Center Vent job Update - PeachParts Mercedes-Benz Forum

afmcorp · #1 08-02-2004, 02:34 AM

Well i started & so far it's been just fine. i'm using the pod popper and replacing just the diaphragm.

i got a couple comments and a question or 2.

first off the pod popper tool is extremely hard to pop the pod open. so i'm going to modify the tool to give more leverage to squeeze. i'll post fotos later. got easier the second or third time i opened it up. but i could not get enough leverage by hand that 1st time.

now while the diaphragms seem to work you need to cut away some of the bottom one so you can insert the replacement so far so good. but it took me 2 or 3 times of putting it together before i felt comfortable with the seal

now i'll ask the question. on the one double pod you see thru the glove box the very top nipple operates plain as day vaccum and it pulls the lever in. the lower nipple thou goes to the center of the pod and as yet i'm not quite clear as to what it's purpose is. pull a bit of vaccum and it won't move the pod by itself but it does seem to help the other diaphragm. just curious

the center pod was actually not hard at all to remove the 4 screws holding it's bracket but that rod is impossible to get out of the flap's holder and i guess it's a plastic clip. i worked at it for maybe an hour and there just does not seem a reasonable way to control the actuator rod let alone take it out of the clip. i even removed 2 slide clips that seem to hold the box together thinking it would give me the access to the flap but no dice. SO i had an idea i want to share and maybe get some feed back on.

i've got a 50,000 rpm die grinder that's very small. i'm thinking i can cut a flap in the side of the vent box to allow access to the end of the rod. this would allow you to push the rod out of the clip while supporting the flap itself. i'm thinking this would put the flap and the rod in less risk of something giving in and breaking.

what concerns me is the closure. now i figure duct tape might last a couple of years under the heat and cold before drying out the adhesive so i'm thinking about gluing a larger piece over the hole using high heat silicon. i figure that ought to last till i'm dead & gone and then it would be the next guy to own the car's problem to deal with.

now i figure there is some factory trick to handling this rod and flap issue but i don't know the trick so this is my solution. i surely would like some feedback on this or maybe a good alternative to cutting up the box.

in the morning i'm going to try grabbing on to the flap with a pair of forceps and pushing the rod over with a long screwdriver but if that fails then i'm left to the old die grinder and a hole.

looking for some advice!!!

sixto · #2 08-02-2004, 11:25 AM

In replacing the center vent actuator diaphragm, I cut away as much as I could of the existing diaphragm and used the kind of replacement diaphragm designed for the second chamber of a dual chamber actuator (one has a slot, one doesn't).

The recirc actuators behind the glove box and all except the center vent actuator use a bayonet mount. Take note of how they're installed and pull them out to service on a bench. dual chamber actuators have an intermediate position between full open and full closed. The recirc actuators work in parallel. Pulling a vacuum on the outer chambers pulls the flaps to about 85% closed. pulling a vacuum on the inner chambers pulls the flaps to about 15% closed. Pulling a vacuum on both chambers closes the flaps all the way. Or something like that.

Sixto
95 S420
87 300SDL

afmcorp · #3 08-02-2004, 08:09 PM

well i got the center pod off the flap with clamping a forcep to the flap and twisting the pod's rod. [no snickers] so i did not have to cut a hole or anything of the sort.

now the center pod worked really well with the original tool. just popped right open. much more tab exposed so the tool was actually bending the tab and not trying to crush the body. so now if it goes back in as easy as it came out [of course they never do] then it's not too bad to do this job.

i will be posting a few fotos of the tool i modified for leverage.

afmcorp · #4 08-18-2004, 05:31 PM

well the job went quite well. for the center vent i found the secret to re - installing the single center pod with it's mounting bracket. the secret is a 56,000 rpm die grinder with a 1/8" carbide end mill. a little zip here and there and the hole is now bigger so you can move the arm far enough to the left to pop it in. if you've ever done a center vent job on a 126 you'll know what i mean.

one of the photos i have attached is my mytee vac. that gage is showing a couple of psi vacuum and that was sitting attached from fri nite about 8pm to mon nite 8pm. 3 days and it's still holding vacuum. i'm happy with the outcome.

the only thing i would mention is on the dual actuator pod setup the one behind the glove compartment. just don't forget to set the indexing and the right and left. i missed doing that and it cost me an hour and repeated tear aparts till i got the pod and the nipples just right.

all in all i figure it's a 4 hour job for the DIYer if you have all the parts you need.

one shot is of the dash hooks i made. i use 1" bar stock drilled an 1/8" hole thru the bar stock then milled a 1/8" .125 slot in the back of the handle then lightly tack welded the rods in place. back of the handle is flat and the wires are indexed correctly. i pulled my dash at the same time because i am repairing the clock. it stopped so it needs the 2 small caps replaced. i have a set of white face dials for my 88 but maybe i'll use them in the 87 cause i am considering replacing the clear dash bulbs with the orange color bulbs. i have always liked the dashs i've seen. seems easy on the eyes.

the 2 actuator pods you see are the ones i mentioned about being sure of their indexing.

so good experience. i think i'll just do this to the 88 for GP

I must add that i think the job went so well was because of Thomas Pindelski's website. i had his 90+ fotos on my laptop in the front seat with me and i was able to browse up and down to see what was coming or what i should be looking for. i think i heard you folks say this is something like 2k to 2500$ i've got 63 $ invested and that is the pod popper and 10 diaphragms. the 30$ fee on Thomas's site was made up so many times on this 1 job alone.

there is one caution i will give. the pod popper doesn't quite give you enough leverage to crush the dual pods. the single one i did get to work but i had to use pliers on the tool. so i modified the tool by taking the wire off the plastic handle and attaching them to a set of pliers. now i get all the force i need out of one hand and the pods open up simple.

give this a try you'll be glad you did when you realize how much $$ you save.

afmcorp · #5 08-18-2004, 07:11 PM

as is with my luck i started the 87 and everything seem fine air out of the center vents and everything seemed to switch up down on off. well fine. so while i'm tinkering around i am playing with the button on ccu when all of a sudden much to my surprise as they say the whole thing seemed to shut off. so....

now there is no center vent just like before and the the 3 pods you can see in the glove box seem to not be working very well. so i pulled the rubber hose connection to the vac manifold and wow i can't feel any vacuum. obviously there is a little because i can see the single dual chamber in the box moving but not far and no way fast.. the dual actuator pods don't seem to move at all. now down below the ccu there is another vacuum item that has a lever that connects with a plastic rack and pinion gear. it moves but very very slowly. so i am figuring not enough vacuum so i have looked at the y connector that attaches to the 2 red vac lines and it's a bit hard and loose at best. so tonite i'll get some new vac lines and see.

question.... am i missing something. i'm taking any and all tips

RAYMOND485 · #6 07-02-2005, 09:40 PM

1984 300d No Air Output Center Vent Replace Vacuum Pod. Tool Work Ok. Remove The Center Vents And Small Hands Do It By Feel And Remove Glove Box To Replace Outside Air Actuator And The Defrost Actuator On The Driver Side Trans Is Dual Actuator Buy New One And One For Floor Heat Go In Right Trans Side Use Long Flat Screwdriver To Release Long Arm Clip And To Driver Side Water Pumps A Large Pliars To Rotake The Actuator, To Install
Go Left Side Rotate To Lock On Than To Right Side And Push On Arm
Hard