Where do people get these ideas?

[Chris142]

Working in the auto repair industry has definitely brought up some strange things people do.

Had a real " you did what" moment yesterday. Apparently a guys ac compressor locked up. He put a new compressor on the car. But before he did he drained the used oil from the old compressor that blew up and put it into the new compressor.

Now the new compressor has also failed and he asked us if we knew why. So let's see. Used and contaminated oil, likely not enough oil,no new reciever dryer/ accumulator,no flush or condenser replacement if needed and we are not even talking about the expansion valve,hoses or evaporator yet!

Now it has 2 colossal failures and the thing won't ever be right unless most everything in that system is replaced.

 

[talest]

At first, I had to figure out you were talking about compressor oil. My first thought was refrigerant but, alas, yes they do use oil. I always thought they come pre-oiled.

So you are saying he put on a new compressor. If his new compressor came pre-oiled as I believe they all do, though I do not have any firsthand experience, only what I read.. then it was instantly over-oiled before any refrigerant even went in.

Hopefully a deep vacuum was pulled and all contaminants and moisture got out of the system. If there was a leak in the system, then maybe the system went flat and all contaminants and moisture leaked out. However, there are even little cans of additional oil (Ester oil if R-12, Ester OR PAG oils if R-134) that can be added in even additionally. I have heard of a compressor being able to be over-oiled but also in that they are like Glocks, prefer to be run with less oil than more.

So, you are saying he over-oiled the compressor is the source of the failure? The compressor locked up? (this you indicated, if it will spin again..) It will not spin anymore? Pulled a vacuum and put the gauges on it first before telling him he is not allowed to touch his own stuff?

 

[Omahaug]

It's completely mind boggling. Especially since almost all A/C compressors you buy, literally have multiple warnings in the instructions, the manuals, even attached to the unit, about cleaning the A/C system or outright replacing the lines, the receiver-drier or accumulator, everything. The manufacturers know how many failures they get from people doing stupid stuff like this so they try to pre-empt it, yet people still do it.

 

[kschachn]

Wow take a breath there, talest.

A locked up compressor is a sign of a catastrophic mechanical failure and often includes metallic debris shedding in the process. This will contaminate the entire system, and at a minimum it must be flushed and re-oiled. The reason you dump out the oil from the failed compressor is not so that you can put the drained oil in the new one, it is to determine the amount present so you can add that to the new component. If you have ever done any air conditioning work (which I'm assuming you haven't), you would see in the manufacturer's literature that they do not ship the new compressor with the correct amount of oil. You are supposed to measure the amount in the old one, drain out the oil from the new part and add the correct amount of new oil back in.

Proper evacuation of the system is not the concern here, metallic debris in the system is. You have to replace every single component or properly flush the lines, evaporator, and the condenser and replace the compressor, receiver/dryer and expansion valve (and orifice if there is one). Otherwise the new compressor is likely to fail in short order.

Pouring oil from the failed compressor into the new one is just about the worst thing anyone could do and shows a complete lack of understanding.

 

[talest]

Originally Posted by kschachn
Wow take a breath there, talest.

A locked up compressor is a sign of a catastrophic mechanical failure and often includes metallic debris shedding in the process. This will contaminate the entire system, and at a minimum it must be flushed and re-oiled. The reason you dump out the oil from the failed compressor is not so that you can put the drained oil in the new one, it is to determine the amount present so you can add that to the new component. If you have ever done any air conditioning work (which I'm assuming you haven't), you would see in the manufacturer's literature that they do not ship the new compressor with the correct amount of oil. You are supposed to measure the amount in the old one, drain out the oil from the new part and add the correct amount of new oil back in.

Proper evacuation of the system is not the concern here, metallic debris in the system is. You have to replace every single component or properly flush the lines, evaporator, and the condenser and replace the compressor, receiver/dryer and expansion valve (and orifice if there is one). Otherwise the new compressor is likely to fail in short order.

Pouring oil from the failed compressor into the new one is just about the worst thing anyone could do and shows a complete lack of understanding.


Thanks for the clarification, kschachn.

Want to quickly add that it appears source-specific on if the compressor comes with oil or not. https://www.classicautoair.com/do-i-need-to-add-oil-to-my-air-conditioning-compressor/

Quote
July 15, 2014
DO I NEED TO ADD OIL TO MY AIR CONDITIONING COMPRESSOR?
Customers often ask whether or not they need to add oil to an air conditioning compressor they purchase from us. This question comes up because people want to avoid poor cooling or failure problems resulting from improper oil levels. Fortunately most people realize the harm to the system and potential danger of running an AC compressor with no oil.

Classic Auto Air sells new rotary (Sanden style) compressors in 2 variations: those that are compatible with the older, R12 refrigerant and compressors compatible with 134a refrigerant. In addition, we also rebuild compressors that customers send in.

In all cases, Classic Auto Air customers receive a compressor that is fully charged WITH THE APPROPRIATE AMOUNT OIL.

Compressors that Classic Auto Air rebuilds come with a full system charge of Ester 100 oil, which is compatible with both the old R12 refrigerant and newer 134a. New, R12 Rotary compressors come with a full system charge of Mineral Oil, which is compatible only with R12 refrigerant. New 134a rotary compressors come with a full system charge of PAG oil, which is compatible only with 134a refrigerant.

If your compressor is going into a system that has previously been installed, it's important to get as much of the original oil charge out of the system as possible to protect against an oil overcharge. It's typically ok for an extra ounce or two of oil to remain in the system, provided it is contaminant free. A significant overcharge of oil (over 2 ounces) however, can cause multiple problems, including inefficient cooling and immediate or premature compressor failure.

As stated above, it is important to fully evacuate your air conditioning system to assure that any contaminants have been removed before attaching a new compressor. Contamination is one of the biggest causes of component failure. Failure to ensure the system is contaminant free can cause your newly replaced compressor (and other components) to fail and void component warranty.

 

[ragtoplvr]

The last compressor I replaced was a R4 GM and it had notes not to rotate it until installed as the cylinders were full of oil, Then you were to rotate by hand at least 3 complete revolutions. Flush system, new drier and fill with R12 (it was a long time ago). Lasted at least 5 summers since then, until I sold it. OE never made more than half of the second summer. *^ Monte Carlo SS, AKA the black lemon. I did finally fix all the issues.

Rod

 

[Yah-Tah-Hey]

Originally Posted by Chris142
Working in the auto repair industry has definitely brought up some strange things people do.

Had a real " you did what" moment yesterday. Apparently a guys ac compressor locked up. He put a new compressor on the car. But before he did he drained the used oil from the old compressor that blew up and put it into the new compressor.

Now the new compressor has also failed and he asked us if we knew why. So let's see. Used and contaminated oil, likely not enough oil,no new reciever dryer/ accumulator,no flush or condenser replacement if needed and we are not even talking about the expansion valve,hoses or evaporator yet!

Now it has 2 colossal failures and the thing won't ever be right unless most everything in that system is replaced.

From that three pound blob between their ears. Same place every good and bad ideas originate. Or put another way, from ten billion neural connections.

 

[bdcardinal]

I have seen compressors come both with and without oil, even from Ford. Mazda ones generally come dry since most come from Japan and they would have to classify the entire shipment as HAZMAT if they come with oil.

 

[bdcardinal]

O and you haven't seen wacky ideas until you work with car salesmen. They will walk in and begin with "so we have this idea" and I cut them off and say "no, I don't need to hear it and already know it is a bad idea."

 

[97prizm]

You want to see bad ideas? Try working as an emissions Inspector. People routinely come in and say "you see it's not broken but to start my car all you have to do is....." Ive seen seats recovered in shower curtain. Shoot a lady came in Monday speaking almost no English with a check engine light on. She handed a guy $3,000 and drove home and he's long gone while her car wont pass emissions.

 

[TMoto]

Kinda feel bad for the guy wasting all that time and money without researching what he was getting into. I usually do most of my own work but A/C is one area I leave to the pros.