water leak in body

[matinee]

I've got the strangest problem with my '87 560sl: When it rains the floorboard below and behind the passenger seat gets soaked. Plently of water coming in, but only just right there. I've checked all over for holes, but no luck. The most I'm finding are what could be small cracks in part of the lining, but they don't appear to go all the way through. Would this be enough to let a lot of water in under the car? I'm pretty sure it's not coming in from anywhere up top. Any advice?

[cmp21]

Ive got the same problem with my '88 560sl. A mechanic friend told me that the water is coming from clogged drains by the front hood hinges and leaking through the firewall to the lowest point which is on the floor behind the seats. That being said...he hasnt been able to fix the problem. I now have rust under the hinges and the water is still getting in so let me know if you find a solution.

[ctaylor738]

A couple of possibilities:

- rust-through in the cowl, either inside or outside the blower cavity. You need to remove the blower cover to check. This can be caused by plugged AC drains (inside blower cavity). If not too bad, can be band-aided with some fiberglass.

- plugged cowl drains, located outside blower cavity

- plugged fender drains. This is sort of a mystery. I believe that water entering between the fender and the hood and between the cowl and the hood is supposed to drain rear-wards to the door. That means there needs to be a passage in back of the hood hinge. If there isn't or if it's plugged, then the water will run down the firewall and find a way into the cabin. See if you can stick a coat hanger or a piece of wire under the fender/cowl by the hinge to see if there is a channel there. I have a feeling that when a fender gets replaced, the body guys may seal that passage up.