Chevy Impala SS Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
95 Posts
Discussion Starter #1
Turned on the AC only to discover that the air was not blowing cold. Opened the hood and noticed that the clutch on the compressor was not engaging. What to do? Replace the compressor? Replace the clutch that is on the pulley? This is on a bone stock 96 BBB with 119k on the odo. Compressor is original.
 

·
Super Moderator
Joined
·
5,767 Posts
1. Check pressure.
2. Test compressor engagement.
3. Find leak.
4. Fix leak.
5. Fill.
6. Be cool.

The how to for 1-4 can be found by a quick search. I've explained 1 and 2 for sure.
 

·
Registered
Joined
·
3,505 Posts
Don't do it yourself. Take it to a shop. In the long run, it is cheaper than screwing around and not getting it right. They can find the leak fast and fix it and you will be on your way. With that low mileage, it is unlikely that it is a bad compressor. the accumulator and orifice tube and even the clutch are cheap parts.
 

·
Banned
Joined
·
3,437 Posts
Turned on the AC only to discover that the air was not blowing cold. Opened the hood and noticed that the clutch on the compressor was not engaging. What to do? Replace the compressor? Replace the clutch that is on the pulley? This is on a bone stock 96 BBB with 119k on the odo. Compressor is original.
you say the original ac compressor well my guess is the compressor seals are leaking or another leak . that happened to me about 4 yrs ago. at that time 70K miles.

what I saw was some odd looking oil drip on my driveway . normally no drips on my pavement. what happened was the compressor seals leaked the compressor ref oil which is this greenish like color and then the compressor locked up.

the compressor will not turn on unless the system has pressure. this is to protect the compressor from damage because the compressor requires refrigerant to be lubed.
if you can do it add 12OZ of 134 to the system with leak detector . then using a black [UV] light find the leak.

if not have ac shop find and fix the leak.

if the compressor is the problem you will have to get a HVAC tech to do the replacing. requires a lot of special tools and vacuum pumps etc..
I have done ac work for a few decades so for me I have these tools . the compressor if bad is not an easy job to replace properly the rear mounting ear is a PITA to lock down correctly if not done right it can damage the compressor seals .
 

·
Registered
Joined
·
8,199 Posts
....
if you can do it add 12OZ of 134 to the system with leak detector . then using a black [UV] light find the leak.

......
You did not mention if any recharging or repairs in the near (as in this time last year) or the distant past. Depending whether a DIY type, or usually defaulting to a shop, you've been given 2 good directions. I've been adding a can+/- each Spring for the past 8 years. Just did it last w/e with the toasty temps. I used to use a simple hose w/o gauge and quit adding as soon as the clutch stayed on fulltime. For several years I've used a setup with straighforward gauge with variable pressure range display according to outside temperature.
 

·
Banned
Joined
·
3,437 Posts
The system as designed does leak small amounts at the shaft seal esp in the cold north during the winter when the vehicle sits for periods of time. this is because the oil drys out from the seals and then small weeps of refrigerant. I have seen over a very long time adding 1/2 of a 12 oz can gets it back to proper cooling. using no gauges when adding is guessing but it can be done.

if the air temp is 80 deg F set the ac to max blower speed and the doors all open. set idle rpm to 1100 RPM. as you add refrigerant wait until the secondary fan starts to run. when that happens @80 deg F air temp then you are very close to the correct amount in the system.

I did have gauges on vehicle hi/lo side ports to confirm this.

leaks as I said are the compressor shaft seal on this type system.. what also does leak is the low/high side pressure ports as well as the low pressure switch port.

I had to re charge my impala last year because that low pressure switch O ring was defective it was part of the new filter dryer I installed 4 yrs ago. I had to add 1.5 cans of r134 because of that leak.. since I installed leak detector the leak was easy to find quickly when I did the compressor replacing.
 

·
Registered
Joined
·
10,948 Posts
Before I had the proper requirement I played around with cans. First of all the cans with the gauge cost too much, they have some bogus additives and alot have some ?? oil or worse LEAK SEALER. Small quantities but still.. You always wind up over charging with the can. If the system is leaking, it has moisture and some air in it, no questions asked. When I first recovered my can charged system the vacuum pump oil contaminated BAD with moisture

If you care to fix it right Look for a leak with a UV light or a sniffer The factory AC fill has a UV dye in it already. At least it did on my car. About 4 points were lit up like Christmas. Case seals on the compressor, shaft seal on the compressor, high and low valves. Its good to change BOTH service valves. The low side is just a screw in schrader like a tire, but its for AC. Don't use a tire one. The High side requires a special 8 sided socket. All valves leak with age. People put the can up to the low side valve, the effen valve will just leak and will never seal again from age. . I had it happen many times on many vehicles.


Recover. Repair leak, Vacuum, note that it holds a vacuum. Charge Charge it with a scale or a fancy machine... get a good R-134a cylinder when you can, probably it will be banned soon Spend $100- 130 , 30lbs, it will last forever,.. Anyone can buy it license or not. Some stores are A holes and I have to prove myself that its not r-12 . And I do have a card

I would also recommend maybe throwing a new orifice valve on it. PITA, need to remove the battery to get at it.... The drier, accumulator ahh. I would leave it . Think the new Chinese ones are better than the OEM one? Ill try to run the OEM one as long as possible.. Cleaner the orifice valve, better AC performance.

I don't buy a system needed a fill from time and leakage. That's 1970s talk. I have a 11 year old 130k vehicle here that has been running the AC every day for hours and hours since it was new. It does not need a top off. That whole "the compressor shat seal leaks oil and refrigerant to lubricate...." is bs If it leaks, you have a leak. :) Snoop around and you will find a leak on that "It only needed a top off" system

if you search around you can probably find some shop who will Service the AC for 60 or less . The people who want 80-90 can screw off.
 

·
Registered
Joined
·
8,199 Posts
Don't take this wrong, but can you confirm whether you followed any of the recommendations 5 guys have (lengthily and with particular detail) already posted? Absence of comment about relays would already indicate leak/low refrigerant being much more likely cause of your symptoms than mech. failure.
 

·
Registered
Joined
·
95 Posts
Discussion Starter #10
No offense taken. Have already made an appointment to have the system checked by a local shop. All the input is always greatly appreciated and yet another example why I always come to the SS forum first.
 

·
Banned
Joined
·
3,437 Posts
No offense taken. Have already made an appointment to have the system checked by a local shop. All the input is always greatly appreciated and yet another example why I always come to the SS forum first.
bring to the AC shop as you plan , and post what they found .

the relay or some electrical failure could be the problem possibly.
however the system does leak , this is not a sealed type system. it is not like your refrigerator .

someone stated that shaft seal does not leak well it does after 10 plus years this is from the temperature extremes .. so most do have to put in some refrigerant after a year or two when they get this old.

yes these are very old vehicles some of the components used during this time where not all that up on leak prevention , which is why in 1996 GM changed from R12 to R134 a safe refrigerant for the atmosphere to prevent ozone damage to it.

then some time after 1996 the compressor design changed to be a much better sealed design. my 2000 GM truck has this new type and it is performing very well with extremely little leakage. last time I added was 5 yrs ago. 170K miles.
 

·
Banned
Joined
·
3,437 Posts
So can I assume that my car has....err, had the R134 refrigerant when it came from the factory?
I think I have stated that these are R134 refrigerants . 1996 GM impala/caprice.

my 1996 was manufactured in Arlington TX in sept 20 ,1995

purchased in nov 1995.
 
1 - 14 of 14 Posts
Top