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Heater Box Broken Vacuum Port

puchak

Grat Lover
Member
Going through my dash and I found a broken vaccum line that runs to the heater box.

What does this vaccum line do? Looks like I will need a new connector, unsure of P/N if anyone can help me out.

closeup-vaccum.png
 
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Uh-oh. That's a male-to-male fitting that connects to the center vent pod. There's a rubber hose on the inside which connects to the pod.

Part number is 000-805-00-03 but it went NLA over ten years ago. You'll need to cobble up a patch.

:runexe:
 
Based on your photo, it slides into the hole from the INSIDE of the heater box, and is retained by the round metal locking clip. You have to pull the dash and remove the top of the heater box to access this stuff... at which point you might as well also replace/rebuild all the vacuum pods while you're in there.

:yayo:
 
I already have the lower dash taken off, and was planning on taking the upper dash off as well to make sure there are no more surprises. So that could work, I can probably create some elegant homemade fitting to cure the connector woes. What is the function of this vaccum anyway?

As for the pods... Are the Klima rebuild kits good? I saw Gerry mention them here, but I'm unsure if I'm looking at the right thing.
 
I already have the lower dash taken off, and was planning on taking the upper dash off as well to make sure there are no more surprises. So that could work, I can probably create some elegant homemade fitting to cure the connector woes.
Cool - replace the 4 pods that require pulling the dash (center vent, 2 main air flap/recirc, and diverter if you can still get one).


What is the function of this vaccum anyway?
Assuming you mean the function of the plastic piece that broke, it allows a rubber hose to fit on either side. No need to pass through a tube or hose.



As for the pods... Are the Klima rebuild kits good? I saw Gerry mention them here, but I'm unsure if I'm looking at the right thing.
I believe the Klima kits are primarily for the 126 chassis - not sure if those kits work with the 124 pods. The Murphy/PP ACD-2010 diaphragm will rebuild the center vent pod 100%. The ACD-2010 kit will rebuild half of the pink dual-chamber pods, and ~90% of the time, that's all you need (the other half is usually fine). The diverter pod is NLA and there are NO repair kits available, it's smaller diameter. This one is usually ok, so you can leave it alone if you can't find a NOS diverter pod.

:banana1:
 
I know that the vaccum goes through, lmao! :rofl:

What does that vaccum specifically DO? You know, it being broken - what am I losing? Just asking from a pure curiosity standpoint.
OH! Sorry, I thought you knew... that is for the center vent pod. No vacuum means the center vent never opens, you do not get cool air out the center vents in cooling mode. The center vent pod is NOT fun to access or replace. Search the forum for details on repair & replacement.



Jokes and curiosity aside, looks like I need to reach out to PAC. Just 3 diaphrams given the diverter pod situation?
Yup... make it 4 diaphragms if you want to do the defroster flap pod while you're in there. The defrost pod can be access through the glovebox / passenger airbag opening, but it's way easier with the dash off.

:jelmerian:
 
Oh, that explains the cold air in the middle. Oddly enough, my W202 suffers (benefits?) from this as well... thought it was a Mercedes-Benz thing. LOL.

Okay thanks! I will reach out to them, should make for a fun little job.
 
The default safety action when the center vent fails, is to send air up the defrost so in the summer, you get cold air fogging the front glass. Normally, just a pod issue, failure would be weak flow out the center vents (not even effective) because of this defrost safety default. There are so many while you are there issues and refreshing all the rubber bits and pods perhaps even checking the condition of the heater core, condenser etc. You do not want to do this again obviously. I had done this on the 126 and they are pretty much the same.
 
The beast that is removing the dash, has been slain.

One of upper A-pillar plastic clips broke, it was so tight I couldn't get the plastic off the clip. I'll take that I guess, beats breaking anything else!

What are some things I should check for and observe? What are signs of failing items, in the heater core or condenser.

Does the top of the heater box come off to reach the inside? I would like to scavenge that connector to glue it back together.

the-beast-core.jpg
 
Nice work! Yes, the top of the heater box comes off, but it's not fun (screws/clips on the back side). Search this forum and PeachParts for more info on this job, plus more photos.
 
Pods arrived yesterday, going to deep dive tomorrow and post pictures of before and afters as well as any troubles I experience.

Off topic for HVAC, but how critical is the top clip of the A-pillar? Those who have removed A-pillars, if yours broke - what did you do?

Edit: Driver side is missing the metal bracket/clip (1249883378) and finding a replacement is over the moon in pricing.
 
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How on Earth do you get this pod out? I read through some of the documentation on here and elsewhere, the holes are so small I can get like 3 fingers in there.
 

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How on Earth do you get this pod out? I read through some of the documentation on here and elsewhere, the holes are so small I can get like 3 fingers in there.
It's NOT fun. 😟 But, it's possible.

Read the old threads on this forum and FruitBird (Pelican/PeachParts). I think I removed the flap/door to make room to stuff four fingers in there?

:sawzall:
 
FML. I picked up that you can remove the flap, I took the clips off of the box to give it some space to move and I see the pins to the door, but I’m not sure how to approach them.

3/5 pods are out otherwise, just need to figure this one out…
 
IIRC the flap bends quite a bit to allow removal. Look at the photos on my website in the "W124_dash" directory.
 
I’m looking at this but I don’t get it. I’ve got the flap all the way down. Can’t wiggle the door either way, is the photo from an earlier/later heater box?

The door in the photo looks like it’s made of rubber, mine is aluminum or something.
 

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Those photos are from an early 124, and yes the late 124 is slightly different. However, I've done the job on a late 124 and was able to get the pod in & out... but I don't think I have photos from the late 124. Last time I did this was probably 10 years ago!

:oldster:
 
Hmm. Do you recall pulling the door off then?

I know it’s been a while but I really have no clue how to tackle this, that door ain’t moving and the little pod pop removal switch is inconveniently under the door when extended.

Edit: I think I figured it out, hang on…
 
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Yep, so bending the right plate gives access to the popping pin… then you can push it out with a screw driver, once that is loose, you can unwind it with a bigger screw driver.

I will share this in Gerry’s pod thread so people can see it in the future.

Edit: Flat head not screw driver. Will update any pod troubles I experience.
 
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I started rebuilding one of the pods, replaced everything inside for trial even though it was probably fine. Jobs not hard, only lost half a clip and it still holds strong.

The travel distance of the vacuum seems a lot shorter, or is this just the case for one of the pods?

I have the same pod used in this video, with the long arm.
 
Are you rebuilding any dual-chamber "pink" pods, with the ACD-2020 kit? If so... yes, the travel is about HALF. See photos here.

This is why I do NOT recommend using those kits. 99% of the time the large-lift portion is fine, and you can just replace the small-lift diaphragm to fix them (this is the part which fails first).

:duck:
 
Oh my god, it literally is half, that’s what I thought! I figured it would have been a good replacement to do. I cut up pretty much a perfect rubber piece.

What the hell is the point of the replacement if it literally only works half way? Now I’m going to have half vent control???
 
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Oh my god, it literally is half, that’s what I thought! I figured it would have been a good replacement to do. I cut up pretty much a perfect rubber piece.

What the hell is the point of the replacement if it literally only works half way? Now I’m going to have half vent control???
I never did test "on the car" to verify how much this affects movement of the flaps. However I suspect it will not allow the flaps to move through the normal range of travel. And, this is why I've been dissing those -2020 kits ever since I figured this out many years ago! 😖

Worst case you can get another good used pod and only replace the outer diaphragm, which 99% of the time will fix the failure.

:wormhole:
 
If I got this pod, I can just interchange the springs and arms and it should work good as new?
Yup! All the "pink" pods on the 124 are interchangeable, if you swap the metal arms. In some cases you miiiight need to re-clock the pod to get the vacuum ports in the correct position relative to the mounting bracket. But the pod itself is identical.

I didn't realize AHAZ had any of these left, I thought they were long OOS / NLA. If you buy new ones, install them on the main air flap (recirculation) up by the firewall, since they require pulling the dash. You can put a used / repaired pod in the defroster location since that one can be accessed via the glove box / passenger airbag opening, without pulling the dash.

:jono:
 
Looks like there is a small amount in stock at various vendors (FCP, AHAZ, RME). RME shows 8 in stock. eEuroparts has the lowest price.

Check all the other part numbers for the "pink pods" to see if another is available for less!

:yahoo:
 
Dash is already out homie! This was going to be part of putting it back together, lol.

There is also this one in Indonesia for like $50 and at least a week of wait.

I’ll check the part number in a bit, lifting some weights currently.
 
Dash is already out homie! This was going to be part of putting it back together, lol.

There is also this one in Indonesia for like $50 and at least a week of wait.
I was thinking as a cost savings, put the new ones where they're hard to access... and a good used one where you can easily swap it in the future. If it's in the budget, all new is always preferred!

:spend:
 
The eBay one is missing the metal arm, which is fishy for a supposedly NOS part. And, there is no box / bag / label. Makes me suspicious it's a used pod that someone wrote a part number one.

:scratchchin: :stickpoke:
 
There is some difference in the pink pods. The ones by the firewall have less travel and weaker spring.
Ah, interesting... I did not know that. I have a new one of each on the shelf somewhere, I'll try to measure the travel.

It would be very odd that Behr would have different spring tension though. Not sure about that.

:scratchchin:
 
True, the arm should be there. Very odd, but there isn’t much else on the table besides spending double on reconfiguring a different part.

I had two different pods open and the springs were different, by the way. One had more coils.
 
I had two different pods open and the springs were different, by the way. One had more coils.
Great info - thanks for confirming! I wonder if one of the flaps requires more pressure to close?

:detective:
 
I picked up an aftermarket center vent that I plan to repurpose parts of into my old center vent. Very inexpensive at $55 shipped and the quality is pretty good!

Luckily the original bezel is some sort of lightweight metal meaning I can keep that to preserve the original look, only concern with this aftermarket vent is the wheel looks much cheaper than the original. Everything else looks good.

I'll post some pictures on Wednesday comparing the two, it may be possible to keep the original cosmetics (bezel and wheel) and upgrade into the harder plastic vents.
 
So this is pretty cool... Could save lots of us a lot of money and save the original appearance of the car.

The front ventilation fins on the original are made of aluminum, same with the bezel. On the aftermarket, everything is plastic. Luckily, these center vents were designed these to be serviceable or something because you can remove pretty much everything that could break.

That means you can use these aftermarket vent parts to replace your broken frame clips or internal fins. Here is a comparison where I took fins of the original vent fins (top) and put it into the aftermarket vent (bottom). One noticeable difference is the white indicator for air direction is much whiter and maybe a tiny bit cheaper looking. If yours is good, you can retain it - although if I recall, these usually break for people.

You cannot tell a difference! Next step is figuring out what to do with the wheel, and probably assembly.

Screenshot 2025-08-06 at 4.48.48 PM.png
 
Wow, sad to report that everything fits EXCEPT the top of bezel. They made the groove where the bezel fits in way too thick. Which is funny becasue the bottom groove is a perfect fit. Not sure why they changed it, that's aftermarket for you!

If you need new fins or indicators, it still isn't a bad option, otherwise the case is junk in terms of replacement.

As a side note, there is an overwhelming amount of knock offs out there. Be careful!
 

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