The old compressor in the 83 300D was giving a high pitch squealing noise when it was on. So I bought a re-manufactured unit from eBay and installed it myself. I don't know who designed the R4! I tried to put 8 oz of ester oil in but it all drained out during installation. What a waste of time and money. Anyway, I changed out the recv/drier, charged 8oz of ester oil which comes in a pressured can then 3x12oz can of R134. Everything work as expected and now I have A/C.

However, the 'new' reman compressor is quite noisy to my liking. I called the seller and he asked me to send it back and he will replace it. What shall I do?

1) I have no R134 recovery machine so I have to vent it to the atmosphere.
2) R&R the compressor again is not something I would like to do.
3) The compressor is noisy and I do not know how long it will last.
4) It is going to cost me $20 shipping, 3 cans of R134, 8oz of ester oil. Probably $70 total. Assuming I keep the recv/drier which is new.

What would be your recommendation? Leave it the way it is?

__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

When you say noisy, how noisy is it? Is it embarrassing noisy or just mildly irritating?

__________________
Codifex
1981 240D ChinaBlue (Got her running with a donor engine.)
1983 300DTurbo w/sunroof.
1984 300TD manual sunroof. (Electrical Gremlins)

It is difficult to describe noise on paper. I can only compare it with the compressors in the 190D or 300SDL. They sound quiet, i.e. you do not know it is running unless you look at it. With the R4, I know it is running from 10' away. You can tell something is not running quite right.

__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

It sounds like the system is over filled with oil.
Here are the correct volumes.
R4 compressor A/C system OIL charge Per WIS: 83-520


.

__________________
ASE Master Mechanic
asemastermechanic@juno.com

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
1984 190D
2003 Volvo V70
2002 Honda Civic

https://www.boldegoist.com/

+1 Roy, 8oz is the total system capacity of oil in that car, so if all you did was change the compressor, and the dryer, you are 6oz overcharged with oil.
you will now need a flush kit in addition to the refrigerant, new dryer and oil to get this car cooling properly.
if it's not been run much, you may not have damaged the compressor with all the extra oil. STOP RUNNING IT NOW!
get a flush kit, and some dry gas to blow it all out with. CO2 is a good cheap choice, but any bottled gas will do EXCEPT OXYGEN!!! DO NOT USE COMPRESSED OXYGEN!@!!!!
get all the lines and coils blown out. you should also replace the expansion valve, but it's not critical, if you remove it and clean it well.

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

As long as you have to do that much work, you may as well go back to R12. It's easier on the compressor as a bargain.

The R4 should be running PAG150. It requires a higher viscosity oil.

I think the reman unit is the culprit. The issue is whether it is worth my effort to redo all the work. There is no guarantee that a 'new' reman unit will be any quieter. What is the downside if I leave it the way it is? I am leaning towards to do it again when it craps out.

I do not think there is any issue using ester oil instead of pag oil.

__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

I recommend you go with a NEW unit, and go back to R12. That's what I did with my 83 240D (Which has less HP than the 300D) and the A/C works very well. Quiet, cool, even at 95 degrees at 1 mile elevation. Dare I say it - the 240D hardly notices when it is on. You can tell when it kicks in, but it's NOT a huge drag. My R4 reman unit lasted less than a month before it died.

* Get a new R4 compressor
* Figure out the correct sealing washers for it
* Vacuum out all the R134a, it's not as good (IMHO) as R12, purge the system thoroughly.
* Change the fittings back to R12
* May have to change the drier and receiver, etc. (I'm no expert in these things)
* Reassemble, charge with R12.
* Enjoy cool and quiet A/C

__________________
83 240D - 4 speed manual - Manilla Beige
189K miles, Tachometer mod, cool wooden shift knob from PeachParts, CocoMats, Original factory paint, manual windows, manual sunroof. Starting to add AudioWrap to this car too!

You could always go the way of ROLLGUY or the Klima conversion kit and convert over to a Sanden type compressor. No more R4 headaches.

__________________
Cruise Control not working? Send me PM or email (jamesdean59@gmail.com). I might be able to help out.
Check here for compatibility, diagnostics, and availability!

(4/11/2020: Hi Everyone! I am still taking orders and replying to emails/PMs/etc, I appreciate your patience in these crazy times. Stay safe and healthy!)


82 300SD 145k
89 420SEL 210k
89 560SEL 118k
90 300SE 262k RIP 5/25/2010
90 560SEL 154k
91 300D 2.5 Turbo. 241k
93 190E 3.0 235k
93 300E 195k

Like P-E, I have a 240D 1983 also, VStech and I did exactly this procedure (except mine has never seen R134a).

More hints from our adventure:
Get a new CompressorWorx R4 from a major chain auto parts store. (Tried to use PP but they could not match the price, you will quickly figure it out when you search online for R4 Compressor.) They will do a ship-to-store next day deal.
Got the package deal with the receiver dryer, compressor, and TXV. Go ahead and get the new temp and pressure switches for the dryer too, my old pressure switch did not easily transplant and the temp switch fell apart as I was trying to transplant it. Pick up an o-ring kit if you don't have one already.

Pull the lower passenger dash cover panel, and change out the TXV, it really isn't that difficult if you have the right line wrenches. Change all 4 o-rings. Bonus points if you service the blower while you are in there.

VStech, help me remember the correct oiling procedure, I know we put a portion of the oil in the compressor and the rest in the dryer, correct? How did we keep from losing the oil while installing the compressor?

If you have 2 people it really helps to get the compressor in place, if one holds it from above and the other goes underneath to put the bolts in. Front of car needs to be up on ramps for best results.

Once you get the compressor up in place then carefully remove the dust caps and hook up the manifold. Make sure you use the correct spacer rings that come in the box for the manifold connections.

Once you have it back together, vacuum, then pressure test with dry gas. If it holds the pressure, then vacuum again, and recharge with genuine R12. Only R12. No substitutes.

I can honestly say, on R12, it cools better than either of my newer Hondas with R134a. And we have probably one of the worst environments for AC here in the Carolinas, high 90s ambient and 90% humidity not uncommon in the summer.

And like P-E, I can barely tell when the compressor hits. I can hear it engage, and there is a momentary dip in idle, but then it is silent after that. And I have more cold air than I can stand. Most of the time the temperature dial is halfway between OFF and MAX, and the blower on speed 1 or 2. Even on scorching hot days.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

OK

Have fun swapping those R4s.

This.

I gave up on the R4, even a new Compressor Works one as I could not sort those stepped ports. I have never seen an R4 that was not noisy to some extent.

My Klima kit has been installed for about month now and was a breeze to install. Other kit seems to be popular too.

Just think of all the TIME you have wasted thus far with that R4 and still do not have a working solution...not to mention some cash. Refrigerant, oil, to the autostore and back, etc

__________________
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

What about those stepped ports? I am ready to install my compressor.

__________________
1984 300SD Orient Red/ Palomino
1989 560SEC
2016 Mazda 6 6 speed manual
1995 Ford F-150 reg cab 4.9 5speed manual

I had an aftermarket manifold hose which I think had something to do with it as the flange was not fully square. I looked and looked, could not find a good used one and sure as hell was not going to buy an OE one.

That is why I threw in the towel with the R4.

__________________
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]