The Official 356Talk Forum

Just asking a newbie question here. Under the hood next to the hinges there are two air valve boxes with screens and a cable for activation. What exactly are these called and can they be removed from the car? Reason I ask is that I will be removing my fuel tank for cleaning and new fuel lines and see that the air box on the right side is very close to the plate that holds the tank neck.

Terry, the electronic parts catalog refers to those boxes as 'flap control' boxes. They regulate the fresh air into the cabin. The shop manual does not call to remove those boxes in order to remove the fuel tank.

I removed my tank and filler plates without removing those valves

Terry,

They are valves for allowing fresh air into the car's front compartment from the entry in front of the windshield.
There are 3-positions w/the dash lever; Off, On for air, and air w/heat for defrosting the windshield.
The system is described in the owner's manual.
As mentioned by another member, You don't need to remove them for fuel tank removal.

Dick

If you do take them out for refurbishment, you'll find a few things. First, the foam that is supposed to seal the disk inside the diverter will be completely toast. Touch it and it will turn to dust. With some effort you can clean out in there and add new foam. Second, you'll see on the back side a date code. Mine below is A5 and my car was produced in January of 1965. Easy to figure that one out! Add a little fresh paint and you'll be all set.

Terry one note of caution if you decide to remove. As you see in Paul's third photo there is a stud sticking out the side of the vent. The nut that holds the this vent in place to the inner fender is in the wheel well. Chances are good that the nut is rusted on the stud. Recommend soaking the nut with penetrating oil overnight to avoid twisting this stud off.

Kudos to Paul for the green paint on the square nuts!

Mike

And if you do decide to remove the passengers side valve it is the perfect time to replace the hose from your fresh air box as it is almost impossible to do without removing that flapper box. Most 62s have a 45 degree bend neck coming off the box. So if you want to replace yours make sure which type you have 90 degree bend or 45 degree bend. viewtopic.php?t=18566

Absolutely right, Doug! Much easier w/o the fresh air valve in the way.

Mike

Unless absolutely necessary, do not remove the valves. You will soon find how difficult it is to synchronize the cables to work properly with the dash lever. Not that it can't be done but It can drive you crazy. ( And that is even for someone familiar with the cars!)

Also, removing and reinstalling them might stress the rubber Y connectors and tear them. Repros are available but pricey.

Mike

The valves are very clever and complicated with magnets to hold two parts together at appropriate times, along with gears to move things in a synchronized way.

Wow, thank you to all who have replied to my question. I will leave the flapper boxe in place and work around it. I have been working on air cooled VWs for decades. But these 356 cars sure have another level of complexity....or maybe it's just me getting older...lol