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  #76  
Old 02-28-2010, 08:40 PM
79Mercy's Avatar
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Location: Florida
Posts: 4,128
Does the low side hose get cold?

So you get hot air or just outside air? The servo valve could be stuck on heat. Turn the key to position # 2 and turn the temp wheel all the way from 85 to 65 or 85 to 65 and get out and listen very closely for the servo changing settings. If you hear nothing tap the servo with your hand.
__________________
1985 300TD Turbo Euro-wagon
1979 280CE 225,200 miles
1985 300D Turbo 264,000 miles
1976 240D 190,000 miles
1979 300TD 220,000

GONE but not forgotten
1976 300D 195,300 miles
1983 300D Turbo 175,000 miles

http://i42.photobucket.com/albums/e3...e485-1-2-1.jpg
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  #77  
Old 02-28-2010, 08:47 PM
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^Yes, it is cold now. It wasn't before. Also still no aux fan coming on which is weird.

I'll have someone help me do that, but I'm pretty sure that the servo is stuck or my temperature dial is dead. Apparently that happens enough that there are rebuild kits out there for them.

I'll attack it tomorrow.
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  #78  
Old 02-28-2010, 09:20 PM
79Mercy's Avatar
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After you turn the temp dial the servo valve will groan for about 15 seconds.

I have been lucky my servo really hasn't given me much trouble at all, other than when it started leaking coolant about 7 years ago.
__________________
1985 300TD Turbo Euro-wagon
1979 280CE 225,200 miles
1985 300D Turbo 264,000 miles
1976 240D 190,000 miles
1979 300TD 220,000

GONE but not forgotten
1976 300D 195,300 miles
1983 300D Turbo 175,000 miles

http://i42.photobucket.com/albums/e3...e485-1-2-1.jpg
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  #79  
Old 02-28-2010, 09:29 PM
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Posts: 1,269
Lucky. Mine makes zero noise. What pins could I hook it up to to see if it actually works? This is a rebuilt servo too. I really think the problem lies in the CCU though.

Here are some photos.


Pulling vacuum.


Yep, that here is an empty and dry system. Yehaw.


After sitting for 45 minutes, the system held it's vacuum. That means no leaks, woohoo.


Here is what I replaced. The expansion valve...


The dryer...


And the compressor (under the hoses). As you can see it was hard to take a photo of, imagine how fun it was to actually remove and replace the thing.

Glad I got it out of the way though, it needed to be done. CCU install in the morning.
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  #80  
Old 02-28-2010, 09:52 PM
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Im doing this off memory but i think its correct. Use a multimeter on pins 1 and 7 of the AMP, you should see about 5 volts when you turn the temp dial. If you see voltage then you know your amp is good and that your CCU is good and the problem is a stuck servo.
__________________
1985 300TD Turbo Euro-wagon
1979 280CE 225,200 miles
1985 300D Turbo 264,000 miles
1976 240D 190,000 miles
1979 300TD 220,000

GONE but not forgotten
1976 300D 195,300 miles
1983 300D Turbo 175,000 miles

http://i42.photobucket.com/albums/e3...e485-1-2-1.jpg
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  #81  
Old 02-28-2010, 09:57 PM
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Join Date: May 2004
Location: Sunnyvale, Texas (DFW)
Posts: 9,673
Colin,
If it gets to the point where you think it is Dr. Evil Servo

let me know before you order and pay for a digital servo. I have an aluminum bodied servo pigeon-holed in the garage that I grabbed at PNP a while back. It isn't tested but it came from a clean euro W123 gasser. It isn't cracked of course so I imagine it is fine.
We will get Norm working somehow. Sounds like you have the AC side under control, you just need the servo to shutoff the hot water.... {or the CCU to tell it to shut off the hot water}
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Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John
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  #82  
Old 02-28-2010, 10:21 PM
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^Thanks Jimmy, I will for sure let you know.

^^I'll try that in the morning before I tear in to anything major. Do you by any chance know which ports on the servo itself are used to jump it? Like if I wanted to connect power to see if it will turn out of the park position, what pins would I connect it to?

Note I did not install the servo myself, but probably am able to now.
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  #83  
Old 02-28-2010, 10:30 PM
79Mercy's Avatar
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I don't know off hand which pins on the servo you can use to test it. I'll look....
__________________
1985 300TD Turbo Euro-wagon
1979 280CE 225,200 miles
1985 300D Turbo 264,000 miles
1976 240D 190,000 miles
1979 300TD 220,000

GONE but not forgotten
1976 300D 195,300 miles
1983 300D Turbo 175,000 miles

http://i42.photobucket.com/albums/e3...e485-1-2-1.jpg
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  #84  
Old 02-28-2010, 10:39 PM
vwnate1's Avatar
Diesel Dandy
 
Join Date: Nov 2005
Location: Sunny So. Cal. !
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Post Auxiliary Fan

it doesn't come on hadly ever , only when it's seriusly hot out and you're running the AC on MAX for a while , even then it should cycle off again after it cools the condensor down .
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-Nate
1982 240D creampuff 370,000 miles
1978 300CD back from the dead&1980 300CD ~ SOLD
1984 300CD KEEPER ! 430,XXX miles
1984 Euro 300TD Fully optioned SWMBO's
1974 350SLC 4 speed stickshift SOLD & missed
Krazy Kommie Ural Motos (3)
BMW Moto R60/6 Barn Find, 8,000miles
1959 VW #113 Deuxe Beetle, 36hp engine, stock
Junk, Rust, Arthritis, Crushed Spine,Broken Neck&Back
Memories &Peace Of Mind
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  #85  
Old 02-28-2010, 10:53 PM
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Heres a few tests for you:

The terminals are numbered left to right (1-10) as you face the connectors.

Connect +5 volts to terminal 4 and negative to pin terminal 5. You should hear the servo hum. When it stops it is in the "hot" position. (5 volts is best as that is what a properly working amplifier supplies and you don't want to fry it. I have used a small 9v battery in a pinch)

You can test resistance With a VOM on pins 1 & 2, resistance should be 200-250ohms.

To check the amplifier, connect a voltmeter between pins 1 and 7. With the ignition switch in the on position, the voltage should be about a volt. Move the temperature wheel from cold to hot. The voltage should increase to about 5 volts, and when the servo finds it home, the
voltage will drop back to about a volt. If it does not vary, then the amp is bad.
__________________
1985 300TD Turbo Euro-wagon
1979 280CE 225,200 miles
1985 300D Turbo 264,000 miles
1976 240D 190,000 miles
1979 300TD 220,000

GONE but not forgotten
1976 300D 195,300 miles
1983 300D Turbo 175,000 miles

http://i42.photobucket.com/albums/e3...e485-1-2-1.jpg
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  #86  
Old 02-28-2010, 11:19 PM
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Location: Orlando, FL
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^Awesome, thank you so much Stuart. I'll give that a shot in the morning with all the amps that I have in my possession!

God I love ACCII
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  #87  
Old 03-01-2010, 11:45 AM
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Location: Orlando, FL
Posts: 1,269
Alright Jimmy, might need that servo =[

I'm gonna run to Autozoo to return my vacuum pump, I'll post a detailed reply when I get back.
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  #88  
Old 03-01-2010, 12:31 PM
vwnate1's Avatar
Diesel Dandy
 
Join Date: Nov 2005
Location: Sunny So. Cal. !
Posts: 4,058
Post Servo Testing

Take your time , unplug it and do a comprehensive servo test including the use of your Ohmmeter as it has two different travels , one side is heat , the other is cooling and the fan speed wiper contact has two different sets of resistance too .

it is critical that the servo motor travels smoothly (i's quiet but you can hear it) and stops with a 'thump' ~ not slowly tapering to a stop in one direction of travel or the other , this is a common fault and it will cause the amplifier to fry .

There's a bunch of gears , wipers and a threaded screw , all must be 'timed' JUST SO " or it'll (maybe) pass a bench test but foul up on the car .

As the servo is ever so cleverly located in the lowest part of the cooling system , it acts as a sediment trap and the sediment will cause the valves gates to drag or stop and this is when the Bakelite body cracks or the motor's
drive gears strip, etc.

FWIW , ALL auxilliary water pumps have a little white plastic cap on one end you're suppoosed to gently pry out once a year (regardless of use) and drop one or two drops of engine oil in as it is running , this prevents them from siezing up and frying the amplifier (Klima I) or the CCU (Klima II) .

I hope this helps , working methodically and slowly , carefully , will result in ICE COLD AC , just try my old 1980 300CD W/ Klima I
__________________
-Nate
1982 240D creampuff 370,000 miles
1978 300CD back from the dead&1980 300CD ~ SOLD
1984 300CD KEEPER ! 430,XXX miles
1984 Euro 300TD Fully optioned SWMBO's
1974 350SLC 4 speed stickshift SOLD & missed
Krazy Kommie Ural Motos (3)
BMW Moto R60/6 Barn Find, 8,000miles
1959 VW #113 Deuxe Beetle, 36hp engine, stock
Junk, Rust, Arthritis, Crushed Spine,Broken Neck&Back
Memories &Peace Of Mind
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  #89  
Old 03-01-2010, 01:13 PM
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Quote:
Originally Posted by vwnate1 View Post
Take your time , unplug it and do a comprehensive servo test including the use of your Ohmmeter as it has two different travels , one side is heat , the other is cooling and the fan speed wiper contact has two different sets of resistance too .

it is critical that the servo motor travels smoothly (i's quiet but you can hear it) and stops with a 'thump' ~ not slowly tapering to a stop in one direction of travel or the other , this is a common fault and it will cause the amplifier to fry .

There's a bunch of gears , wipers and a threaded screw , all must be 'timed' JUST SO " or it'll (maybe) pass a bench test but foul up on the car .

As the servo is ever so cleverly located in the lowest part of the cooling system , it acts as a sediment trap and the sediment will cause the valves gates to drag or stop and this is when the Bakelite body cracks or the motor's
drive gears strip, etc.

FWIW , ALL auxilliary water pumps have a little white plastic cap on one end you're suppoosed to gently pry out once a year (regardless of use) and drop one or two drops of engine oil in as it is running , this prevents them from siezing up and frying the amplifier (Klima I) or the CCU (Klima II) .

I hope this helps , working methodically and slowly , carefully , will result in ICE COLD AC , just try my old 1980 300CD W/ Klima I
The problem that I am having is that the servo is not moving at all. In fact I don't think it is getting any power.

I put my voltage meter on all three of my amps handy, and all of them read the same voltage regardless of where I put the wheel. In fact they all read less then a volt.

I tried connecting power to the servo and got nothing. However it was rather awkward to get wires to the pins, so I'm not totally ruling out the servo just yet.

So here is what I am pointing to right now from all of this: The Servo might okay, but needs to be tested outside of the car. The CCU possibly is not sending the proper signal to the amp and thus nothing is happening. And the amp is dead, all three of them.

I think I'm going to slowly repair the system like I did with the AC components. I'll start with the amp and CCU, then move on to the servo. I don't want to pull the servo until I absolutely have to. Who knows, my amps might just be the problem and my CCU is fine.

vwnate you said you sold amps that actually work correct? I'd be interested in one if it does.
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  #90  
Old 03-01-2010, 02:05 PM
vwnate1's Avatar
Diesel Dandy
 
Join Date: Nov 2005
Location: Sunny So. Cal. !
Posts: 4,058
Exclamation Klima I Testing

STOP ! the Evil Servo
(LOVE that picture BTW) is easily tested in the car , it's easiest if you source the electric plugs from a junker but you can also make up some test leads with crimped on ends .

DO NOT even *think* of taking anything apart further than you need to , this is how you'll wind up chasing your tail forever

You can use battery voltage to run the servo back and forth , remember : it must stop moving with a thunk sound , not slowly load down until it stops moving ! .

I'm in the middle of a serious shytestorm @ work but I will write you a how to test in due time if you need it , it's pretty simple , IIRC George has a nifty booklet he'll snailmail you for free .

yes , I have good used amps but don't buy one until you _know_ the servo is 100 % O.K. ! .
__________________
-Nate
1982 240D creampuff 370,000 miles
1978 300CD back from the dead&1980 300CD ~ SOLD
1984 300CD KEEPER ! 430,XXX miles
1984 Euro 300TD Fully optioned SWMBO's
1974 350SLC 4 speed stickshift SOLD & missed
Krazy Kommie Ural Motos (3)
BMW Moto R60/6 Barn Find, 8,000miles
1959 VW #113 Deuxe Beetle, 36hp engine, stock
Junk, Rust, Arthritis, Crushed Spine,Broken Neck&Back
Memories &Peace Of Mind
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