Discharge pipe burst - add how much oil?

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Swedal
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Discharge pipe burst - add how much oil?

Post by Swedal »

Car is a Ford Focus 2009 with factory charge 600 grams and 200 ml PAG oil. After replacing the discharge pipe that had a big crack in it 5 inch from outlet I wonder hos much oil I need to add. I could see oil sprayed out but impossible to tell exactly hos much. I just added about 40 ml but I think I need more. What do you think? Could I have lost half the oil charge due to the worst possible place for it to leak?
Al9
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Re: Discharge pipe burst - add how much oil?

Post by Al9 »

Do yourself a favor, flush the system, get a new dryer fitted and start with a system oil charge inside the compressor. Any commercial double end capped PAG 46 oil will be more than enough, no need for ZXL100PG or Ford's stuff.

The risk of getting too much oil inside and suffering warmer vent temps or getting too little oil and suffering compressor seizure is simply too high. Simply no way to know how much oil you lost.
Swedal
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Re: Discharge pipe burst - add how much oil?

Post by Swedal »

I know that is the correct way to do it but try to convince someone that you need to spend several hours more when the problem was fixed in 15 minutes. That is simply not going to happen. I will have to guesstimate the loss of oil.
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Cusser
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Re: Discharge pipe burst - add how much oil?

Post by Cusser »

Swedal wrote:Car is a Ford Focus 2009 with factory charge 600 grams and 200 ml PAG oil. After replacing the discharge pipe that had a big crack in it 5 inch from outlet I wonder hos much oil I need to add. I could see oil sprayed out but impossible to tell exactly how much. I just added about 40 ml but I think I need more. What do you think? Could I have lost half the oil charge due to the worst possible place for it to leak?
Yes, I think that with a large leak/sudden leak like that you could lose at least half your oil.

I understand that flushing to get most of the remaining oil out is time consuming but the correct way; wonder if worthwhile to take off the compressor and drain to see if ANY oil is in there. I've seen compressors with zero remaining oil.

If mine, I'd also guess, but I would add at least 100ml new oil, not 40ml.
Al9
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Re: Discharge pipe burst - add how much oil?

Post by Al9 »

Yes, OP should expect to find very little oil inside it too. Running the A/C with way low refrigerant (the typical "something's hissing under the dash when AC/defroster is on" condition) is what sends most of the oil to the evaporator. Having a TXV means that the compressor is able to run with very little refrigerant inside.

The amazing fact is that the compressor may still not seize up, even if all moving parts within are taking a real beating when running like this.
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bohica2xo
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Re: Discharge pipe burst - add how much oil?

Post by bohica2xo »

Do it right, do it once.

Or do it over & over.

When the compressor fails, the shards will block a few passages in the condenser. Then the performance with the new compressor will be poor...
Swedal
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Re: Discharge pipe burst - add how much oil?

Post by Swedal »

Al9 wrote:Yes, OP should expect to find very little oil inside it too. Running the A/C with way low refrigerant (the typical "something's hissing under the dash when AC/defroster is on" condition) is what sends most of the oil to the evaporator. Having a TXV means that the compressor is able to run with very little refrigerant inside.

The amazing fact is that the compressor may still not seize up, even if all moving parts within are taking a real beating when running like this.
Yes car ACs seems to tolerate alot of abuse. I think I'll add another 60 ml then. If that is too much and I loose a few % cooling that does not matter much here in Sweden where we need AC two weeks a year.
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