740 Estate vent in trunk - or what is it?

[lanchen]

Hi,

does anyone have an explanation of the picture?
I am guessing the Volvo engineers have been testing some sort of ventilation system. However, I find it hard to figure out how it is intended to work, since it is placed inside the car, with the rubber flaps opening outwards and lastly being covered by the removeable floorborad.

[bob12]

Hi Lanchen ... picture not attached - Bob

[lanchen]

Hi Bob,
So it seems, lets see if this works
https://picasaweb.google.com/mhspriv...o740GLT16V1989
The first icture...

[Steve940estate]

I think they are intended to let the air out. On my 940 there are vents in the boot floorboard. You get lots of air in the front of the car from the heater/ventilation system. There are also small vents at the bottom of the A post. The later cars like my 940 just had cover panels.

[lanchen]

Hi Steve,

Seems very plausible.
See I often take the dogs for a ride to the sea or the woods, that's why I have the floor covered with the black rubber lining, makes cleaning easier. However, that rubber also covers the vents in the floorboard. I always have trouble with the windows misting when the dogs are in the car. This is certainly the cause.

[Ifitantacatitsadog]

It also helps you shut/open the door by letting the pressure/vacume out Audi come up with it in the 70s

Things with big doors that don't flex will blow out sunroofs etc when the dor is shut with the air pressure they cause in sedans there in the C pillars yours are beside the boot as it it the biggest door most likely to cause a problem

[Clan]

Originally Posted by Ifitantacatitsadog

It also helps you shut/open the door by letting the pressure/vacume out Audi come up with it in the 70s

Things with big doors that don't flex will blow out sunroofs etc when the dor is shut with the air pressure they cause in sedans there in the C pillars yours are beside the boot as it it the biggest door most likely to cause a problem

The 1963 ford cortina was the first to have throughflow ventilation ! Although the 1963 hillman imp had those same flaps at the rear of the roof to let the air out .. Like most "new" inovations coming out in motor cars these days , very little is actualy new ..

[brodgar]

my understanding is that the air gets sucked out whilst driving because
of tiny underpressure (vacuum) is being created by the ventcover in the
rear panel.

Incidently, the 2 series also have a vent, it is visibly located under the driversside rear window

[lanchen]

Fascinating.
Glad I finally got round to asking.
Thanks everybody.

Now that I also learned how to attach images, I will put the picture of the vent itself in here.