rear side vents behind bumper??

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Nickdog
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rear side vents behind bumper??

Post by Nickdog » Tue Sep 25, 2012 5:36 pm

after closer inspection of my leak i have found that my rear window doesnt leak! hurray, it moves but doesnt leak, result!
however on pouring 2 watering cans of water over it i found a leak from a little black box inside (i had the interior out at the time) which im told is a vent. what are they for and can i do away with them by taking out and welding up? i need to remove the bumper to see if there is any rust but cant see any inside.

thanks for any help

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glasgowjim
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Re: rear side vents behind bumper??

Post by glasgowjim » Tue Sep 25, 2012 6:49 pm

if you look carefully at the bottom left hand of the picture below just behind and below the aerial you can see the black vent block. There is one on each side in the same location.

Image

When you close a dfoor or the rear hatch where does the air go? out the little vent blocks they equalise air pressure. each block should have 4 little diaphragms on them sometimes they just break off ( in true volvo style not the most robust.)

Oh and be VERY VERY VERY careful when removing the rear bumper as the metal cross member is no longer available and second hand spares are extremely RARE !!!!!!!!!!!

ie as in damage the one you have and you are well and truly Fecked !!!!!!!!!

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glasgowjim
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Re: rear side vents behind bumper??

Post by glasgowjim » Tue Sep 25, 2012 6:58 pm

best to leave rear bumper alone unless you have to remove it.

Nickdog
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Re: rear side vents behind bumper??

Post by Nickdog » Tue Sep 25, 2012 7:52 pm

thanks jim. ill leave the bumper on, but how do i stop the leak, the vents only come outwards? or is this a leak that drains? sorry im new to the 480.

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glasgowjim
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Re: rear side vents behind bumper??

Post by glasgowjim » Tue Sep 25, 2012 10:08 pm

the leak should drain.

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Van
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Re: rear side vents behind bumper??

Post by Van » Wed Sep 26, 2012 6:04 am

These vents are to let out air when a door or the rear window is closed. As Jim says.

I'm investigating a water leak myself and I wonder if its coming from there? There was always a very little bit water going over the trunk floor to the spare wheel hole. I had some old magazines in there and that was enough to absorb it.
However the leakage has increased and I am searching for the source of the incoming water. So far I only can find the water on the trunk floor, not anywhere higher. But if the vents are the cause, how would the water go up there when the car is not moving?
after over 10 years parted with the 1995 Volvo 480 ES 2.0

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glasgowjim
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Re: rear side vents behind bumper??

Post by glasgowjim » Wed Sep 26, 2012 1:50 pm

I have discovered a way that the water enters the trunk , the water rises by capillary action UNDER the rubber seal and then runs down into the boot.

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GTT_nl
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Re: rear side vents behind bumper??

Post by GTT_nl » Sat Sep 29, 2012 9:48 am

That's correct, just at the rear corner of the rear window rubber's lower part.
Due to a lot of junk piling up here the window arches could even get rusty here.
Don't forget to check the rubber hose at the lower part of your (electric) aerial.
There should be a appr. 6 inch of tube going from there through a hole in the chassis just below the aerial and a bit to the front and thus leading the water out of the car.
This hose is often either loose or not removed when changing the aerial, or just as worse :boom: too short and left hanging halfway, obviously not knowing what the function was.
If this is the case water can slowly enter past the sliding aerial parts through the mechanism down in to a place one usually never tends to check and cause trouble on the long term.

By the way, in the vent-blocks there should be rubber flaps, two double flaps interconnected with a small piece of rubber, placed longitudinally over the vent hole's just over eachother fixated between two plastic parts of the vent block ,very thin material this rubber, so handle very delicately when checking!
If these connections dry out (of age), the flaps can hang loose, thus not preventing (condensed) water from coming in.
If you should ever remove the rear bumper (always use some lubricant on the sliding plastic brackets on both sides on which the bumper is placed, sold out, so brake it and pain is the only thing you get at Volvo's!!!), you'll notice a lot of crap/mud/debris on the inside of the bumper near the vent blocks, maybe even in it.
So how it get's there??? Not the foggiest, but it gets there for sure!

The biggest problem of removing the rear bumper is not the metal cross member in my opinion. This might well be rusty or even missing on a few square inches, but it's not a part of the structural integrity of the rear bumper, at least not the part where it rusts away (which is usually at the sides).
The hard part is removing the nuts from the fixating bolts, bl**dy annoying! You'dd have to start spraying it with WD40 well ahead, weeks before you even try removing it. Furthermore the towing bracket (right term?) might be rusted with it's fixating nut to the metal member's bolt, but this you can cut out after removing the cross member.
Getting a new or second hand metal cross member in good shape is the hardest part indeed.
I'm all for discovering how my car works, and enjoy every second of taking it apart and putting it back together again, still on an amateur scale, but enjoyable nonetheless. If you would want to remove the bumper just for learning how it works, I'dd advise you to look up a 480 on a scrapyard and remove the bumper just for fun :hopping: , that's how I learned and you might just find one of the few left intact inner metal cross members, or even a pare of nice rear clusters! Good luck!

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Van
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Re: rear side vents behind bumper??

Post by Van » Tue Oct 02, 2012 6:15 pm

I don't think my water is coming in from down. I washed my car today. Before I had changed the papers for dry ones. Immediately after washing there was serious water intrusion making the new papers really wet. When I lifted them there was water on the floor. My guess is the side window or near there.

I have checked the rear window, which I had worked on, again and again but never found a trace of wet suggesting it may come from the wiring entry. While I was working on it, I had closed the gap with the remaining end of tulle, and even went out at night after rain to check the insides of the rear window and all was dry.
after over 10 years parted with the 1995 Volvo 480 ES 2.0

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Van
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Re: rear side vents behind bumper??

Post by Van » Mon Oct 08, 2012 8:20 pm

My brother kindly allowed me to work at his place and I removed the interior trim in the boot and investigated with a hose. First thing I discovered was the side marker was not 100% tight. I removed it and sealed it with the expensive silicon kit.
This is not to bad I thought, found and fixed it, good story for the forum.
Then tried again with the hose and I heard water pouring in. Now it seemed to come in lower. I removed the aerial and tried again. When pouring water on the side of the car, water came in through the vents assembly and the vents. The vents are constructed exactly as GTT_nl describes. First I sealed the vents case as much and as good as I could. Then still water came in through the lower flaps. It turns out the lower flaps aren't closed firmly I assume by a bad spring or so.

As it was advised not to remove the rear bumper and was not able to anyway I thought best was to just block the lower flaps. After consulting the DIY store I used polyurethane spray-foam to close and block it. Since this stuff takes time to harden I have not tested it with the hose. Also I ran out of time. I reassembled the trim and had one large screw left over. Now keeping my fingers crossed. So far no negative effect on closing doors or rear window.
after over 10 years parted with the 1995 Volvo 480 ES 2.0

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Van
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Re: rear side vents behind bumper??

Post by Van » Fri Oct 12, 2012 8:27 am

Rain is pouring down and I just had a quick peek in the boot: all seem to be dry so far.
after over 10 years parted with the 1995 Volvo 480 ES 2.0

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Van
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Re: rear side vents behind bumper??

Post by Van » Fri Oct 12, 2012 4:59 pm

After more rain there is some wet in the boot. Have not checked from where. Not as bad as before though.
after over 10 years parted with the 1995 Volvo 480 ES 2.0

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