1980 300SD - shutdown problem with CCU Set to Off/Lo/High

[ckamila]

Alright, i am in!

Defrost pod leaking, center pod holding vacuum. Need to double check Defrost just to make sure i have other end capped.

George Murphy email bounced...can someone provide valid email? I found it via search but did not note location.

Anyone have experience with the pod poppers? Provide picture of popper?





Thanks for all the support...i know i will need more.

[jbrasile]

Chris,

Nice work! Same exact problem I had, only the defrost pod was leaking.

Try this e-mail for George Murphy:

perfanalysis@comcast.net

I did not use my pod popper when I changed the pod internals in my car, I actually forgot I had one and ended up braking the little tabs to separate the two pod halves. Luckily I was able to re-install everything without any issues even with the little tabs partially ruptured, I did however test the popper on an old pod and it seems to work quite well, I will try to post some pictures of the tool when I get back to the office later this week.

Keep us posted, you are doing a great job documenting your work.

Tks,

Joe

[ckamila]

Hi Joe - That looks like the right address. I searched all through the "george murphy" and "center vents" posts but did not locate it again. The email link from his web site lists an old provider, george_murphy@compuserve.com. New message send without bouncing back. Thank you!

1980sdga - Searching the older w116.org ACC posts from you and Joe...just wanted to thank you too for the posting of servo.pdf, etc.

[1980sdga]

Let us know if you have trouble contacting Mr. Murphy. I have a phone # I can PM you. He has been hard to get hold of but he's very legit. He will mail you some really useful technical info as well as a catalog.

Like Joe said, the system is pretty complex (Not impossible as you're learning  ) and relies on all the components to function. Lots of folks have looked for shortcuts and just end up mutilating their cars trying to get something working.

I would encourage you to rig up an electric vacuum pump to test the vacuum system without the engine running. I re-purposed a breast pump  that stood in for the engine driven pump. It's really convenient to run the vacuum system through its paces without the diesel rattling away! I've seen 12V vacuum pumps for diesel trucks that would be better but they're about $100 and I like building stuff 

Here's my makeshift pump:

 

Keep up the good work!  I don't think it's a bad idea to just focus on the heater.  It's a really nice system and I'm really impressed with the heat. Especially when you just need a little heat to stay comfortable. It also works well with the furnace roaring but once the cabin warms up it does a good job maintaining temps without getting too hot.

You'll have to get the fresh air flap (The blue pod under the glove box) working like Joe said in order to enjoy, well, fresh air. It works well for getting a little cooler air into the cabin and is really nice when it's raining or muggy and you don't need to run the AC compressor.

I also appreciate your documentation!  So many people just give up on ACC but they're missing out on something that makes the car sooo much more enjoyable  The more the merrier!

[ckamila]

Hey Jon - Thanks for the pic and the idea. Too bad though, my wife used a hand pump for our 3 kids daily supply of milk.

Fresh air pod is working even though it looked bad from the leaking oil but cleaned up well and still works. I do need to check the floor vent pod (drivers side i believe) to make sure it is working fully as the quantity of air is low in my opinion.

[ckamila]

Just ordered a kit from George Murphy to replace all diaphragms while system is dissembled

Current George Murphy contact info:

Pod popper is $10.95; diaphragms for vacuum actuators are $6 each, S&H is $.9.95

perfanalysis@comcast.net
Visa/MC/Dis/PayPal

Performance Analysis Co.
969 Oak Ridge Turnpike, Suite 258
Oak Ridge, TN  37830

865-482-9175   Voice
865-482-7260  FAX

9 am to 5 pm ET Monday -Thursday
until 1 pm Fridays

[ckamila]

How do these things happen...simple shutdown issue and now I'm going all the way pulling the dash to fix the buggers.

Cluster came out over the weekend. Disassembled, cleaned all gauges and needles but did not repaint. Polished the plastic windows and installed all new bulbs. Inside of clear plastic window very dirty/oily and the clock's hour hand almost black. Is there supposed to be a gasket between front bezel, clear plastic widow or main body? These is a ribbed rubber gasket/seal on back of main body.

Everything is mostly out just last few items so i have several questions: is it easier to pull the steering wheel and seats before removing center console and dash? I was planning to pull the passenger's seat at some point to cleanup the rails and such.

Are the front speaker grill rear sections just snapped in? Can't see where the hang up is and don't wish to break them. What direction to pull/pry, just up or to the rear? Front screws are out, speakers are mounted on top of dash. My pre 78 FSM shows them on the dash face for some 116's.

While i am in there what else should i do besides diaphragm replacements? How much trouble to pull/clean condenser? Are there any a/c o-rings to replace? Car is in my mostly dry garage and i have another car for transportation.

Any other hints or tricks?

[jbrasile]

Wow Chris, you are going all the way....


Are you sure you want to pull the dash out? It is possible to replace the diaphragms with the actuators in place, yes it is fiddly and you need hands with more joints than a Transformer.... but doing  it that way will avoid any possible damage to the dash itself.

At any rate, answering your questions:

No gasket between lens and main body of the instrument cluster
Speaker grilles - once you remove the screws pull them towards you without lifting, they have two little ears in the rear. You may want to help them slide out by pushing from behind at the same time. Usually the ear towards the outside of the car will let go first.

If you decide to remove the dash, replace all the vacuum actuator diaphragms, check all the vacuum rubber hose connections and check valves to make sure everything is in order and go over all vacuum lines. Cleaning the a/c evaporator, condenser and a/c box involves removing the complete assembly, dismantling it and doing a complete tear down and rebuild,  not terribly complicated but very time consuming. While you re in there, replace the a/c expansion valve as well. With ACC you usually don't have a flap noise issue from deteriorating foam, but it wouldn't be a bad idea to replace all of it to make sure all the air distribution doors work quietly and smoothly. I don't think there are any o'rings to replace at the evap or condenser.

I congratulate you on your efforts! Very few people would be brave enough to tackle an ACC rebuilt!

Tks,

Joe

[ckamila]

Are you sure you want to pull the dash out? It is possible to replace the diaphragms with the actuators in place, yes it is fiddly and you need hands with more joints than a Transformer.... but doing  it that way will avoid any possible damage to the dash itself.

Joe - Well i certainly don't want to create a larger problem! Where might my sticking points be or are your speaking about the fragile nature of the dash in general given it's 32 years?

I just don't see how i can do it with the left side defrost vent in the way. Now if i can remove the left defrost vent (4 tabs; 2 against window and 2 on the drivers side, lift up to clear rubber boot) great. But i don't see that happening unless the dash is loose.

Should i continue forward, any thoughts to the seats and steering wheel removal to make things easier?

[jbrasile]

Chris,

The risk of cracking the dash is what concerns me the most. To clear the A-pillar you have to "bend" the ends a little and after 32 years it is very likely the injected plastic will get damaged.

Are you replacing all 3 vacuum pods? From your previously posted picture I see you have already removed the rubber boot and plastic nozzle at the top of the a/c box, if you insert the pod popper through the center vent opening and put it around the defrost vent pod,you should be able to get it opened and remove/replace  the diaphragms, same for the center vent actuator, that's how I did it in my car and I didn't even use the popper (forget I had one....). There is no need to remove the left defrost vent to do this if you are patient.

I suppose you could just get the dash loose enough to make your work a little easier, but I would try to avoid removing it completely.

If you do decide to go forward, it is a lot easier to remove the center console with the seats out of the car, so I would take them out as well as the steering wheel, the more room you have to maneuver the better.

Tks,

Joe

[ckamila]

Joe - I did not know about the bending part of the procedure. In that case i think i will loosen the remaining screws and hopefully have more room.

Yes planning to replace both defrost and center vent pods while exposed and the floor and fresh air too - i bought a complete diaphragm set from George. I tried the pod popper briefly on the fresh air pod 43 while still attached and could not get it to open. I will work on the lower pods first to figure out the best technique.

[ckamila]

So i really wish to replace the center/defrost vacuum pod diaphragms but did not have enough room with just the center vent removed so i pulled the seats, tunnel and was able to lift up the dash a bit. I was so close - i thought - might as well  give the dash a go....almost had it but window seal is in the way or something. Thought i did manage to overlap a small segment of dash material in the right-hand corner that now sticks up like a small ear. Should be able to pull it back down with a strap.

Not yet content on reeking havoc.... i had another go at the fresh air pod and did pop off top to expose innards. However to replace diaphragm a set screw needs removal to release lever which diaphragm must pass through. Well the head popped off the screw. Good thing that diaphragm still works.

Still debating on puling the dash but will probably repair/replace center pods with current access. Too bad my front windshield rubber is in such good shape. Otherwise the job might escalate further

Still having fun which is the important thing. Needed to cleanup the garage to make enough room to store all the parts. Moving at a snails pace but still moving.

[jbrasile]

Hi Chris,

Nice work!

Once you start putting things back together, use a plastic spatula to carefully push the corner of the dash back down. Now you see what I mean about the lack of space to pull it out? Imagine having to flex the whole corner to clear the A-pilar....doable, yes, but risky on a 30 year old part.

You are doing very well time wise and working slowly is the key to prevent damaging anything. As for the fresh air pod are you talking about the white/blue or the pink one? I deactivated the fresh air function in my car and after experimenting a bit came to the conclusion that  with today's traffic conditions and temperatures it is just best to leave the flap closed all the time but plugging the vacuum hoses. This has a few benefits:

1) You don't have to replace the pods/diaphragms
2) You have no odors coming into the cabin during rush hour traffic
3) On very hot days you have increased efficiency from the a/c since no warm air comes into the car.

Disabling the fresh air system has no effect on ACC control functions, flaps will still open and close as they should and temps will vary according to the sensor chain.

Keep us posted of your progress.

Tks,

Joe

[Ilike300sd]

ckamila,

Holy Moly you are brave to tackle that!  Kudos!  That looks like that scene from star wars when Han Solo and Chewy were trying to patch up the millenium falcon and wires were hanging out everywhere.

[ckamila]

Joe - Thanks for the input and encouragement.

I would like to replace all the rubber connectors under the dash but might not get that far with dash in place.

Pink fresh air pod 43 is where i had the slight mishap - since i don't currently have a functioning a/c system, drawing in cooler outside air in the summer is desirable. I have read some of your other posts about r12 / r134, seems like r134 is working for you in San Paulo - if that's you location. What type of vacuum pump and hardware is needed to test original r12 system for leaks prior to repair or conversion?

Have not located floor vac pod 41. I can account for all the others and don't know where it could hide with everything but the dash out. Maybe just blind or confused.

Chris