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A/C Parts Order Help

2K views 22 replies 5 participants last post by  schicksal 
#1 ·
I'm getting ready to order parts for my upcoming a/c rebuild and want to make sure I get the right parts, in the right quantity, ordered the first time.

The compressor currently installed isn't even complete, so that's on the shopping list. BUT what brand? I see Denso and Four Seasons advertised. Which is better?

The center dash vents don't work, but they do stay closed pretty tight. That means as a minimum I have one vacuum pod that doesn't work. These seem to be about $90 online... or I could get a bunch of rebuild kits from Performance Analysis and just do them all? I've seen it mentioned in a few threads, but how difficult is it? A Mighty Vac is also on the shopping list btw.

I'd like to find a new temperature control dial since mine is worn looking. Are these available anywhere?

I'm also ordering a drier, belt, and an orifice tube. The a/c static tests at about 10psi (obviously very, very low), but with the compressor showing clear signs of problems I'm going to replace old components, put on new o-rings and see if it'll hold vacuum for an hour before looking at other items. Hoses show no signs of trouble.

So my shopping list is...
- Compressor (make TBD)
- a/c belt
- drier
- orifice tube
- belt

- vacuum pod rebuild kits?
- temperature control dial?

Other stuff:
- gasket for the power antenna
- Speedometer gear
- capacitors for the clock
- misc. light bulbs (gear selector, light switch, a/c switch?)
- take off dash cap, make a hole for the temperature sensor

Am I leaving anything out? There will be plenty of a/c rebuild pics in exchange for advice. :)
 
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#3 ·
That's a good one... I haven't so much as even looked at the a/c belt tensioner roller.

All my 134a stuff has leak detector dye in it, and I have a black light to make it glow.

Any idea on the compressor type? I see mixed reviews for both the OEM brand and Four Seasons. Also, I'd really like to buy a new temperature control dial but can't find anyone selling just that part...?
 
#8 · (Edited)
I think the mono valve works... the only reason is because when I put it on defrost the air that comes out the defrost vent is HOT. It'll be another 4 months before this place cools down enough to test beyond that.

I haven't really been able to fully test the climate control or switching units so far because it's so hot over here, and the a/c part of the system is completely shot. Add to it, the fact that I don't have the manual and am not entirely sure how it works. I know that...
- the fan and automatic buttons work great. Fan speed increases with the system detecting higher temperatures in the car.
- off works
- economy works
- black up/white down = ??? nothing changes
- white up and down = ??? nothing changes
- defrost works
- recirculate apparently works - the red light takes a second to come on

Since I can't get air to come out of anywhere but the dash vent I have at least two pods out now (the relaxed state of the floor vents is closed), a problem upstream with the line in or whatever/wherever Y34 is in the diagram isn't working.


.


^ MB p/n 124 821 29 67
COOL! I searched to no end but wasn't using the right words. I thought it was bonded to the wheel.
 
#7 ·
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The compressor currently installed isn't even complete, so that's on the shopping list. BUT what brand? I see Denso and Four Seasons advertised. Which is better?


The compressor on your car was manufactured and supplied to MB by Denso. I don't know that Denso remanufactures for the replacement market. Four Seasons is a major distributor of auto AC parts, new and remanufactured.
 
#10 · (Edited)
edit: found the vacuum distributor and traced the lines back upstream to the tee ont he driver's side of the car. The vacuum line from the engine to the tee is missing. There are no loose vacuum lines in the area, or any that I can find at all in the engine compartment. Any idea on where the heck this thing originates? Nothing is clearly missing...

Might not need to order vacuum pods after all.
 
#11 ·
Thanks - I've been searching here high and low even to find a picture of what the actual vacuum switch looks like. Is it something mounted separately from the pushbutton control? It almost seems easier to pull the glove box and have a look at where the lines go, if they don't disappear too quickly.

It seems right now as though it's behaving as if every pod is in its relaxed state. Massive pod failure is one possibility, but so is a failure of the line going to the vacuum switch or the switch itself...
they disappear very quickly. The vacuum switch is directly behind the glove box and a bit to the left. There are only 4 lines going out of it and one going in. It has numbers on it 1 thru four, except one is not on the end, it's the second from the right.

1988 mercedes 560sl: vacuum leak in climat control system..factory - JustAnswer

Where did you find vacuum pod rebuild kits? Those puppies are spendy.
 
#12 ·
See the Dash removal thread:

http://www.benzworld.org/forums/r-c107-sl-slc-class/1658034-dash-removal-84-380sl.html

You will need to remove the dash to replace pods in the center. I prefere replacing 3 new pods in the center because I dont like the thought of 25 year old plastic in a $2000.00 location.

The 4 outer pods can always be replaced resonably easy without removing the dash, so I would rebuild those.

Check the pods to see that they hold vacume, if they do then check the heater box to see that the part where the center vent pod mounts is not cracked. If pods are OK and no crackes there is no reasone to pull the dash.

There is no orifice tube in a 560SL. It uses an expansion vlave. If replaceing the expansion valve flush out lines and evaporator after removing old expansion valve. Then install new expansion valve with a new sealing ring and screen. The valve the sealing ring and screen are all purchased seperatly.

Replace any seals with grean R134 compatible seals. Remove all oil from compresser and service the compressor and rest of system with Ester oil so you can now choose if you want to continue using R12 or R134. Service system with R134 first and verify no leaks prior to vacuming out and reservicing with R12.

You will also need a new hose that goes fron the sensor to the heater box. You can either purchase on for about $50 or make something for ~$2.

If you buy an evergrean compressore it will be a Denso overhauled by Evergreen.

Good Luck
 
#16 ·
To check the mono valve, use multi meter to test the connection for juice, when in A/C mode, you should have juice. If not, then there is a problem with your control unit. If it has juice, but hot water is still flowing to the heater core, it is shot. You can feel feel up under neath a bit or past the mono valve to see. I'd be surprised it it was still working.
 
#19 ·
Here are four pictures of both areas - where the line to the a/c pods is unplugged and where I think you're talking about where it should come from. It's hard to get a clear shot of the tee at the back of the engine because of all the throttle stuff in the way.

The blue/white line coming from the tee at the back of the firewall seems to be plugged into something... I didn't want to really pull on it too hard, because perhaps it's going to a transmission controller? I'm still not entirely sure I'm looking in the right place for where the a/c line should originate? The gray line (also seen at the tee, and where it passes through the firewall) I'm assuming runs to the fuel economy meter.
 

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#20 ·
I followed the white/blue vacuum line from its tee on the intake manifold and it really should be going down to the transmission. It plugs into a red thing down there.

At this point I'm at a loss... if anybody with a 560 knows where on the intake the a/c should plug into that'd be great. Especially if its location can be explained relative to the bung I already found that runs to the transmission and economy gage.

I swear things are harder when parts are missing than when they're present but broken...
 
#21 ·
The first pic is of the vacuum feed at the rear of engine--the line is white or clear. Looks whiteish to me. THe second pic is of the junction at the driver's side firewall. The white/clear line continues on into the firewall, the other point goes to that yellow thing-a-ma-gigee where it splits into to red lines.
 

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#23 · (Edited)
THANKS!!! I bought a 5/32 tee and used some vacuum line that I already had, and...

Vents behave the same way as before. It feels like the quantity of air coming through the defroster has gone up at least. Recirculate activates faster, and I can hear a faint hiss if I listen closely when I hit the button. I bought a MityVac 8000 this evening and will get to work with the pods on an individual basis.

So the shopping list looks like...
Whichever mainstream supplier
- Compressor (either Denso or 4 Seasons... whoever has fewer complaints when I do one last search)
- a/c belt
- drier
- expansion valve, the sealing ring and screen
- belt
- gasket for the power antenna
- gasket around driver's side door handle
- belt tensioner / pulley, pending inspection

Ebay/dealer:
- temperature control decal

Performance Analysis
- vacuum pod rebuild kits

odometergears.com
- Odometer gear

Someplace local:
- capacitors for the clock
- misc. light bulbs as needed
- hose from temperature sensor to heater box

I'll start another thread with the actual repair work on it, so anyone in the future who's looking for actual a/c rebuild advice rather than what to order might find the solution to their problem.
 
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