had not been used for about 8 years and never had been serviced. I added enough R12 to clear the sight glass and leak checked the system. I too had a small leak at the high-side schraeder when the cap was off.
Good luck with your project. These guys have given you good advice
My personal opinion you would be wasting $70.00 dollars if you purchased that leak detector. These systems cool well both OEM and aftermarket.
To check for leaks with an electronic detector, add enough R-134a to get 50 or 75 psi. You can then add nitrogen to increase the pressure but do not exceed 150 psi or so, as that is all that a typical evaporator can handle. Do not engage the compressor. Use R-134a do not waste R-12 on this. It is actually legal to just vent the R-134a out after the test because it was used as a leak checking agent, not a refrigerant.
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