Richard
Those two rubberball drains are the ones that drain the vent intake(scuttlebox) and if they become blocked you can have serious problems. I wrote a longish article about this and the problems created, for Dorians site, which is still there under "frequently asked questions" I believe. Dan Caron wrote about the softtop compartment drains, again on Dorians site. I don't know if there are other drain plugs ?
Richard V
I found the articles on Dorians along with Dan's reply;
Hey All
Since everyone is busy doing spring maintenance, I thought this might be an appropriate time to remind everyone to clear the drain tubes for the ventilation air intake box (scuttlebox). Just to make sure we are clear on this, I'm referring to the air scoop under the windshield. Water and dirt get in through the opening and drain out through 2 rubber ball like fittings on the engine side of the firewall. One is located near the exhaust headpipe the other is below the brake booster/master cylinder. These will allow the free flow of water but can become plugged with tree needles, leaves, etc. When this occurs water can become trapped in the tubes, backing up and into the interior of the car. If the connecting rubber hoses are in good shape (found under the dash above the footwells)leaks may not show up. Water will be accumulating where it should not be. After a time the metal tubes may rust through and then the water can build up in the firewall crossmember channels. These channels can hold considerable amounts of water (several litres)as they are continuous from side to side.
You don't want this to happen. Your car is now rusting from the inside out and you won't know for some time. This is the voice of experience, as I presently have most of my firewall crossmember cut out, only posibble because the engine is out of the car. A formidable task, as the crossmember passes through the inner fenders to the outer corners of the cockpit, and is welded to the firewall. This job will likely cost me $500 CDN for parts and several days labor and could have been prevented by an annual clean/inspect of these drain tubes. The damage was "apparently" minor, with a small rust hole around the pass. side drain tube. The extensive corrosion was all on the inside, eventually eating through to the pass. footwell.
Squeeze the rubber ball and make sure these tubes aren't blocked. Run a small wire up the tube to make sure.
Of course if anyone should find such a problem I'll be taking repair bookings starting next week
Richard V
I read this advice the other day with interest and decided to do it this weekend.
Unfortunately it rained very heavily last night, after a nice 2 week dry spell, and this morning the front carpets are soaked. I haven't had time to figure it out yet but just drying out the floor is enough work let alone finding the cause and cleaning out the gunk !
I've seen the tubes on the engine side and cleaned one out, it was semi choked. The other side is more difficult as mine is right hand drive, and consequently the brake booster, steering box and exhaust make access difficult.
Anyway why do these tubes enter the car at all anyway?
If leaves and rainwater come in through the front scoop I assume they are coming in the same way the air should and therefore into the car that way. So this whole area where the air should travel fills up with water !
Am I right Ben
Ben
The vent intake has to be drained as water will enter when driving in the rain. The air has to travel through the heater core/vent chambers but you don't want water here. Since the air chamber is in front of the heater core and inside the car the water has to be drained back through the firewall. There are 2 rubber connecting hoses from the bottom of this chamber to the metal tubes which actually exit through the firewall. These rubber tubes(1 each side) can be seen by removing the underdash kick panels and laying upside down on the floor
Most all vehicles have to drain away water which enters the grills below the windshield, the arrangement is a little different in our cars, due to the scoop, but not much.
There are other sources for wet floors; windshield wiper arm gaskets, soft/hard top and side glass gaskets, wiper motor chamber drain holes, and not to be forgotten is dried out windshield rubber gaskets, leaking around the glass, a common occurance in older benzes which can lead to rotted floors, as the water sits undetected under the mats. These windshield rubber/gaskets should be renewed probably every 10 years. If you are not sure, check them next time it rains. Look for a little trickle in the lower inside corners of the rubbers, next to the glass, front and rear on the hard top or sedans. This can soak your backing mats and not get the actual carpet wet enough to show it.
Changing floors panels is not as much fun as driving
Richard V
Hi all.
I've done a lot of these repairs over the years. It surprises many just how much time you can spend trying to make everything work.
On the subject of water getting into the car , here's one that not everyone knows about.
In the soft top well are two drains at the front where the top bolts down. These are actually rubber tubes and they can easily become plugged. If your top rubs against the seal it will slowly wear it away leaving a spot for water to enter. The channel that holds this seal often rusts away and this also allows water to get in.
The seal itself has a drain where the channel in the rubber starts. There's a small hole and the water drains through it and hits a baffle on top of the wheel house and then exits just above the rocker cover between the door and wheel opening. There are two drain holes at that area and they too can get plugged. A good shot of air will usually open it back up.
Water in and of itself is not so bad. It's when it lays in one place for a long time on a continual basis that you will have problems.
Regards,
Dan Caron
