wasp01amg

Background

2001 E-55 112000 miles

I bought this car in October 2014 with 103,000 miles and have all the service records. The AC system never required any service besides the cabin filters.

Last year, spring 2015 I had to add a small amount of R-134A so the system would cool properly.

This year, March 2016, the system did not cool properly. I noticed an oily substance on the top of the pan beneath the compressor and the rest pressure was 4 bar. I topped off the system and it cooled properly for a couple of days and leaked back down to 4 bar.

I verified that all sensors work and aux fans function properly.

I have a vacuum pump, gauge set and R-134a.

Plan

I plan to replace compressor, receiver/dryer/accumulator, expansion valve.

Question

Should I replace the condenser too, or just back flush it?

What are you thoughts.

I have conducted searches and read many threads but I still would like to get constructive feedback from knowledgable members.

kajtek1

I had factory compressor still performing very well on car with almost 300k miles, so those things do last, epecially considering that I drive in 3-digits temperatures good number of days every day and am experiencing 114F from time to time.
Sounds to me that you found the leak source, yet you want to do major replacement.
Something wrong with fixing the leak?
Then yes, if you replace compressor, replacing dryer, where all the dirt collects is highly recommended. Expansion valve might require cleaning, but no replacement necessary.

wasp01amg

The reason I ask about replacing te condenser too is that I read that some of them are not suitable for back flushing. I appreciate your feedback.

Junster

My 99 E320 had an AC issue and was blowing hot air two years ago. A normal recharge won't hold for long and repeated the same problem. It also accumulated oil residue in the engine compartment.

I took it to a local garage and he replaced the shredder valve(?) that you use to charge the system with on the low side for free. He said he remembered it was laying around somewhere in his shop. No problem since then. What a nice guy... You never know it could just be a simple thing.

So, I asked for an oil change from him on top of the basic system recharge he had to perform.

wasp01amg

I know of two schrader valves for the high and low side refridgerant connections. Is there a third one somewhere?

Plutoe

No

wasp01amg

Didn't think so.

kajtek1

Having high pressure sensor display on climatronic why would one worry about high pressure schrader valve?
I think you are overthinking the issue.
First you want to replace compressor where there is no indication anything is wrong with the old one.
Than you want to flush the system, while you are still using the same refrigerant?
Flush is needed when you convert the system from one refrigerant to other.

wasp01amg

I think you do not understand my origonal question. The compressor appears to be leaking. Loss of pressure, oil leaking out past the shaft seal. The parts kit I'm considering includes the compressor, expansion valve and receiver/drier. The warranty states that all these components and the condenser, if unable to flush, must be replaced. I can get all of the parts from Rockauto for $350 delivered. I have a 30# bottle of refridgerant, vacuum pump and gauge set.

kajtek1

I would not spend $350 on part + several hr of labor on "appears" not to mention that you never said about leak on compressor in your original post.
Compressors seals can be replaced, but I agree that this is not really DIY, but still double check it is compressor that leaks, not 25 cents oring on fitting.

Plutoe

You are correct this spammer knows nothing about MB AC systems

wasp01amg

Pluton,
Who is correct?

Plutoe

verb (used with object)
1. to set or make true, accurate, or right; remove the errors or faults from: The native guide corrected our pronunciation. The new glasses corrected his eyesight.


2. to point out or mark the errors in: The teacher corrected the examination papers.


3. to scold, rebuke, or punish in order to improve: Should parents correct their children in public?


4. to counteract the operation or effect of (something hurtful or undesirable): The medication will correct stomach acidity.


5. Mathematics, Physics. to alter or adjust so as to bring into accordance with a standard or with a required condition.

verb (used without object)
6. to make a correction or corrections.

7. (of stock prices) to reverse a trend, especially temporarily, as after a sharp advance or decline in previous trading sessions.

adjective
8. conforming to fact or truth; free from error; accurate: a correct answer.


9. in accordance with an acknowledged or accepted standard; proper: correct behavior.


10. characterized by or adhering to a liberal or progressive ideology on matters of ethnicity, religion, sexuality, ecology, etc.: Is it environmentally correct to buy a real Christmas tree? Most of the judges in this district have correct political views.


Origin of correct

What do you mean by correct---pick a number and I will advise!!

wasp01amg

I would like to know if you are calling me a spammer? That is why I ask "who" is correct.

Plutoe

No you are not the spammer----you own the car ---you have looked at the car---you know the car---you have diagnosed the car---you can fix the car

When it gets slow----we get allot of spammers\drifters\post getters from the misinformation site BW---be watchful!!

wasp01amg

I was able to raise the car up today and remove the lower panels. Turns out the oil leak is from the hose between the condenser and drier. Much less expensive repair. $65 for hose and drier.

What is the proper oil and quantity for the compressor ?

kajtek1

I see you met forum #1 troll & spammer.
Now back to business. You have no way to measure how much oil you lost, so you have to use your best judgement.
The oil makes huge stains from few drops, so it easy to overestimate.
I would put 50% of recommended amount. You should find "oil charge" with R134 (for easy application) on the shelf.
Is your drier having inspection glass on it?

wasp01amg

Can't tell from the picture if the drier has an inspection glass.

Parts will arrive n a few days.

I'll add a bit of oil to the system before startup.

Thanks for the info.

kajtek1

Parts???
You just said it just hose?
What exactly are you planning to replace?

wasp01amg

Hose and drier.

kajtek1

Those small details might be not worth mentioning for you, but they can make major difference in car repair.
Most of AC oil accumulate in drier, so since you are replacing it with defective hose, you need to add close to 100% of oil capacity.

wasp01amg

So, what is the oil capacity for this system?

kajtek1

It might be listed on label under the hood.
If not, you will have R134 listed there and find universal chart for oil addition.

Plutoe

Be watchful you have received much misinformation up to this point---the total refrig capacity is 1000 grams---

and if you replace the drier add 10cc of approved oil and if you change the suction line add 20cc and if you change the pressure line add 20cc.--that's it

forget about may pole comments to look here and there!!

fabbrisd1

With fresh compressor - "most" are pre-oiled + fresh/new drier + updated driver requires the updated hose = yes, from what I follow here you are good to go... except, I prefer to have a shop do a evac and fill, rather than straight fill from the tank.

My experience it's good to get all the old **** out with the evac - which also serves to test all connections are good..

For me, if the compressor is "precharged" or "pre-oiled" personally I don't add oil... but that's just me..