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Overfill of AC ester oil, r12 to r134 conversion

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Old 07-08-2018 | 09:53 AM
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Default Overfill of AC ester oil, r12 to r134 conversion

Unfortunately I filled the compressor with 9-10 ounces of ester oil instead of the recommended 5-6. I have replaced the compressor, drier and the hoses for a r134 conversion on a 86.5 with only front AC. Should I drain off some of the oil? Or is it ok? I would rather not take off the compressor with the hoses ++.
Old 07-08-2018 | 11:12 AM
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Originally Posted by ihoe
Unfortunately I filled the compressor with 9-10 ounces of ester oil instead of the recommended 5-6. I have replaced the compressor, drier and the hoses for a r134 conversion on a 86.5 with only front AC. Should I drain off some of the oil? Or is it ok? I would rather not take off the compressor with the hoses ++.
you have to drain the oil, sorry don't run the a.c. with that much oil will damage the system, drain it start over.
Old 07-08-2018 | 01:24 PM
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I don't have the component capacities handy, but... The amount you put in the compressor should be the amount listed for all the components you replaced. Since you replaced the drier and hoses along with the compressor, you get to put all that oil in the compressor. Spin the compressor by hand to make sure there are no cylinders full of oil before you engage the clutch. The oil will find its way to where it needs to be. From foggy memory (almost 20 years now since I did that project...) I don't think you are far off the target numbers.

The risk with a little extra oil is that it can coat the heat exchangers and slow heat transfer. Extra oil doesn't puddle up in the compressor once you've cleared the cylinders and run the system. The biggest repository for oil after the compressor "sump" is the dessicant bag in the drier. Extra stuff usually ends up there after the system has run some, and in extreme cases may end up puddling the bottom of the evaporator. In one of those odd head-scratching phenomena, the oil is hygroscopic, and the moisture in the oil promotes corrosion in the aluminum evaporator over time. It takes a lot more than you've put in to get there though.
Old 07-08-2018 | 02:27 PM
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Per the tech bulletin, you should have added 4.6 oz; and it allows for a 10% +/- variance. Since you're at +50%, if you haven't added the R134 and you just added the oil by dripping it down one of the disconnected hoses, I'd drain a couple ounces now. Maybe it's as simple as disconnecting a hose at the compressor and spinning the pulley by hand(?)

Old 07-08-2018 | 07:31 PM
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Yup: You need to get some of the oil out of the system. Too much oil and the excess will coat the interior of the heat exchangers sufficiently to cause very poor A/C performance.
Old 07-08-2018 | 07:38 PM
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Thanks for all replies. I will go ahead and remove some of that oil.



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