AC Condenser and Dryer Reciever

[jordan_sorabjee]

Hi All, I am having to swap out my AC expansion valve. In the process I am going to replace the dryer reciever and condenser. I'm not replacing the compressor or evaporator as they seem fine (and are expensive). I'm happy with the correct qty of R134 to put back in, what is not clear is if I have to add any PAG 46 oil back into the dryer or condenser. I can't find it in the service manual either.

When the system gets vacuumed out, I know an amount of oil comes out too, do I just get the AC guy to put the same amount back in or should there be a specific amount in the dryer and condenser?

This is for a 1996 prado with the dryer receiver separate from the condenser.

 

[Dave]

Recovering the refrigerant may remove some oil, and this qty should be noted. There are also industry standard qtys that are replaced when components are replaces. A decent ac guy will know theses. Its all a bit of a guess, but isnt super critical, just not way too much or too little.

 

[Shayne]

Get a mobile A/C engineer because thats all he does and so he has a reputation to uphold , in my experience garages that do it as a side line are clueless .

 

[jordan_sorabjee]

Unfortunately I'm based out in Kenya so I'm not sure there are any genuine experts. Thanks for the help though. I guess I could try and drain all the oil from the dryer and condenser and try to measure it and replace the same amount.

 

[Dave]

You’ll have trouble getting anything out of those two. I’ll look in my book tomorrow for the recommended amounts.

 

[Dave]

Unfortunately I'm based out in Kenya so I'm not sure there are any genuine experts. Thanks for the help though. I guess I could try and drain all the oil from the dryer and condenser and try to measure it and replace the same amount.

What is wrong witht the expansion valve?

 

[jordan_sorabjee]

Thanks Dave. Much appreciated. I did find it for the qty for the 80 series, but that wouldnt be any use other than a rough idea. Think it was 10ml for the dryer and 40ml for the condenser (which it says to be added back to the compressor) assume this can just be added back into the system via the regas machine.

So its either getting blocked or starting to fail. Ac works fine then suddenly doesn't. Not linked to outside temp. Thought it needed a re gas but when it took to the local AC guy, he showed me the pressure difference when he was doing it. Said the only possible cause was the expansion valve. He did say it wasn't a common issue.

 

[Dave]

Autodata says 30ml for the condensor and 12ml for the drier, plus of course what got removed with the gas. Yes the oil can be added by the machine, or you can put it in the components before fitting.

When the ac stops, is the compressor still turning, and what are the pressures when the ac stops and the compressor is still turning? Very rarely is the expansion valve at fault.

 

[jordan_sorabjee]

Awesome. Thank you.

Yes the compressor is definitely turning when it stops working. I can't remember the pressure but the guy said it was higher than it should be on the high side and lower than it should be on the low side. After he switch the car off it stayed pressurized which is why he said it was the valve. Do you suspect it might be something else?

 

[Dave]

I would suspect everything before the valve tbh, like freezing inside the drier. But normally if there is a blockage you will see a vacuum on one gauge. Also worth sucking everything out and weighing to check the correct weight as a starting po8nt.

 

[jordan_sorabjee]

So I made the error of leaving this job a little too late. My pump has packed in. Buying a new Chinese one this week. It says on the spec that oil fill volume is 200ml. I'm guessing this is just the oil that was put in for storage. I was always under the impression you need to drain this oil and fill with the correct volume. Anyone know what the correct volume is???

 

[Dave]

Yrs, you drain and refill with the same amount you got out the old one, plus maybe 20ml

 

[jordan_sorabjee]

Thanks Dave. Plan might be on hold, the new pump arrived today. Looks almost identical but on closer inspection the pulley on the new one is slightly smaller and pump is slightly bigger. When I measure the bolt holes there is a 5mm difference so it won't fit. Supplier says its the correct one...it obviously isn't...

 

[jordan_sorabjee]

Yrs, you drain and refill with the same amount you got out the old one, plus maybe 20ml

Just a thought. My old AC pump is seized so it either doesn't have any oil in it or can't be drained because I can't turn the pulley. In this case how would I know how much to put into the compressor or would I just leave it with the amount that was added. As I am going to replace the condenser and reciever I will be adding about 40ml and 20ml respectively to those. Would I just drain what is in the pump and add the same amount back minus the 60ml?

 

[Dave]

Just a thought. My old AC pump is seized so it either doesn't have any oil in it or can't be drained because I can't turn the pulley. In this case how would I know how much to put into the compressor or would I just leave it with the amount that was added. As I am going to replace the condenser and reciever I will be adding about 40ml and 20ml respectively to those. Would I just drain what is in the pump and add the same amount back minus the 60ml?

In which case it is recommended to flush the system and start from fresh. In reality, do as you say and add the oil for condenser and drier, and make a guess for the compressor. Some compressor come completely full of oil, which is way too much. Some come empty.

 

[jordan_sorabjee]

OK great. Thanks bud. I'll let you know how it goes