Good show, John. That's the way to "fix" an A/C system!

 

Hey that is good information you found about the hose connection to the Expansion Valve
about the Cu seal being optional. When I took mine off there was no seal. Also did not
know the torque - just "mechanic tight" BTW, I do remember the tools I used were
a short handle mm wrench and an adjustable wrench on the valve. Its a bitch getting up
in there. I think I will remove the drivers seat next time.

And, thanks John for the E-brake fix, working great.

 

Well I'm out of excuses. all the parts I need to at least get everything complete under the dash are in.

The overtime has been paying for everything and this weekend I hope to have the last of the parts on order except for the compressor. Still researching which compressor to buy. I would like to find one serviced with POE oil but they seam to be unavailable.

 

Better hurry up and get that AC done, else cold weather will come and
all it will be good for is to defrost your windshield It was a beautiful
day today for top down driving - no AC was needed today.

 

OK I'm going in.

I'm a little behind schedule. I spent all day flushing out and taking out the radiator. But I had to get that out of the way.

http://www.benzworld.org/forums/r-c107-sl-slc-class/2446361-560sl-cooling-system-overhaul.html

Now on to the AC.

While doing the radiator I found the compressor was really making a bearing noise. Since the compressor was off it was obviously a clutch bearing and driving the car any further may have caused other problems.

I tried vacuuming the system to see if it would hold a vacuum at all no chance. I now have the vacuum on just my gages to make sure they are still working after all these years. First picture is after checking my system about 1/2 hr after bringing it to 27" hg. Second picture is the gages without the system. I also will need to check my R12 gages because that's what is going back in.

Time to go back out there and try out my shinny new 4 angle wrenches I got from Summit for $37.50.

 

Are you going to inject some dye into the system just in case you have a slow leak?
On my 380SL, it appeared to hold vacuum but the system had a small leak and would
no longer cool after 3 weeks. The Dye revealed the leak at the rear of my AC
Compressor and I had to replace the Compressor.

 

No dye. I have a good electronic leak detector if I can still find it.:laugh

 

So I didn't get as far as I would have liked. I got the expansion valve and lines out. I found I dident need my 4 way wrenches only because the flats were lined up just perfectly for my regular open ends.

Wrenches required are:

12mm and 17mm for pressure balance fitting.
14mm and 19mm for aftermarket high side line, 22mm for MB high side line .
17 and 22 for low side of expansion valve.
24mm and 27mm for low side line.

So its 12, 14, 17, 19, 22, mm wrenches involved in replacing the expansion valve. Add in 24mm and 27 mm to replace the low side line. A 32 mm wrench is also required under the hood to disconnect low side line from fuel cooler.

I also found that caps I purchased from Mcmaster contain the elusive coned copper washers that I cant find any where. I believe I will be using these washers.

Does anyone know a good way to get the clip back on for the expansion valve coil. I could not get that one off until I pulled the coil out of it.

My 40 year old R12 gages appear to be holding vacuum better than my 8 year old R134 gauges.

 

"I also found that caps I purchased from Mcmaster contain the elusive coned copper washers that I cant find any where. I believe I will be using these washers."

Is that the optional washer for the connection between the High Pressure Hose
and the Expansion Valve?

Also, are you going to replace the High Pressure hose? Mine split open and I
just used an aftermarket one off Ebay. Someone suggested I just have the old
hose assembly rebuilt with "non-barrier" rubber hose - but no shops around here
do rebuilds anymore.

 

Yes I will be replacing everything all hoses and everything in between except the evaporator and condenser.

I will be putting the cone shaped washer on both sides of the expansion valve.

 

So at this time I have a three day weekend and almost nothing to do. I can install the expansion valve and close up under the dash except I really don't want to until I test for leaks.

I will be flushing out the evaporator and condenser. I can run all the hoses but I don't have the seals yet.

Good news is I just placed the last order of parts. I decided to go with a Denso rebuilt compressor from AutohausAz at $300.00. A bit more than whats available on E-bay but it's from a trusted source.

So far this job's total cost is $756.90.

That includes replacement every part and tube in the AC system with the exception of the condenser, evaporator and controls.

I also found an interesting thing about the elusive expansion valve cone washers.

If you look at the EPC under 560SL there is no cone washers shown.

If you look in the EPC under 300SL there are 2 washers shown which happen to be the same washers used on the receiver drier.

Since these part numbers are the same as the receiver drier seals on the 560SL which I know to be flat, my guess is MB is expecting these washers to cone on installation. In any case I ordered these washers and we will see.

 

So at this time I have a three day weekend and almost nothing to do.

Good news is I just placed the last order of parts.

So far this job's total cost is $756.90.

That includes replacement every part and tube in the AC system with the exception of the condenser, evaporator and controls.

I also found an interesting thing about the elusive expansion valve cone washers.

If you look at the EPC under 560SL there is no cone washers shown.


Since these part numbers are the same as the receiver drier seals on the 560SL which I know to be flat....In any case I ordered these washers and we will see.

John, R U going to publish every item by part number in your refurbishment
Of your A/C overhaul....so us lazy farts can order everything before I start
On my 560sl A/C overhaul ......with this write up that you so thoroughly compliled, i can now do my car with confidence

 

Hmmm. My 560SL did not have a washer at all where the high pressure hose
connected to the Expansion Valve, but the other end of the high pressure hose
utilized a rubber washer where it connected to the Receiver/Drier.

 

There was no copper washer in this one but my 86 Samson had just one not sure which side. I understand it is a trick AC people use to stop leaks. Maybe its also required in Europe.

There are rubber washers at the RD end of the high pressure hose but the pressure sensors and switches use copper washers but I am not aware of 2 sizes. I have also seen rubber O rings installed by people in the flair fittings to stop leaks that seamed to work out although I cant attest to there longevity.

 

I thought today would be pretty simple. Remove a few parts and flush out the condenser and evaporator. But as usual a simple job turns into a catastrophe.

Got the condenser and RD out, no problem. Went to take out the compressor with the manifold line set installed. Found the mounting bolt between the two lines that mounts the muffler to the compressor bracket was frozen. Realizing this was a socket head and likely to strip I removed the power steering pump and bracket assembly. I cleaned out the head of the bolt with brake cleaner and compressed air and I was able to get an allen wrench on very securely with a pipe for leverage. Result was a bent allen wrench. I then took a huge CP 717 impact hammer with a blunt tip and shocked the side of the adapter plate in the bolt area. Then the bolt came right out. The CP717 is a little too large for this job but it did make short work of it with just two half squeeze bursts of the trigger. Put a little bit larger dent in the housing than I would have liked.

Because that one gave me so much trouble, I decided to remove the rest of them while I had the compressor out so I could reinstall with anti seize. Of course those ones came out with no trouble at all. I also found there was a secret bolt holding this adapter in place which had to be removed by lining up a notch on the crank pulley over the bolt hole.

I had to take a break to take my son to get his computer fixed. So for tonight I will go back out and clean the garage. With all these parts out its a good time to power wash the engine bay as well as the parts I removed.

So tomorrows task will be to power wash everything. Reinstall the compressor adapter plate and flush both condenser and evaporator. There really isn't much more I can do this weekend.

 

I hate to open a new can of worms but you are well into it . . .

http://www.benzworld.org/forums/r-c107-sl-slc-class/1905874-oil-seals.html#post8162146

Your last picture in post #18 looks really familiar.

 

I not going that far. Plan is to pull engine at 200K miles clean and reseal everything.

 

I don't know what happened to my pictures today. Just one came out of my initial evaporator flush. Evaporator was filthy. I bought 2 qts of Dura Flush (actually 25 oz in a 1 qt can. Took about 1 and 1/2 can to get the evaporator clean enough to see through the fluid coming out. I would like to run another 2 qt through but its $32 a qt. I also only got to put 1/2 can through the condenser. If I'm feeling rich tomorrow maybe I will pick up two more cans. Its expensive stuff but doing it over is alot worse.

Aside from that the car sits waiting for parts to come in. At least every thing is clean and ready to go back together.

 

It would be interesting seeing more photos of how you flushed that Evaporator.
I assume you did not remove the Evaporator but left it attached as you cleaned it.

BTW, what are the special properties of the flush fluid that makes it so expensive.
Wonder if there are less expensive fluids?

 

I had about 10 more pictures I took that did not come out for some reason. I will try to get more pictures of the setup. The evaporator was still in the car.

I don't know what makes it so expensive there are alternatives down in the $12 range. But I only see good recommendations for Duro Flush.

If you read the warning label its actually some scary stuff. If you open the can above 89° F you are supposed to chill it first. And of course if you inhale it, get it in your eyes or on your skin, bad things will happen.

By the warning labels it sounds like something that will actually work. I bet it no available in California.

 

OK so I thought there might be more parts and I was right. After seeing how the condenser flushed out I decided to replace it. It acted like it was clogged until the air pressure over came it. The new condenser is $331.20 from Autohausaz but I have too much time and money into this to take chances.

I'm not as concerned about the evaporator because every thing that passes through that had to make it first past a fine mesh screen and then an expansion valve. So the AC system will now be all new except for the evaporator and the fuel cooler.

I have done too many jobs where you replace the compressor and test it out. Results usually end up with outside air temp at 95° F and inside air outlet temps at ~85°F. In the old days it was easy to just dump the R12 install a new condenser and recharge. But today this my be the last 3 cans of R12 on the planet.

I also found a better way of doing the flushing. I just ordered a remote filter kit from Summit. I can install two 45° 1/4" flare to 1/2" pipe adapters for it and flush it through several time with recycled fluid before one last pass with fresh stuff. With I would have though of it earlier.

http://www.summitracing.com/parts/trd-1028

 

OK I took some pictures of the flushing tools.

I recommend you get a flushing tool like the one shown. They are about $35. I also recommend that you purchase some caps and fittings to make hooking it up to your AC components easier. I purchased a set of these fittings and caps from Mcmaster and as you can see the caps come with the elusive copper cone washers. But I will break it down to only the ones you need for this job.

To hook up the evaporator to the flush kit leave the low side line connected to the evaporator. The low side line is the fat ~ 2' line that goes to the fuel cooler. Disconnect that line from the cooler and that is where you will inject the cleaning solution. You will need to connect a hose to the other end of the evaporator for the cleaning fluid to be routed outside the car. I chose to use AC manifold lines so I needed to get an adapter to reduce the inlet of the evaporator to a 1/4" male flair. There is no such fitting so you need 2 fittings.

From Mcmaster Carr P/N's: 50635K433 and 50635K385 In the first picture I sent I have a yellow AC service manifold line connected to these two fittings. The yellow line gets routed to a drain pan which was shown in an earlier post. I was able to connect my yellow line right to these fittings but it was difficult. It would have been much easier if I had one of these 90° adapters which I have since ordered.

Super price on Robinair 40563A at ToolTopia.com

But don't go pumping in cleaning fluid just yet otherwise you will have a huge mess. You still need to plug the little port that goes to that pressure differential sensor on the expansion valve. You can just reconnect the expansion valve fitting to use it as a plug or you can purchase a 1/4" cap P/N 50635K542 from Mcmaster. Incidentally that 1/4" cap comes with a cone washer which is NOT called out as optional in the torquing specifications for the expansion valve and I did find one installed in this car. See my previous post with the torquing diagram for the expansion valve.

OK so with that port plugged off and the inlet to the evaporator routed to a pan outside the car you can now pump your cleaning solution into the evaporator through the low side hose. To use the flushing tool you put in about 1 to 2 pints into the canister and charge the canister to ~ 125 PSI. Its kind of scary because the light weight AL can heats up when you pressurize it and feels like its going to explode. You hold the gun tight to the hose and allow the fluid to flow into the evaporator and allow the pressure to bleed off to zero. It takes quite a while to bleed off and you really need to hold tight for a long time. Wait about 3 minutes for the stuff to work than blow the evaporator out with air. Because my regular compressed air nozzle is too small to seal in the low pressure line I had to use the tool with just an air charge several times to air flush it.

I wanted to really blow it out good so I cam up with an alternative. I removed the low pressure hose and capped the outlet with a 5/8" cap Mcmaster P/N 50635K546. Now I happened to have an adapter from my fuel injection tester that had a 1/4" female flair fitting on one end to connect to the pressure balance fitting on the evaporator outlet. It also had a male airline type connector that would connect right to my air hose. I could hook that up and flush with air for hours.

I don't know where you can get such a fitting but its easy to make with a short piece of 1/4 tube (brake line) and two flair nuts Mcmaster 50635K562. You will need to flare it but no need for a double flair for this application. You will also need another adapter Mcmaster P/N 50635K5433 and your standard 1/4" male air coupling to connect to your air hose. For most people in the US the airline coupling is Mcmaster 1077T17.

So that's about $21 in fittings from Mcmaster. 1 or 2 of those part numbers will be available locally and cheaper.

 

Bully BULLY! EGv107-worthy, I'd say...
...any seconds?

 

Thanks Ears

I cant second my own thread but I do have an update. I found the mother load of conical copper washers.

Gaskets, 45 Degree, Flared, Copper by Parker | Zoro.com

 

I just checked tracking and found my parts wont be be in this week so it will be a lost weekend.:frown

 

Wasn't that a movie?

 

Not much to report this week on the AC. I did one final flush on the evaporator and fluid was now coming out clear. I installed the expansion valve but did not tighten as I cannot install AC lines yet.

I will be holding this job up a bit to purchase some through the firewall hose grommets for the AC lines. I didn't purchase these before because its not clear in EPC which ones I need so I am now resorting to the shot gun approach of ordering them all.

One of these grommets is $45.00 so I hope that is one that I actually need. The rest of them are any where from $0.52 to $10.00.

Yes I am holding this up because I am being a perfectionist and that is why I could never make a dime in this business.

I consider this particular car as one that could be brought to concourse condition if desired to do so. So I try to make all repairs to that level. While these pass through grommets will not affect the function of the AC system they do contribute to under hood presentation and possibly cabin noise. A few dollars now while the lines are out greatly simplifies this process.

So as it stands right now it looks like I am on schedule for 9-27-15. Or for the rest of the world that would be 27-9-15. SO I will have my AC ready just in time for NC October top down cruising weather.:smile

 

SO I will have my AC ready just in time for NC October top down cruising weather.:smile

You ARE in aviation!

Air Canada always fixes the hanger heat in January and the shop A/C in July.

Thank God we treat aircrafts better than that.

 

My Compressor and Condenser as well as all the rest of the hoses and fluids I needed came in today.

Originally I was planning on using POE oil or Ester oil sometimes called the universal oil. I found this new stuff PAO oil that reports itself as the universal oil better than POE.

So there is PAG strictly R134a, POE for R134a/R12 and now PAO also for R134a/R12. According to BEHR PAO 68 is the preferred universal oil. They only recommend POE for hybrid vehicles using electric motor compressors. Read the attached article.

So I got the PAO 68 and against my better judgement I purchased it with the dye.

Behr 351214201 Refrigerant Oil

A note on seals:

I have been putting green HNBR seals in all my refrigeration lines and these used to be standard. I have found that when I ordered new seals from Mercedes I got 2 compressor seals for $17 and they were black. These seals were totally not required because when I got the compressor it came with black seals. The compressor is a re-manufactured Denso compatible with R134a. The liquid line I got from MB came with a seal for the connection at the RD it was purple. The BEHR after market RD came with green seals.

So my question is "Is Mercedes and Denso doing something new with a new compound of black and purple seal" or did they just say F it were not going to identify seals by color any more.

 

Just found another paper form the manufacturer on POA oils. Good read for the technically inclined.

PAOIL - The Refrigerant Oil Company

 

I'll 2nd for the EGv-107 inclusion. While reading this thread it was like roncallo was watching and documenting my AC trials and tribulations earlier this summer except mine was on an '83 380SL. I used the same flush system and fluid too. Although I ended up replacing the condenser and evaporator. And used an AC Delco compressor, 200 ml of PAG 100 oil, and Enviro-Safe refrigerant.

While doing the AC work I found the dreaded cracked heater box and removed the dash so I could repair it. Decided to go ahead and replace the evaporator, the vacuum actuators, and clean the heat exchanger while I was in there. I also replaced all heater hoses, the radiator hoses, the expansion tank hoses, and the transmission cooling hoses. Even the short 6 inch hose above the thermostat. Flushed the cooling system, pulled the block drain plugs, and put in fresh MB antifreeze.

Then, since the steering wheel was off, I decided to replace the steering coupler because there wasn't any rubber left on the old one.

While waiting for parts I pulled the blower motor to clean and lubricate it to try and fix the squeaky fan. The damn thing was so nasty I replaced the motor and squirrel cages. The blower motor box was in good shape after giving it a thorough cleaning. When reassembling I put on a new cover and gasket since the old cover had several cracks and the gasket was torn.

Well... Since I had the leaking power steering pump loose to replace the compressor I decided to pull it and rebuild it. Replaced both rear o-rings and the front seal. Pretty straight forward procedure documented in the EGv-107.

Then, while replacing AC hoses, I realized the main rubber fuel line from the hard line to the fuel distributor was enlarged to almost twice the normal size. It had expanded so bad the protective sleeve on the line couldn't be budged. So I replaced it and the 2 rubber return fuel hoses from the fuel distributor to the fuel cooler and fuel cooler to the hard line.

I'm guessing it's probably that fricking ethanol in the fuel that caused the fuel line expansion. I haven't even looked at the fuel line hoses back by the gas tank. I just started ordering all the parts to replace everything from the strainer, to the fuel pump, the filter, and all the lines. The tank is close to empty so I'm going to put a five gallon can and a funnel under the hose at the strainer and cut it so all the fuel, or as much as possible, can drain out before I crawl under there.

Sorry for the diatribe. I just wanted to 2nd the nomination for the EGv-107 inclusion.

Mark

 

I'll 2nd for the EGv-107 inclusion.

While doing the AC work I found the dreaded cracked heater box ....

Then, since the steering wheel was off, ....

While waiting for parts.....

Well... Since I had the leaking power steering pump loose....

Then, while replacing AC hoses,...

Sorry for the diatribe. I just wanted to 2nd the nomination for the EGv-107 inclusion.

Mark

Thanks Mark

Sounds like you have found how approaching a simple job on an old car turns into a time bomb.

 

O Rings

A good article on O ring colors:

Basically HNBR o rings can be any color.

http://www.santech.com/images/pdfs/TD030201.pdf

 

All parts came in yesterday. AC is being evacuated as we speak.

A couple of notes on the install:

Manual says the Denso compressor capacity is 120 cc and thats all it says.

For the earlier Frigidaire A6 compressor the manual is a little more detailed. It states the compressor capacity is 300cc and to use 300 cc if you completely flush the system as I did but to only put in 200 cc's if you just do a compressor change.

So the question is how do I handle a compressor change with and without a flush with a Denso compressor. Last time I did this I put in 6 oz 180 cc's based on recommendations from a seasoned MB tech. In servicing the system this year it appeared as if it was flooded with oil so this time I putting in 120cc's. I drianed the compressore and pulled out 120 cc of PAG oil and replaced it with 120cc's of PAO oil.

Prior to installing the compressor, I installed the new manifold onto the compressor. This alleviates the risk of getting crap in the lines when trying to fish them down and connect them to the compressor. When installing this compressor It is required to insert the four mounting bolts through the compressor mounting holes before lowering it into position. I lower the compressor and line assembly down into place and insert the forward manifold bolt loosely to hang the compressor in place. Then I start the four compressor mounting bolts and the aft manifold mounting bolt. All 6 bolts, 4 compressor and 2 manifold should be started before any of them are tightened. Make sure you don't have a belt tangled in behind the compressor mounting bolts.

I got to try out my new Eastwood digital torque wrench installing the manifold onto the compressor. This is a lot of torque wrench for the money. My old snap on will do the job but you need to look at the dial. Yes Snap-On did have optional lights and follower indicators available 40 years ago when I got this but they would have been an extra $500.00. This torque wrench has a real time display with lights and audio signaling and a peal torque mode, plus torque can be displayed in ft-lb, in-lb of N-m. 7 to 100 ft-Lb for $100.00. I got the torque wrench because I needed one this size to do all the AC line fittings and I really didn't have one in this size range. It turns out that you cant get to a single line with standard crows foot ends. To I ended up calibrating my arm before tightening.

On my first attempt to install the compressor and manifold assembly I found that I had to remove the assembly and elongate the aft manifold mount hole. I could have gotten it in but I did not want the system to have stress on it. There were several areas where I was not impressed with the fit of genuine MB formed tubing.

In any case got it all together and put the pump to it. Vacuum immediately pulled down to 30+ inches. Its been vacuuming for an hour now So I will go out and shut the gauges and see if it holds overnight.

 

Nothing but bad news

Went out to the shop and shut down the manifold gauges. Vacuum bled down to about 5" in about 15 min.

Thought I had some good news. I did a search for my leak detector and found it. But batteries were dead, leaked replaced batteries after trying to clean the corrosion. Dead as a door nail.

So this week I will try to purchase a Nitrogen bottle and start looking for leaks. I'm also going to need to get another leak detector. So it looks like another $300 took week. Maybe if I can use Argon I have a small bottle of that.:crying

 

Went out to the shop and shut down the manifold gauges. Vacuum bled down to about 5" in about 15 min.

Thought I had some good news. I did a search for my leak detector and found it. But batteries were dead, leaked replaced batteries after trying to clean the corrosion. Dead as a door nail.

So this week I will try to purchase a Nitrogen bottle and start looking for leaks. I'm also going to need to get another leak detector. So it looks like another $300 took week. Maybe if I can use Argon I have a small bottle of that.:crying

Leak Detection is something that should be of interest to all of us.
Do continue the detailing how you go about locating your leak.

 

If you pump in R134A Freon, would any residue have an effect when you
later pump in R12?

 

No but if I had PAG oil in with the 134a I would need to get that out. Im using PAO it does not mix with the Freon.