I've seen just as many bypasses as I have functional evil servos with the ACII system. Its a Chrysler designed farce that does not belong under the hood in the first place, IMO.

That was a newly rebuilt servo that I bought, and paid a bunch of money for it. Maybe you can contact them to see if they'll send another?

...or in 30 minutes you can put in a nifty little manual valve that only the biggest Mercedes nuts will notice, most of them will completely understand why.

By installing a bypass valve you loose the systems original function.

I had my servo replaced about 6-7 years ago with a alum body unit, it has worked great ever since. When all is well its a good functioning system.

I don't mind bypassing the system temporarily, but I do want the car to have it's original functionality. If the servo system in it right now fails again, I will go with a digital servo. Basically I want Norm to be operational like it was in 1980.

I'm sort of slowly "rebuilding" Norm, and would like to sort out everything like it should be. If all that is left is for me to try a different servo and it works, then awesome that's what I'll do.

Jimmy is sending me his to test out. If that fails then I will rig up a bypass until I am able to have my servo rebuilt or until I can purchase a digital servo.

ATTA BOY !
 

That's the right attitude .

Never give up , never say die .

:D

By some miracle I got the servo rebuilder to send another one, only requiring a core deposit. Considering I ordered the part 18 months ago that's pretty impressive on their part. I left Colin a lengthy message.

Anything for good ol' Norm. :thumbsup2:

Wow that was very nice of them. Was it George Murphy, I know he sells rebuilt units.

Well Jimmy's aluminum servo came in today, and I plugged it in to see what would happen...

...it started to hum instantly :D Looks like I have a working servo on my hands! I will be installing it completely tomorrow and hope for the best. Looks like I might have working AC by tomorrow!

Congrats!!! keep us posted.

New (used) Klima I Servo
 

On the odd chance it runs the battery dead when the car is shut off , I spliced a cube relay into the # 30 (power) circuit behind the glovebox , next to the amplifier .

When the key is off , no power goes to the amplifier so it cannot ruin the servo trying to park it nor fry the amp's circuit board .

Problem solved .

I hope you'll consider running R-12 as it's the very best there is , 65 F in Death Valley when it's 125 F outside , car fully loaded down , no worries .

Remember to lube the auxiliary electric water pump on the bracket next to the servo too , it needs annual lubricaion to avoid failing & frying the amplifier .

^I already recharged the system with R134, I really didn't want to hunt down R-12. The system does blow nice and cold before the car warms up after sitting overnight, I don't think it will be a problem at all to be honest. If anything I can just clear out everything in the future and fill with R-12, but I'm happy with 134.

I'll oil that aux pump tomorrow. It's only about a year old, so it's probably due for a change.

If the battery dies overnight I'll definitely try that.

I'm pretty excited to see if this all finally works out.

It WILL WORK !
 

Once you take the time & effort to go through all the little fiddly bits ,it works gangbusters and you'll be cool in summer and warm in winter .

I am extremely happy to know that that thing worked. I almost blew off pulling if from the Euro gasser W123, but I just couldn't resist when I saw the aluminum body. And man that car was clean!
I couldn't help myself though. I of course polished it before I sent it. It is a compulsion....... :o:o

It really isn't that complicated, just expensive. Really it's only three parts in the ACCII system that can go wrong, as long as your compressor components are in good order. If this works I'll be rather happy.

Well I'm glad you didn't! It looks a lot better then the plastic bodied servo, that's for sure. I noticed it looked a little shiny, now all I have to do is polish the top of my air cleaner and all will be well =]

Thanks a ton Jimmy, I really appreciate it!

How Little You Know !
 

I should write up all the things I had to replace or repair to get mine working ,it was simply amazing .

FWIW ,it's not ACCII ! Chrysler called it Air Temp II and Mercedes called it
Klima I .

Success!! After swapping out the servos this morning and warming the car up I am happy to report that the entire system works! AC blows really really cold, I'm quite happy with it, and heat comes on nice and hot as well.

Finally after more then a year the system is working!

Ka'plah!!!!

:thumbsup2:

Awesome, just in time, its getting warm here in Jax.

Yeah it's hot as balls here in Orlando, pretty much fixed it on the first day of warm weather.

After driving around a bit I noticed a few things. When the car is sitting at idle (stoplight, etc) it gets really hot (the car temp that is, not the cabin temp). Like at the 100* line, usually it sits around 90* at all times and doesn't go higher unless I park it. When parked it goes past the 100* line, obviously not good! This is with the AC compressor on.

My condenser fan does not come on at all. I'm guessing the high temps are a result of it not coming on. I'll rig up some power to it shortly to see if it works, otherwise I might need a new one.

The cabin cools down in about 5 minutes. The 134 is really really cold to be honest, I'm happy with it.

I'm going to try a few different amps as it seems I have to "trick" the servo to blow hot air. But it's not a big deal at the moment.

Otherwise I'm incredibly happy that this system finally works!

Its going to rise up a bit when you're idling on hot days. Anything under 110* is okay. The aux cooling fan should be kicking on if it gets much higher than that.

Are you sure your fan clutch is working properly? I'd think the car shouldn't overheat at idle if the pusher fan was dead, but that the AC would just blow warmer.

My car's temp is rock solid at idle with the AC on and a new belt fan / clutch, but I also have dual pusher fans...

-J

Its not necessarily overheating... I've owned half a dozen of these cars and they all did the same thing. If it goes above 110* then something's not right.

Fair enough. Still worth checking the fan clutch... though it seems like the ones on the 617 fail a lot less frequently then the 603.

-J

The fan and fan clutch work fine. It spins normally with the engine, no problem there. It puts out a lot of wind! I was just wondering if the aux fan was supposed to come on or not.

If normal operation is 110*ish then it's operating normally.
I'll try to push it a little and see if it'll go higher, but I don't think it will. My coolant was topped off today as well, so that's not a problem either.

The aux fan should come on based on refrigerant temp, not coolant temp. One of the two switches on the receiver dryer triggers it.. I believe it is the one with the wires coming right out of it, not the one with the spade connectors. EDIT: see below.

After taking this photo I started Norm, half way leveled off, and drove 20 minutes. I'd guess it was a mid 70s day....:D If it was going to overheat, this would have done it. I suppose that was a while ago, though.

http://i251.photobucket.com/albums/g...0/IMG_0083.jpg

Sitting in the car now and the aux fan came on. All is right in the world :)

The aux fan is triggered by the Refrigerant Temperature Sensor, which screws into the drier and has two wires and spade connectors attached. The other sensor attached to the drier is the Hi/Low switch, which breaks the circuit when refrigerant pressures get too high (or low).

You don't have to discharge the system to change the temp. sensor, as it just threads into the drier housing. The pressure switch with the oring and two spade connectors sticking out is the one that needs discharging to change out.

I broke the temperature sensor while redoing my A/C two years ago. While I waited for a new one, I jumped the aux fan connections so the fan was always on in city driving. :o

Congrats on the working Evil Climate Control™!

Thanks for the correction on the temp switch... that's good to know.

-Jason

GOOD NEWS !
 

It's good it's working , this picture is killing me with jealously ! my TD will never look that nice .

Time to dig this thread up again, but don't worry everything is working fine :D

Well when I rebuilt the system I used 134 to recharge it, mostly because I didn't want to spend a ton of money on R12 and then discover a leak in the system I didn't know about. Well the 134 works, but not very well. It really isn't all that cold during warm days (like 60 out the vents).

Now that I know my system works fine, I want to put R12 in it (or freeze12, envirosafe, whatever) but am not sure how exactly I'd go about this. I know I would have to replace the dryer, but would I have to replace the expansion valve as well? Also would I have to flush the system and compressor again, or would just replacing the dryer and expansion valve, vaccing the system, and charging work?

Essentially my question is what to I do to convert back to R12 from R134?

Headache
 

You goofed ~ this is why you evacuate the system then let it sit a few hours with vacuum ,to see if it has a slow leak .

To change it back to R-12 , you must needs open the sysem again and flush it completely , replace the reciever-dryer & oil but *not* the expansion valve then you must needs evacuate it and test again before putting R-12 in .

If it gives you 60° F at the vents now , that's as good as it'll ever get , leave it alone .

I didn't goof, I wasn't even sure that doing all of this was going to bring my system back to working order. It also ended up needing a replacement servo to see that the system operated properly.

It can get better then 60*, and honestly that isn't a whole lot of work to do so I'll go ahead and do it.

You Goofed
 

No way 'round that .

I also went down this particular road ,prolly much further than you did as I had to replace not only the Evil Klima I Servo and it's amplifier but also the auxiliary water pump , the entire vacuum hose harness from Servo to under the dashboard , electrical harness bits , the heater pipe matrix along the right side , freeze plugs , water nipples on the engine and on and on.....

If you fix it , it will work . simple as that . no need to ' test ' by using a refrigerant you don't like . the servo doesn't affect the refrigerant in any case .

When the car was new the AC didn't cool below 60° F so I'm not sure why you think it should or can do so now .

The rule of thumb in AC is : 30° F drop in temperature between outside and inside vent temp .

My Klima I HVAC will provide 65° F outlet temp. in Death Valley when it's 120° F outside for what that's worth .

I hope you knew what you were talking about because I'm a little lost.
Colin didn't have a leak, he just isn't happy with his freon choice......
R12 will give you the very best Colin. Freeze12 a close second from my experience. Envirosafe another level down, then R134a way down at the bottom.

^Thank you Jimmy, this is what I was going for. And after seeing your picture of 42* out the vents I believe I can reach those temps with R12.

http://i29.photobucket.com/albums/c2...h/Smash303.jpg

Im sorry but Colin can get better than 60F out the vents, prolly not with R134 though. I use enviro-safe freon in both of my cars. My W115 can put out 30 degrees at the center vents while moving, on a 80 degree day. However my W123 can't really get much colder than 45F out the center vents.

He Said :
 

' I used R-134a because I was worried it'd have a leak ' ~ that's why he goofed as one needs to re-open the system to change the typ of coolant , negating any leak test done with the R134a coolant .

You cannot have 30° out the AC vents as the evaporator core will ice up before that .

Each to their own I guess .

I'm still learning about this R134a stuff , it needs a slightly different operating pressure to reach maximum efficiency ~ the " Walking Tree Of Knowledge " @ the shop knows how to tweak an early , R-12 designed system to work as best it can with R134a but I still prefer R-12 in my own cars .

I hope all here know that it is *imperative* to run the AC for at least 5 minutes each week to maintain the system as the oil circulates within the coolant charge .

As always , my advice is free and worth almost 1/2 that .

Please stop insulting me and telling me that I goofed. Yes I was afraid I would discover some sort of leak, the system had nothing in it before I did all the work. Read this thread, I'm sure you would realize I had no idea what I was doing. I spent a lot of time and money in an effort to repair this system and was not sure if I had done it properly. I'm 19, I'm not a master mechanic and I'm doing the work on my own because I enjoy doing it.

I filled it with 134 because I had 3 cans laying around. I wasn't about to spend 100+ dollars on R12 only to find out that I did something wrong.

Yes I vacuumed the system, yes I replaced all the o-rings, and yes it held pressure, but no I was NOT confident in my work on the system at the time.

Give me a break, stop telling me that I "goofed" because I didn't. I merely was unsure of my work and didn't want to spend a ton of money on R12 if it didn't work when I had three free cans of 134 sitting in my garage. I had planned on using R12 if the system held up, and that's what I want to do.

Now all I wanted was an answer to my question, which is what I got. Please stop telling me that I goofed, I assure you I knew what I was doing when I put 134 in.

Colon -
First of all congrats on the efforts! You've stuck with it and probably have more experience in working on these "older" systems than many younger "master" mechanics that'll never see them due to the age of the cars. You've done the right thing.

And for many of us who are just starting out diagnosing our A/C systems, you've provided somewhat of a path to follow. Wish there was a definitive step by step to troubleshooting these systems...I've not been able to find it here, just cobbling together many threads to make sense of it all.

Let us all know how Norm likes the R-12 when you get to it.

Colin :
 

WHOA ! ~

I didn't insult you .

You have done a masterful job here and I thought that was obvious .

I applaud your dedication to this job and following it through to the end and sharing your travails so others can learn too .

You done real good here , don't be so touchy .

I make mistakes too and I post 'em up so others don't follow in my footsteps .

This is called learning and I'm still learning after all these years .

I *think* that you , like I , have this older Mercedes as an actual car to be used and enjoyed , not as a hobby car ~ that's a good thing and you'll learn much when working on older machinery , especially when you encounter DPO & DPM bodge jobs .

Really , I didn't mean to insult you , you made a basic mistake and that's it . nothing to be upset about .

Sourcing Cheap R-12 Freon
 

FWIW ;

it is still out there , you just need to be *very* careful about mentioning it when you're searching for it .

It's a fairly serious crime to sell it so most folks who have it, won't admit it when anyone else is within earshot .

I paid $20 per shortie can last time .

I know a guy who has a 150 # cannister of it he says is for sale but he won't give me a price ~ this is frustrating to the extreme .

Once in a while I see the shortie cans at yard sales for $1.00 each....

You've gotta beat the bushes when you want a thing .

What type of oil did you use? If it was PAG you can blow out most of it, leaving the drier alone, then add ester oil. Ester is compatible with mineral, PAG, & parafin and is also compatible with both R12 & R134a. If you used ester oil you're good to go, just evac & recharge with R12. Mineral oil is only compatible with R12 & hopefully you didn't use it with the R134a, unless you only used the ac for a short time to test it, then no harm will be done (they don't mix causing a lack of lubrication if run too long). If you did use mineral oil, just evac & recharge with R12.
When you remove the R134a, do it slowly. If it comes out too fast it causes turbulence in the drier which can rupture the desiccant bag. If that happens, it will clog up the expansion valve next time you use the a/c.

:D never gets old...

R12 is going to help but you're never going to be completely comfortable during a Florida summer. When it got over 90 degrees around here I wouldn't drive R12 equipped Ol' Turbo because the AC couldn't keep up. Even the AC master Jimmy during the hot Texas summer months retreats to his Ford truck.

My wagon came from Sedona Arizona, and had a very dark tint on all the rear windows, and a slight tint on the front two. With a reflective screen in the windshield the car barely heats up above outside temperature. All the windows on wagons makes it a rolling greenhouse, which the AC even with R12 will never successfully overcome. This was even an issue with my mighty 2004 E500 wagon. The cabin would get so hot even with excellent ac and ventilated seats it took a very long time for the cabin to reach a comfortable temperature.

I was getting low 40 degrees out of the vents using r134 last summer. Its definitely possible.

It's alright, don't worry about it. It was just a little frustrating to see someone say that I messed up after all the time I put in to it. I'm over it though, no harm no foul.

And really, thank you for the help you've given me in this thread.

I'm fairly positive that I used ester oil, because I remember seeing PAG oil and not wanting to use it. Also I believe that the bottle said "for R12 and R134 systems". I have the bottle sitting in my garage somewhere, so I'll go verify that. It's good to know that I could just evac and then recharge the system with R12 with that type of oil.

I have wondered if tinting my windows would help, but never really had the ambition to do it. I know that it would be a ton of fun getting those rear cabin windows tinted! I might actually try this should I not be comfortable with the R12, I'm sure Norm wouldn't mind.

I took this picture today outside temp was about 82 degrees, car was moving.

http://i42.photobucket.com/albums/e3...Picture531.jpg

Window Tinting
 

I went through this some years back and it turns out the the best UV blocking
isn't the dark tint ~ research the 3M tint films and you'll find a very good UV (heat) blocking film that's not terribly dark so not only can you see out , the cops won't be hassling you either .

Most folks automatically buy the darkest & cheapest film so they look cool (or stupid) then think that tinting doesn't help so much when it does , if you do it right .

I'm flabbergasted to see that 30° C dash vent temp . very cool indeed .

I have a bottle of Ester AC oil , I *think* it says R12 & R-134a compatible .

It's a PIA to keep track of how much total oil you put in , too much and the system loses efficiency , too little and the weeny Delco R-4 compressor grenades on a hot day...

As long as it's cool(ish) and dry in the car , I'm happy .

Time to revive this thread.

I placed an order for a brand new compressor/drier/expansion valve. I'm going to be using R12 this time should I be able to find it. Tinting is also in the works.

Let the battle for cold air continue!