New A/C compressor help
Thread Starter
Instructor
Joined: May 2011
Posts: 103
Likes: 2
New A/C compressor help
I am changing the A/C system over to 134 in my 87' and I am replacing the compressor, accumulator/drier, orriface tube and main compressor hose and am looking for some help. I was wondering where to add the oil at.
Do I just pour it in the compressor where the main hose attaches in the back of the compressor, I didn't see a fill plug and the same with the drier...just pour it in?
There was no oil in the old compressor or drier that I noticed.
I know this sounds like a dumb question, but I don't want screw up my system.
After I flush the evaporator and condensor, should I add a little oil to those too?
And after the oil is added and system all back together do I need to pull a vacuum before charging?
Thanks
Do I just pour it in the compressor where the main hose attaches in the back of the compressor, I didn't see a fill plug and the same with the drier...just pour it in?
There was no oil in the old compressor or drier that I noticed.
I know this sounds like a dumb question, but I don't want screw up my system.
After I flush the evaporator and condensor, should I add a little oil to those too?
And after the oil is added and system all back together do I need to pull a vacuum before charging?
Thanks
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
After everythng has been blown clean, or unsealed new, ALWAYS add 1-2 oz to the compressor suction port and then rotate the compressor with a wrench/socket 10 full revolutions to spread the oil and lube the shaft seal.
When you flush, blow each section of the system with compressed air until the
air compressor wears out ! Especially the evaporator...the air that you blow in one side is so diffused at the far end that there is barely any pressure escaping so its very hard to get ALL the flush crap out with any debris that its loosened and dissolved. Blow the evap for a long long time...
Yes, unless you live in the dessert (near zero humidity) you MUST evacuate the system to get all the moisture out. Moisture and 134a make corrosives. It does not cool well either.
Vac also is the test to see if you have leaks. Getting the vac to -29hg and having that hold tells you the seals are all ok. If it leaks down then you do not want to waste gas on that yet....
AutoZone has vac pumps and gauges for rent.
Know how much oil your particular system requires...do NOT overfill!
Mine takes approx 6oz IIRC (87)
add an oz to the evap tube before dropping the orifice in place.
add some to the condensor.
Pour whats left in the accum/dryer.
When its all assembled and before the belt is installed, again, rotate the compressor to make sure there are no pockets of fluid that have not dispersed. Add belt and charge.
The oil is spread by the gas as it travels. Its stored in the accumalator. Adding too much causes poor cooling since the gas is unable to expand as a gas when its too full of oil...too little oil causes premature wear.
The key to this is cleanliness and sealing. I wipe oil on all the O-rings before tightening fittings. You do not want to pour a large amount of the oil in any single place....spread it around. 6 or 8 oz isn;t that much, so measure well and add at each opening then close it up.
Do search and find out exacltly how much your system needs...
When you flush, blow each section of the system with compressed air until the
air compressor wears out ! Especially the evaporator...the air that you blow in one side is so diffused at the far end that there is barely any pressure escaping so its very hard to get ALL the flush crap out with any debris that its loosened and dissolved. Blow the evap for a long long time...
Yes, unless you live in the dessert (near zero humidity) you MUST evacuate the system to get all the moisture out. Moisture and 134a make corrosives. It does not cool well either.
Vac also is the test to see if you have leaks. Getting the vac to -29hg and having that hold tells you the seals are all ok. If it leaks down then you do not want to waste gas on that yet....
AutoZone has vac pumps and gauges for rent.
Know how much oil your particular system requires...do NOT overfill!
Mine takes approx 6oz IIRC (87)
add an oz to the evap tube before dropping the orifice in place.
add some to the condensor.
Pour whats left in the accum/dryer.
When its all assembled and before the belt is installed, again, rotate the compressor to make sure there are no pockets of fluid that have not dispersed. Add belt and charge.
The oil is spread by the gas as it travels. Its stored in the accumalator. Adding too much causes poor cooling since the gas is unable to expand as a gas when its too full of oil...too little oil causes premature wear.
The key to this is cleanliness and sealing. I wipe oil on all the O-rings before tightening fittings. You do not want to pour a large amount of the oil in any single place....spread it around. 6 or 8 oz isn;t that much, so measure well and add at each opening then close it up.
Do search and find out exacltly how much your system needs...
Last edited by leesvet; Jun 30, 2012 at 09:51 PM.
Pro
Joined: Jan 2009
Posts: 686
Likes: 4
From: Austin Texas
I am changing the A/C system over to 134 in my 87' and I am replacing the compressor, accumulator/drier, orriface tube and main compressor hose and am looking for some help. I was wondering where to add the oil at.
Do I just pour it in the compressor where the main hose attaches in the back of the compressor, I didn't see a fill plug and the same with the drier...just pour it in?
There was no oil in the old compressor or drier that I noticed.
I know this sounds like a dumb question, but I don't want screw up my system.
After I flush the evaporator and condensor, should I add a little oil to those too?
And after the oil is added and system all back together do I need to pull a vacuum before charging?
Thanks
Do I just pour it in the compressor where the main hose attaches in the back of the compressor, I didn't see a fill plug and the same with the drier...just pour it in?
There was no oil in the old compressor or drier that I noticed.
I know this sounds like a dumb question, but I don't want screw up my system.
After I flush the evaporator and condensor, should I add a little oil to those too?
And after the oil is added and system all back together do I need to pull a vacuum before charging?
Thanks
Thread Starter
Instructor
Joined: May 2011
Posts: 103
Likes: 2
After everythng has been blown clean, or unsealed new, ALWAYS add 1-2 oz to the compressor suction port and then rotate the compressor with a wrench/socket 10 full revolutions to spread the oil and lube the shaft seal.
When you flush, blow each section of the system with compressed air until the
air compressor wears out ! Especially the evaporator...the air that you blow in one side is so diffused at the far end that there is barely any pressure escaping so its very hard to get ALL the flush crap out with any debris that its loosened and dissolved. Blow the evap for a long long time...
Yes, unless you live in the dessert (near zero humidity) you MUST evacuate the system to get all the moisture out. Moisture and 134a make corrosives. It does not cool well either.
Vac also is the test to see if you have leaks. Getting the vac to -29hg and having that hold tells you the seals are all ok. If it leaks down then you do not want to waste gas on that yet....
AutoZone has vac pumps and gauges for rent.
Know how much oil your particular system requires...do NOT overfill!
Mine takes approx 6oz IIRC (87)
add an oz to the evap tube before dropping the orifice in place.
add some to the condensor.
Pour whats left in the accum/dryer.
When its all assembled and before the belt is installed, again, rotate the compressor to make sure there are no pockets of fluid that have not dispersed. Add belt and charge.
The oil is spread by the gas as it travels. Its stored in the accumalator. Adding too much causes poor cooling since the gas is unable to expand as a gas when its too full of oil...too little oil causes premature wear.
The key to this is cleanliness and sealing. I wipe oil on all the O-rings before tightening fittings. You do not want to pour a large amount of the oil in any single place....spread it around. 6 or 8 oz isn;t that much, so measure well and add at each opening then close it up.
Do search and find out exacltly how much your system needs...
When you flush, blow each section of the system with compressed air until the
air compressor wears out ! Especially the evaporator...the air that you blow in one side is so diffused at the far end that there is barely any pressure escaping so its very hard to get ALL the flush crap out with any debris that its loosened and dissolved. Blow the evap for a long long time...
Yes, unless you live in the dessert (near zero humidity) you MUST evacuate the system to get all the moisture out. Moisture and 134a make corrosives. It does not cool well either.
Vac also is the test to see if you have leaks. Getting the vac to -29hg and having that hold tells you the seals are all ok. If it leaks down then you do not want to waste gas on that yet....
AutoZone has vac pumps and gauges for rent.
Know how much oil your particular system requires...do NOT overfill!
Mine takes approx 6oz IIRC (87)
add an oz to the evap tube before dropping the orifice in place.
add some to the condensor.
Pour whats left in the accum/dryer.
When its all assembled and before the belt is installed, again, rotate the compressor to make sure there are no pockets of fluid that have not dispersed. Add belt and charge.
The oil is spread by the gas as it travels. Its stored in the accumalator. Adding too much causes poor cooling since the gas is unable to expand as a gas when its too full of oil...too little oil causes premature wear.
The key to this is cleanliness and sealing. I wipe oil on all the O-rings before tightening fittings. You do not want to pour a large amount of the oil in any single place....spread it around. 6 or 8 oz isn;t that much, so measure well and add at each opening then close it up.
Do search and find out exacltly how much your system needs...
thats exactly what I was looking for. Good information. Thanks for the help, very much appreciated.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
System capacity is 8 ozs. Put 4 in the compressor and turn the shaft as outlined. Drain and repeat leaving 4 ozs in it. You do this because a quality rebuild or new comes with oil in it - only you don't know what it is - and this ensures that there is only one type of oil.
Put the other 4 ozs in a new Accumulator.
Put the other 4 ozs in a new Accumulator.
