That may be correct.??? the door is normally open.....pushing the button closes it
so said conversion door would normally be closed, as in key off, better for your rodent idea!
I'm going to use the wedge or wire my recirc door shut as well. Can anyone please post a pic of how they wired the door shut? I'm sure its pretty simple just curious as to what works.mine just popped out again, still not broken just slipped out somehow again, i didnt fix it, i wired it closed, no need for fresh air on this thing!
If i realy need fresh air, ill open hood and pull wire off.
Bruce,Since I wrote this, the belcrank on mine broke. Dodge, MB or Valeo (that's who makes the air distribution system) do not offer the small bits and piece parts. By happenstance, I found a company that 3D printed a replacement belcrank for me. It's a perfect fit and has been installed for several months without any problems.
Working on it isn't hard, but it is time consuming because you are mostly working by feel due to the location of the parts.
The actuator is held in by two screws, a vacuum line and an electrical connector. Remove the fasteners first, then you will have better access to the actuator to remove the connector and vacuum line.
The belcrank is notched on the actuator end at a location that keeps it from becoming disengaged.
Here is how I installed replacement belcrank and actuator:
The actuator has to be fully retracted during installation to give you the necessary room. I used safety wire to keep it fully retracted until it is fully installed and the flapper arm is installed onto the belcrank pin. The full retract position is also the recirculation position - flapper door closed.
Install the belcrank onto the actuator end. Carefully install the belcrank/actuator assembly onto the belcrank shaft. Do not try to fit the pin into the flapper lever - it gets installed as the last step.
After the belcrank is in place on the shaft, install the actuator fasteners, connector and vacuum lines.
Using a long screwdriver, long thin yard stick - push/deflect/slightly bend the flapper lever enough to fit over the pin on the belcrank. I would recommend applying heat from a hair dryer to make it more pliable.
If I could have easily removed the flapper lever, I would have. I believe it is held into the flapper door by lock tabs, but I didn't want to risk any damage.
Remove the safety wire from the actuator and test operation.
Hope this helps.
Bruce
UPDATE: after almost 4 years of use, my bellcrank repair was still functioning, but since I had to remove my ventilation housing for another repair, I inspected it and noticed a lot of the superglue Qbond material was gone and the pin was loose. I'm now trying 2 part epoxy to hold the pin in place, which will hopefully last longer.I thought I'd toss in my low-cost repair for this lever / belcrank or whatever you want to call it. Mine was also broken and looked almost identical to bc339's in post #12 of this thread. I didn't want to spend $50 on a 3D-printed one nor did I want to whittle one from a block of Delrin I had laying around (although I did think about it). I was inspired by Aqua Puttana's mention of using a nail. I mic'd the OD of the good pin at exactly 5.0 mm (knowing Mercedes would use metric everything) or 0.196". I wanted something close to that diameter but couldn't find any nails that size and didn't have any M5 metric bolts with shanks laying around. A #10 bolt shank is 0.145" diameter, so a little small. I settled on a 3/16" diameter (0.187") drive nail anchor (pictured) for $0.33 at ACE hardware.
Then I had to drill a 3/16" hole in the arm. I didn't trust myself using a drill accurately without messing up, so I used a 3/16" endmill since I'm fortunate enough to have access to a machine shop.
Hacksaw off both the ends of the drive nail anchor after measuring the length you need, leaving the head on; insert it in the hole from the back side and then Q-bond the $%&@ out of it for reinforcement. You're left with a pin that's stronger than the plastic one on the other side. If you've never used or heard of Q-Bond, GET IT! I haven't found anything better for repairing/reinforcing little plastic auto parts.
Hi Doug, I am also having problem with my recirculation, and will need to remove the housing to fix the recirc door mechanism.UPDATE: after almost 4 years of use, my bellcrank repair was still functioning, but since I had to remove my ventilation housing for another repair, I inspected it and noticed a lot of the superglue Qbond material was gone and the pin was loose. I'm now trying 2 part epoxy to hold the pin in place, which will hopefully last longer.
ALSO A TIP (since it wasn't obvious to me the first time): my original repair was done trying to work my hands in on the side of the ventilation housing with it installed in the van. This required some blind work, lots of hours and swearing. Having recently removed the ventilation housing, I recommend doing this for any repairs to the recirc door mechanism. Contrary to what the service manual appears to say, the ventilation housing can be removed simply with 5 nuts and a couple electrical plugs. The wiper fluid reservoir, all refrigerant lines, coolant lines, and even the turbo heat shield can all remain in place to remove the ventilation housing and then working on the recirc door mechanism is so much easier.
I have actually done this now, and it has been working fine for 6 months. So its solidly in recirc mode all the time even with the engine off. In fresh air mode it opens the flap blade about an inch, so its not a true 100% fresh air solution, but it works for me.Has anyone thought about somehow reversing the bellcrank/actuator/spring mechanism so that the door is open when the button is pressed, and is in recirc by default? I though about doing this by swapping over the actuator to bellcrank pivot. It would require a slight re-mounting of the actuator, but other than that it should just work*.
Any chance for a picture(s)? Others may want to copy what you did....
I guess it could be made to work better, because all I did was hack off some plastic and re-mount the vacuum actuator so it worked in reverse. Crude but totally effective for want I wanted.
A bit off topic, but has anyone mouse proofed this air box opening in the engine compartment without significantly sacrificing air flow? I have no rodent infestations, as far as I know, but have used hot paper tape on the wiring and a few pellets here and there of mouse 'deterrent' where it won't blowoff or get sucked in when on the road.
I think this air box housing is definitely a marginal design, the wall is just too thin. Mine has the same problem, there is a crack around the base of the hinge pin which causes it to wiggle a bit when under force, I believe that was the reason why the linkage broke on mine. I used the approach showed in post #24, but I glued a piece a plastic instead of wood and it works and should last a long time.