Center vacuum element replacement

Hello all,

What is the best way to do this repair. I hear that I should remove the dash but how is that done, are the bolts easy to get at?

Can I do it from the side by accessing it from the glove box?

I do appreciate all of your help.

My mechanic said that he would charge me 5 hours labor to do the job. Should I expect that it would take me that long?

Why did they put that part in such a bad spot? and Why does that one have to fail and not an easy one?

(I already know the answers to the last 2 questions)

Thanks for your help

bob

Sorry for the omition

My car is a 1984 300d


Thanks

bob

[jcyuhn]

Hi Bob (Gawd, I love writing that phrase!)

Been there, done that. I've heard rumors of mechanics that can repair this problem without removing the dash, but I don't see how. They must be a whole lot smaller than I.

I pulled the dash to replace the element when it gave up the ghost in my old '84. That said, I didn't completely remove the dash - you only have to free it up enough to pull it out of the way a bit - this saves some time & effort. I think it took me about four hours to do the entire job.

Until I got around to dealing with the issue I just wedged the center vent open. This isn't too hard to do - just remove the glovebox, pull the rubber boot out of the way, and prop the door open. Here in Dallas we can count on requiring a/c out of the center vent until, oh, about November.

As for why this one fails, that's easy. Of the five actuators in this car, four of them are on the underside of the dash, easily accessible through the footwells after removing only the undercover to the dashboard. This one is just under the (black...) surface of the dash, right in the center. The sun can do a much more effective job of cooking it there, as opposed to the others. That and Murphy's law...

Thanks for the replies

I got it in in about one hour.

I replaced the diaphram out of the new part and reassembled it in the original casing. The trick to it is maintaining vacuum while putting it together. I use two feet of rubber vacuum line and applied gentle vacuum while snapping it in to place. It worked the first time. I practice for a few tries before I went up there. while working from the glove box side remove the rubber air duct that goes to the center vents as it allows for easier access. Also have a nut and bolt ready to secure the element to the vent door. Replacing the rubber air duct was not that difficult.


Hope this helps


bob

[RunningTooHot]

Hey TheBob: One hour?! Very clever approach. Two brownie points for that one! At least I now know that it isn’t *that* dreadful if the one on my 123 goes out.

Oh, how I wish it were that easy on my 107! That requires that you *disassemble* the air box, as the element is INSIDE of it! Tons O' Fun, dontcha think?

Brother of The Benz, Bob
Consider the age of your beloved and the labor required to gain access to any one of the vacuum elements.
Remove the A/C, heater housing assembly completely.
Renew every serviceable component, i.e.
vacuum elements
evaporator core and expansion valve(the evap comes with a new x-valve and seals)
blower motor assembly complete
replace all of the seals and gaskets in the housing
completely disassemble the housing and thoroughly clean it
inspect the heater core and replace if required
Your assembly has lasted 17 years, why not give it a new lease on life?
I recently had my unit rebuilt on my 1987 300E after 14 years and 177,000 miles as I'm recommending to you.
In addition I had the compressor/clutch and the drier/reciever replaced. The condensor is alright and to rreplace it does not effect the low pressure side of the A/C.
Mine is a one owner, that's me, Benz; and I intend to drive her until I can't drive any more.
It ain't cheap, but do it right and do it once. Don't have a component fail next month that was overlooked today.
Happy Trails Beep Beep from The Spiderman in Houston!!!

Spiderman

I agree with you about repairing before it goes south all on its own. At least we can avoid alot of excessive diagnosis. I replaced the swithover valves and control unit and two of the elements. I have considered changing the other before the summer is over. I think I need a deserving rest from auto repair. In the two months that I own this car I put in new shocks, injectors, brakes, fuel filters, trans fluid, retrofit the ac and halfway rebuilt the climate control unit, new battery, new michilin tires, headlights, and drove over one hour to buy some delvac 1. But where else could I have such a nice car for the money that I paid for it. I get some flack from my family that I am excessive with my cars but I dont think so.

I am thinking about replacing the reciever and dryer and evaporator. But I am tired and my other car needs work.

Thanks for all your replies.

bob

Brother of The Benz, The Bob
Consider how long the repaired units lasted and how much longer the new units will last.
This is amunition to defend your actions to your family members.
There is nothing as sweet as an old Benz that has your personal touch added.
For those of us who aren't physically able to do the repairs, it's as sweet!
Happy Trails Beep Beep from The Spiderman in Houston!!!