Getting A/C going for first time on 5.3l - The 1947 - Present Chevrolet & GMC Truck Message Board Network

chevyman70 · 04-24-2013, 09:59 PM

Okay, I am starting to get my AC parts together for my 5.3l swap. I know I need freon 134r and PAG oil (which weight?). I am using the nippodenso compressor. What do I first? Where do I add the oil, and how much freon do I need?

**Clyde65** · 04-25-2013, 08:20 AM

Its cheap enough to take what you have to a shop that specializes in AC work, have them charge it. Also did you use a trinary switch or binary? I suggest a trinary so you can protect your AC system and run electric fans when needed.

ChevyCruizer · 04-25-2013, 11:59 AM

What AC system, stock 70's components with new style compressor, old air, etc? That will matter for both the refrigerant capacity as well as the amount of oil.

I usually take the oil capacity and split it between the compressor and the receiver dryer/accumulator. Usually more into the compressor and cycle the compressor by hand to "work it around". Don't "work" it too much or it will squirt out of the discharge port. Also when I first start the car (after charging the system) turn the AC on and off several times. On for 3 or 4 seconds (make sure the AC clutch is engaged) then turn it off quickly for 10 seconds. Do this several times to "work" the oil through the system.

Quote:

Originally Posted by chevyman70

Okay, I am starting to get my AC parts together for my 5.3l swap. I know I need freon 134r and PAG oil (which weight?). I am using the nippodenso compressor. What do I first? Where do I add the oil, and how much freon do I need?

chevyman70 · 04-25-2013, 02:41 PM

Quote:

Originally Posted by Clyde65

Its cheap enough to take what you have to a shop that specializes in AC work, have them charge it. Also did you use a trinary switch or binary? I suggest a trinary so you can protect your AC system and run electric fans when needed.

I forgot about the switch. Okay so I'll go with a trinary switch. That would be on the high side, right? Also, I currently do not have a fan. So, I would need to research all the wiring schematics for a fan.
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chevyman70 · 04-25-2013, 02:45 PM

Quote:

Originally Posted by ChevyCruizer

What AC system, stock 70's components with new style compressor, old air, etc? That will matter for both the refrigerant capacity as well as the amount of oil.

I usually take the oil capacity and split it between the compressor and the receiver dryer/accumulator. Usually more into the compressor and cycle the compressor by hand to "work it around". Don't "work" it too much or it will squirt out of the discharge port. Also when I first start the car (after charging the system) turn the AC on and off several times. On for 3 or 4 seconds (make sure the AC clutch is engaged) then turn it off quickly for 10 seconds. Do this several times to "work" the oil through the system.

Okay so I used another board member's suggestion. I am using a new evaporator from a 77 olds, acumulator from a 77 truck, nippodenso compressor, a new parallel condensor. The accumulator has a port for service and a port for a switch. I am not sure if a trinary switch would fit on it. I believe it's a 1/4 thread.
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ChevyCruizer · 04-26-2013, 11:44 AM

Yes, it goes on the high side. If the threads match up sure put it on the accumulator switch port.

I cant help with all of the AC parts from different cars, but it would be a good idea to back flush everything before you install it.

Another thing to remember is that some cans of refrigerant include an oil charge in them, so read the labels. I have never heard of anything bad coming from too much oil, but I figure a couple extra ounces of oil takes away that same amount of refrigerant capacity. Off the top of my head I think we usually add 5 ounces of oil into new compressors and 3 in other components. Research for yourself though.

Fans are easy. there are lots of threads on here about that.

Quote:

Originally Posted by chevyman70

I forgot about the switch. Okay so I'll go with a trinary switch. That would be on the high side, right? Also, I currently do not have a fan. So, I would need to research all the wiring schematics for a fan. The accumulator has a port for service and a port for a switch. I am not sure if a trinary switch would fit on it. I believe it's a 1/4 thread.

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chevyman70 · 05-07-2013, 12:40 AM

Okay so I installed everything, new hoses and all. Did a vacuum check using a small vacuum pump and ac gauges from harbor freight. It only pulled about 20 inches of vacuum. Once I closed all the valves, all the vacuum was lost in a matter of minutes. I checked all fittings and they are snugged. This would probably mean I have a leak, but where?
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**truckdude239** · 05-07-2013, 07:11 AM

Did you install new o rings?
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chevyman70 · 05-07-2013, 09:20 AM

All new rings, and lightly coated them with oil.
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**truckdude239** · 05-07-2013, 09:40 AM

Then you missed something or something is not right are these all new parts are any of them used?

chevyman70 · 05-07-2013, 10:24 AM

Quote:

Originally Posted by truckdude239

Then you missed something or something is not right are these all new parts are any of them used?

Everything is new with the exception of the compressor.
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ls1nova71 · 05-07-2013, 10:50 AM

It's going to be incredibly hard to find a leak under vacuum. You need to presurize the system and take a spray bottle of soapy water and start spraying all your connections, crimped hose ends ect. That said, I think A/C shops use nitrogen to fill the system since it doesn't retain moisture, but I have in the past used my air compressor, but it's not ideal, and you would at least need a drier in your air line to keep the moisture to a minimum. When I did it, I found my leak immediatley, it was at a welded fitting. then I vacuumed it down for a longer time than you normally would, just to make sure most of the moisture got boiled out. Hope this helps.

chevyman70 · 05-07-2013, 11:14 AM

Quote:

Originally Posted by ls1nova71

It's going to be incredibly hard to find a leak under vacuum. You need to presurize the system and take a spray bottle of soapy water and start spraying all your connections, crimped hose ends ect. That said, I think A/C shops use nitrogen to fill the system since it doesn't retain moisture, but I have in the past used my air compressor, but it's not ideal, and you would at least need a drier in your air line to keep the moisture to a minimum. When I did it, I found my leak immediatley, it was at a welded fitting. then I vacuumed it down for a longer time than you normally would, just to make sure most of the moisture got boiled out. Hope this helps.

Thanks! I'll try that. Just thinking out loud, when I placed the fitting in the hose, they didn't fit snugly, just slipped right in. I figured once the ac shop crimped them, they would tighten up. Is that how it works?
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chevyman70 · 05-07-2013, 07:40 PM

Another thing, I can install the quick disconnect coupler on the high side. On the low side, the coupler does not fit, so I just thread the hose to the port. Would that be a problem?
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ls1nova71 · 05-07-2013, 09:43 PM

Quote:

Originally Posted by chevyman70

Thanks! I'll try that. Just thinking out loud, when I placed the fitting in the hose, they didn't fit snugly, just slipped right in. I figured once the ac shop crimped them, they would tighten up. Is that how it works?
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Usually the ends are a prety snug fit and once you put them in, you almost can't get them back out. Sounds like you didn't have the right size hoses?

Quote:

Originally Posted by chevyman70

Another thing, I can install the quick disconnect coupler on the high side. On the low side, the coupler does not fit, so I just thread the hose to the port. Would that be a problem?
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Are you using R134a fittings? Your old accumulator would have R12 fitting and need an adapter.
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**truckdude239** · 05-07-2013, 10:13 PM

You need the retro fit kit with multiple size adpaters the r134 hoses should not screw on any fitting
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chevyman70 · 05-07-2013, 10:47 PM

Quote:

Originally Posted by ls1nova71

Usually the ends are a prety snug fit and once you put them in, you almost can't get them back out. Sounds like you didn't have the right size hoses?

Are you using R134a fittings? Your old accumulator would have R12 fitting and need an adapter.
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so this is what I have. The high pressure is for 134a, the low pressure is on the accumulator, its for r12 and r134a.

**truckdude239** · 05-08-2013, 01:40 AM

That one port is for the a/c pressure switch a oring goes in the groove try a low side fitting on the other fitting on the accumulator
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chevyman70 · 05-08-2013, 02:04 AM

Quote:

Originally Posted by truckdude239

That one port is for the a/c pressure switch a oring goes in the groove try a low side fitting on the other fitting on the accumulator
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I went and bought an adapter. I'll try vacuum test tomorrow again.
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l92Firebird · 05-08-2013, 06:58 AM

Did you do your own crimps on a/c lines or have a shop crimp them?

chevyman70 · 05-08-2013, 09:10 AM

Quote:

Originally Posted by l92Firebird

Did you do your own crimps on a/c lines or have a shop crimp them?

AC shop crimp them
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chevyman70 · 05-08-2013, 06:03 PM

Quote:

Originally Posted by ls1nova71

Usually the ends are a prety snug fit and once you put them in, you almost can't get them back out. Sounds like you didn't have the right size hoses?

Are you using R134a fittings? Your old accumulator would have R12 fitting and need an adapter.
Posted via Mobile Device

I called AP Air, they said that the fittings fit loosely on the hose til crimp. I haven't checked for leaks, but I am hoping its not that where's leaking.
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chevyman70 · 05-09-2013, 12:49 AM

Quote:

Originally Posted by ls1nova71

It's going to be incredibly hard to find a leak under vacuum. You need to presurize the system and take a spray bottle of soapy water and start spraying all your connections, crimped hose ends ect. That said, I think A/C shops use nitrogen to fill the system since it doesn't retain moisture, but I have in the past used my air compressor, but it's not ideal, and you would at least need a drier in your air line to keep the moisture to a minimum. When I did it, I found my leak immediatley, it was at a welded fitting. then I vacuumed it down for a longer time than you normally would, just to make sure most of the moisture got boiled out. Hope this helps.

I found where it was leaking. The high side compressor adapter is leaking. It turns out that the adapter does not perfectly align to the compressor's thread. It kinks when I tighten it up.
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**Clyde65** · 05-09-2013, 08:56 AM

http://67-72chevytrucks.com/vboard/s...d.php?t=523462

chevyman70 · 05-13-2013, 11:14 PM

So I am extremely frustrated at this point. No mater what I do to the fitting, it LEAKS! I called several places to see if they carry them, and they all say they no longer carry them. I saw the website from transair but their fittings look like this. Any other suggestions! I am almost giving up at this point.

04-24-2013, 09:59 PM	#1
chevyman70 Registered User Join Date: May 2002 Location: Lakewood, CA Posts: 194	Getting A/C going for first time on 5.3l Okay, I am starting to get my AC parts together for my 5.3l swap. I know I need freon 134r and PAG oil (which weight?). I am using the nippodenso compressor. What do I first? Where do I add the oil, and how much freon do I need?

04-25-2013, 08:20 AM	#2
Clyde65 1965 Chevy C10, 2005 4.8L/4l60 Join Date: Aug 2004 Location: DFW Texas Posts: 8,546	Re: Getting A/C going for first time on 5.3l Its cheap enough to take what you have to a shop that specializes in AC work, have them charge it. Also did you use a trinary switch or binary? I suggest a trinary so you can protect your AC system and run electric fans when needed. __________________ Clyde65 Rebuild of Clyde http://67-72chevytrucks.com/vboard/s...84#post8338184 69 Aristocrat Lo Liner build http://67-72chevytrucks.com/vboard/s...84#post7561684 *support our troops!*

05-07-2013, 12:40 AM	#7
chevyman70 Registered User Join Date: May 2002 Location: Lakewood, CA Posts: 194	Re: Getting A/C going for first time on 5.3l Okay so I installed everything, new hoses and all. Did a vacuum check using a small vacuum pump and ac gauges from harbor freight. It only pulled about 20 inches of vacuum. Once I closed all the valves, all the vacuum was lost in a matter of minutes. I checked all fittings and they are snugged. This would probably mean I have a leak, but where? Posted via Mobile Device

05-07-2013, 07:11 AM	#8
truckdude239 Senior Member Join Date: Sep 2005 Location: Lewisville, Nc Posts: 10,237	Re: Getting A/C going for first time on 5.3l Did you install new o rings? Posted via Mobile Device __________________ David fuller Ase Certified Mechanic Click here to help support our board!! 1971 Chevy c-10 under going a 4.8l LSx swap Build Thread http://67-72chevytrucks.com/vboard/s...d.php?t=421305 2007 Honda Accord my daily 145kmiles 2002 Honda Accord 4 door With 330k(sisters car) 2005 toyota Avalon 228k( brothers car) 2002 Sububran 5.3 245k 2000 Tahoe 5.3l 378 General manager for Marco's Carwash & lube

05-07-2013, 09:20 AM	#9
chevyman70 Registered User Join Date: May 2002 Location: Lakewood, CA Posts: 194	Re: Getting A/C going for first time on 5.3l All new rings, and lightly coated them with oil. Posted via Mobile Device

05-07-2013, 09:40 AM	#10
truckdude239 Senior Member Join Date: Sep 2005 Location: Lewisville, Nc Posts: 10,237	Re: Getting A/C going for first time on 5.3l Then you missed something or something is not right are these all new parts are any of them used? __________________ David fuller Ase Certified Mechanic Click here to help support our board!! 1971 Chevy c-10 under going a 4.8l LSx swap Build Thread http://67-72chevytrucks.com/vboard/s...d.php?t=421305 2007 Honda Accord my daily 145kmiles 2002 Honda Accord 4 door With 330k(sisters car) 2005 toyota Avalon 228k( brothers car) 2002 Sububran 5.3 245k 2000 Tahoe 5.3l 378 General manager for Marco's Carwash & lube

05-07-2013, 10:50 AM	#12
ls1nova71 Registered User Join Date: Dec 2009 Location: Independence Mo Posts: 4,118	Re: Getting A/C going for first time on 5.3l It's going to be incredibly hard to find a leak under vacuum. You need to presurize the system and take a spray bottle of soapy water and start spraying all your connections, crimped hose ends ect. That said, I think A/C shops use nitrogen to fill the system since it doesn't retain moisture, but I have in the past used my air compressor, but it's not ideal, and you would at least need a drier in your air line to keep the moisture to a minimum. When I did it, I found my leak immediatley, it was at a welded fitting. then I vacuumed it down for a longer time than you normally would, just to make sure most of the moisture got boiled out. Hope this helps. __________________ My '72 short bed build. http://www.ls1tech.com/forums/conver...6-0-4l80e.html 5.3 swap into my RUSTY '71 C10 http://ls1tech.com/forums/conversion...71-c-10-a.html

05-07-2013, 07:40 PM	#14
chevyman70 Registered User Join Date: May 2002 Location: Lakewood, CA Posts: 194	Re: Getting A/C going for first time on 5.3l Another thing, I can install the quick disconnect coupler on the high side. On the low side, the coupler does not fit, so I just thread the hose to the port. Would that be a problem? Posted via Mobile Device

05-07-2013, 10:13 PM	#16
truckdude239 Senior Member Join Date: Sep 2005 Location: Lewisville, Nc Posts: 10,237	Re: Getting A/C going for first time on 5.3l You need the retro fit kit with multiple size adpaters the r134 hoses should not screw on any fitting Posted via Mobile Device __________________ David fuller Ase Certified Mechanic Click here to help support our board!! 1971 Chevy c-10 under going a 4.8l LSx swap Build Thread http://67-72chevytrucks.com/vboard/s...d.php?t=421305 2007 Honda Accord my daily 145kmiles 2002 Honda Accord 4 door With 330k(sisters car) 2005 toyota Avalon 228k( brothers car) 2002 Sububran 5.3 245k 2000 Tahoe 5.3l 378 General manager for Marco's Carwash & lube

05-08-2013, 01:40 AM	#18
truckdude239 Senior Member Join Date: Sep 2005 Location: Lewisville, Nc Posts: 10,237	Re: Getting A/C going for first time on 5.3l That one port is for the a/c pressure switch a oring goes in the groove try a low side fitting on the other fitting on the accumulator Posted via Mobile Device __________________ David fuller Ase Certified Mechanic Click here to help support our board!! 1971 Chevy c-10 under going a 4.8l LSx swap Build Thread http://67-72chevytrucks.com/vboard/s...d.php?t=421305 2007 Honda Accord my daily 145kmiles 2002 Honda Accord 4 door With 330k(sisters car) 2005 toyota Avalon 228k( brothers car) 2002 Sububran 5.3 245k 2000 Tahoe 5.3l 378 General manager for Marco's Carwash & lube

05-08-2013, 06:58 AM	#20
l92Firebird Registered User Join Date: Sep 2010 Location: Planet Earth Posts: 13	Re: Getting A/C going for first time on 5.3l Did you do your own crimps on a/c lines or have a shop crimp them?

05-09-2013, 08:56 AM	#24
Clyde65 1965 Chevy C10, 2005 4.8L/4l60 Join Date: Aug 2004 Location: DFW Texas Posts: 8,546	Re: Getting A/C going for first time on 5.3l http://67-72chevytrucks.com/vboard/s...d.php?t=523462 __________________ Clyde65 Rebuild of Clyde http://67-72chevytrucks.com/vboard/s...84#post8338184 69 Aristocrat Lo Liner build http://67-72chevytrucks.com/vboard/s...84#post7561684 *support our troops!*

05-13-2013, 11:14 PM	#25
chevyman70 Registered User Join Date: May 2002 Location: Lakewood, CA Posts: 194	Re: Getting A/C going for first time on 5.3l So I am extremely frustrated at this point. No mater what I do to the fitting, it LEAKS! I called several places to see if they carry them, and they all say they no longer carry them. I saw the website from transair but their fittings look like this. Any other suggestions! I am almost giving up at this point. Attached Images



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