I have worked on a few cars with it, and I do not like it. It is NOT foolproof by any means and it does not give you the same temperature control as a properly working ACC II system....Robert

__________________
Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

I am considering it once I get my ACC system up to speed and something non-vacuum related craps out.

What is so different about it? I understand that some folks think it's some kind of silver bullet and I understand how you could have problems OUTSIDE the servo that it won't help.

The way it's jumped across the servo vacuum switch can't give the same amount of flap control as the stock system. I don't think...

Flap Control will henceforth be referred to as "Flappage" to simplify discourse...

__________________
My occupational hazard bein'
my occupation's just not around...
1980 300SD
1980 300SD

"Flappage" is still reasonably functional with the exception of the fresh-air door. The center vents, the defrost vents, and the foot vents all still work. I manually move my fresh air door - mostly open in the winter and mostly closed in the summer.

I agree - the UT kit is not a silver bullet as it does not correct pod issues, control panel issues, or vacuum leaks in any of the connectors. After my servo locked up and drained the battery it really was an easy decision to move to the kit.

Everyone is different and we all have our own ideas about how the car should work and how much we time and money we are willing to invest in our cars.

My local indy says that he has installed two UT servo kits. He says that they have upgraded the original unit and the newer one is much better.

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"Life is tough...it's even tougher if you're stupid." John Wayne


Dave
Pawleys Island, SC

'79 300CD

The ACC II system works exceptionally well, providing all the values are correct.

When I was working on these cars everyday, I saw very few bad servos.

Most of the problems I encountered were vacuum issues, bad solder joints in the amplifiers, bad temp wheel resistance values, rotted fresh air hose to the in car temp sensor and shorted A/C low pressure switch.

I have seen several cars that had new servos installed by other shops and the system still would not work.

Most shops still throw parts at the ACC II system and fail to follow the diagnostic protocol.

People come and ride in my W116 and marvel at the fact that everything works. It really is easy when the factory gives you all the specs and test procedures. If you test the circuits, you will quickly see what is not within specification.

Pods are also easily rebuilt if you don't want to replace them. I will often collect a box of them from Pik-N-Pull when I find a car that has been stripped down. I test them and set them aside for later use. Seems like someone is always stopping by and needing a good pod.

All the pods in my car are original and still work.

I did A/C work everyday on these cars, mostly the W116 and R107's with the ACC II and I never had one that I couldn't quickly figure out what was wrong by following the oracle.

I used to pull the servos apart and replace the shaft seal and reseal the bottom half where the coolant circulates. I forget now what seals I substituted, but it was from a transmission overhaul kit.

The servo unit is relatively easy to calibrate following the technical data I have posted.

For those that want to use the Unwired Tools Digital Kit, I say why not??? If you have the money, then there is no reason not too. However, they are not 100% trouble free as they would have you believe.

Most times, I find a 107 or 116 in the junkyard with the aluminum servo and they work perfectly, because the ACC II system failed as the result of another component failure in the system.

#1 customer complaint on the ACC II was #3 and #9 fuse failure, which in 90% of the cases was a shorted A/C low pressure switch.

#2 most common customer complaint was the system switching from hot to cold, which was a rotted in-car temp sensor hose.

#3 most common customer complaint was the A/C switching to full heat when the temp wheel was moved. Most common cause was a 'dead spot' in the wheel's resistance curve.

In all the years I worked on these, I can think of only 5 servos that I replaced to get them working correctly.

Hope this post helps....Robert

__________________
Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

Hey Doc, I assume the only "calibration" of the servo itself is changing the position of the feedback pot to insure the controller is "seeing" the proper position of the servo motor?

Some servo stuff I found helpful:

http://www.seattlerobotics.org/guide/servos.html

Dig deep with a big shovel...

__________________
My occupational hazard bein'
my occupation's just not around...
1980 300SD
1980 300SD

There isn't much to it, but it is important. The oracle I posted explains the procedure.

__________________
Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

The oracle is old and fuzzy, and I don't see very well. I even tried printing and couldn't read it

__________________
My occupational hazard bein'
my occupation's just not around...
1980 300SD
1980 300SD

E-Mail me via my profile. Send me a big envelope and I will mail the oracle to thee....

__________________
Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

So I have no heat coming out at all, Even in defrost with a warm car. So I tested the servo according to the manual, and it opens and closes OK. It does whine at a set interval when opening and closing but it stops quickly. Thinking it must be the aux pump, I tried to test it by powering it directly from the battery. I couldn't hear anything click or the motor go when powering it directly. Am I doing this right? Is the aux pump bad?

Thanks.

Jason

Mine will begin to get warm at idle with the aux. pump off but it works a lot better when the pump is running. I'd remove and try to lube/free up the aux pump and test it. I would also make sure that your servo is actually opening the water valve. You can remove the crossover chamber at the bottom and check it visually.

I can post some pics if it'll help you.

Lot of good info that will explain what should happen when and at what setting here:

http://handbook.w116.org/Climate/83-600.pdf

__________________
My occupational hazard bein'
my occupation's just not around...
1980 300SD
1980 300SD

It be-ith true. The servo gods exist. Thou partake-ith on the path to enlightment doth ancient texts and thou will find thee.

All I did is read the manual 3x and run a few tests on the servo and "cast thou holy alcohol on thou terminals" and I now have heat.

I'm feeling the need to keep studying the service manual or the god's will be pissed.

Thanks.

Keep after it. My wife uses my 1978 300SD often for her Mary Kay business. She is a tough customer. The ACC II system works very, very well IF all the required values are within specification.

I am using one of the dreaded 'Mantis' servos (bought new in 2005) that have such a bad reputation, but it works better than any other servo I have used, once properly claibrated.

__________________
Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

I downloaded each page as a jpeg image and printed them off. Still a bit fuzzy but at least they print out as 8.5 x 11. They printed out as 2/3 page images, right off the site.

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Mac
2002 e320 4matic estate│1985 300d│1980 300td
Previous: 1979 & 1982 & 1983 300sd │ 1982 240d

“Let's take a drive into the middle of nowhere with a packet of Marlboro lights and talk about our lives.” ― Joseph Heller, Catch-22

That would apply to every MBz independent around here for sure.

Ok now you're frightening me. What's a pod? The thingies labelled as "vacuum element" in the diagram?

Or is this entire thread code for some DEA sting operation? ("...someone is always stopping by and needing a good pod.")

__________________


Mac
2002 e320 4matic estate│1985 300d│1980 300td
Previous: 1979 & 1982 & 1983 300sd │ 1982 240d

“Let's take a drive into the middle of nowhere with a packet of Marlboro lights and talk about our lives.” ― Joseph Heller, Catch-22