I am replacing a leaky evaporator on a 2013 Mini and plan on replacing the condeser, draining the lube from the compressor, flushing the whole system, and evacuating it for 30 minutes.

How much PAG lubricant does it take? The tag under the hood says it takes 1.01 lb of R134a but it doesn't mention lube levels.

Thanks,
Peter

 

My evaporator is also leaking. :( It will be a HUGE job to replace.

Does your refrigerant hood label show code 6 916 084 on the bottom right? If so, the metric R134a weight is incorrect. The image below shows the corrected version for the original hood label.

Are you replacing the original compressor because it also failed? If the compressor did not fail and no metal debris is found in the system, then flushing the system may not be required.

Your new compressor (OEM = internally-controlled Sanden SD6V12 variable displacement compressor) should come with instructions on how to calculate the amount of oil to add.

To ensure removal of all air and moisture from the repaired A/C system, you must monitor the system evacuation with a micron gauge (vacuum </= 500 microns after 10-minute vacuum decay test). Depending on your vacuum pump (cfm and 1 stage versus 2 stage), how you design your vacuum set up, and the amount of moisture and refrigerant trapped in old PAG, the vacuum process could take from an hour to overnight.

When you recharge the evacuated system with R134a, add some UV dye with refrigerant just in case the repaired A/C system has a leak.

 

A huge job to replace. Ha! And as I recall from doing it years ago, it is associated with large doses of profanity. I think you start by removing the rear bumper and keep removing things until the dash board is gone.

My hood label says 9 286 376 and reports that it is “1.01 +/- 0.02 lbs” of “only R134a”. According to a BMW note I have, that means PAG lubricant whereas R134YF uses Sanden lube. The note also describes how much lube to use but the description is the most confusing ever produced despite giving several examples of how to calculate it.

I don’t know how much oil I’ll lose from freon loss or from removing the old evaporator. I want to flush the oil out and put in new oil to get the oil level just right.

 

That should be correct.

The OEM compressor uses PAG 46 (SP-10) oil. If you know the specific compressor that you plan to purchase, contact the company to request the detailed instructions that come with compressor. If the instructions are unclear, ask the company for clarifications before you purchase.

Slowly recovering the old refrigerant from the low side will generally minimize oil loss.
If the A/C system is very low on refrigerant before recovery, most of the oil will abnormally accumulate in the evaporator, and the compressor will have very little oil. That's why running an A/C system low on refrigerant can cause compressor failure.

 

The Nissens compressor (sold by RockAuto) for my 2012 Mini lists an oil capacity of 130 ml.

 

I am sticking with the original compressor since it seems fine. I would have used the original condenser but it is slightly beat up from road salt and they are cheap.

I wonder how much PAG46 comes in a factory compressor?

 

120 ml?




135 ml?

 

Has anybody removed their A/C compressor? I am replacing my evaporator this Friday and will remove the compressor just to drain out the oil.

Any suggestions?

The evaporator project is already expected to be a monster job so I’m not expecting anything worse with the compressor.

Peter

 

I'm delaying (procrastinating) my evaporator job until winter to avoid the Houston summer heat and humidity.

Do you have the time or energy to document your dash tear down and removal of the Heating & A/C Housing with pictures in this thread?

 

Sounds like a good idea that I would have liked to see myself. BTW, I’m using the free manuals from NewTIS (BMW produced?) and have printed off about 70 procedures. That will include the condenser replacement and the removal of the compressor for oil draining.

Peter

 

Free manuals? Can you post the link?

I have put together an order of operations plan for evaporator removal by combining information from YouTube videos and the Bentley manual. YouTube videos on this topic are sparse, but the 2 or 3 that I found were much better than Bentley.

 

I can’t find it exactly but recall that NewTIS can give access to what looks like the complete factory manuals. I think it was some legal thing between them and BMW where it couldn’t just be posted online.

Try contacting them at http://newtis.info
And ask for access. They told me I had access with a special link and asked for a donation, which I gladly paid due to the super job their link has.

Peter

 

Thanks, Peter.

 

Btw, I’m in the middle of replacing the evaporator and the most difficult part so far has been how to release electrical connectors. I’ll try to get pictures of how each difficult one works.

Otherwise I’ve spent most of my time just removing things to get access to the next thing down below.

Peter

 

 

Before I put the how-to together, I thought I would mention something.

One thing that is SUPER important is to lay things out in order as you remove them. I ended up redoing the whole process a second time because of a bunch of left over fasteners and laid things out in two long rows so I knew what to reattached next. If you follow the NewTIS in reverse, you will be reattaching things out of order because several things are mentioned repeatedly. The first time, I must have bolted on and removed several items like the roof pillars and central gage cluster five times.

BTW, after printing everything out, I just used a iPad to guide me.

Peter

 

Even as careful as I was, I ended up with a dozen spare screws.

1. Lay each component as you remove it from the vehicle in an ordered collection. When you reassemble, only assemble it in the reverse direction of the part you laid out. If you do it in reverse order in the manual, you will have to take many parts off again and again. Only reattach them in the reverse order that you took them off.
2. 90% of the fasteners are T20 sheet metal screws and T30 machine screws. When you remove a part, if it uses a different fastener than those two common ones, even if the threads are just a little bigger (like when it might screw into plastic) or the washer flange face is a smaller diameter or it’s silver instead of black, then tape the special screws to the part to avoid a mix up later.
3. With only two exceptions all of the sheet metal screws go through apart and attach onto a sheet metal nut two exceptions are the top screw on the side vents. It goes through two parts and then screws into a sheet metal nut and the really complicated screws on the back of the speedometer they go through two parts and then down inside a plastic nut

 

Thank you for sharing!

 

Useful tools

1. 10 inch forceps for removing the plastic clips that hold the wheel rocker covers on.
2. Right angle pick and pry tool is really good in many places but required to release little electrical connectors

 

Yikes. Major update. The AC seems fine but everything is problematic.

I think the SZL unit in the steering column has failed. Another guy had this happen when he replaced his clutch.

I was hoping for a loose connector but everything pointed to the SZL.

1. Steering wheel only reads positive degrees rotation, Then it flakes out completely.
2. Related to that, stability control is out.
3. Turn signals don’t turn off when you straighten up.
4. Brake light is yellow on the dash.
5. Windshield wiper runs when you shut the engine off. (The control is on the SZL unit).
6. OBDII reads steering wheel angle even when engine is off and key out.

 

Yikes!

During removal of the steering column, you may not have properly secured the steering wheel clock spring, which allowed it to rotate from its original position. If this happens, you can break or damage the clock spring wires when the steering wheel is turned.

 

Right. I was careful but then read that you can also just rotate the dial fully both ways and then split the difference, so I did.

I think that might have been my mistake. I should have left it.

Although another guy had the same failure after doing a clutch job so maybe leaving the power off for a week is part of it???

 

If you did NOT exactly follow the instructions below or your front wheels were NOT pointed straight forward when the clock spring was re-installed on the steering column, then the most likely cause of your SZL-related problems is unfortunately a broken or damaged clock spring.

On the bright side, you seemed to mention that the A/C system is working after replacing the evaporator & condenser. Can you see where the evaporator was leaking? If so, do you have any pictures?

 

I did follow the instructions exactly; however, there is some rotational friction so it isn’t distinct when you reach the end of travel and maybe I overdid it. I thought I was careful about this.

The car had spent 10 years up north and suffers from salt corrosion and the evaporator did look corroded. Sadly, the evaporator didn’t show a leak. I used UV dyed freon and when I got it out, there wasn’t a distinct UV stain under a bright UV light. I didn’t see a UV stain anywhere on the car.

I did use a TIFF freon sniffer and it did register when I stuck its hose down the air vent so that is how I came to decide on the evaporator.

I took a hundred pictures and once everything is fixed, I’ll post the process.

I found a numbers matching SZL unit used online for $130 shipped and I should have it installed by next week.

Peter

 

Hmmm...sounds tricky.

I also used a refrigerant detector to identify my MINI's evaporator leak. The detector found a strong signal coming from the left side trim of the passenger footwell.

Fantastic!

​​​​​​​Sounds like a good price. Good luck with the fix!