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From: Ron Milliet <>
Date: Thu, 30 Apr 1998 08:50:33 -0500
Subject: <E30> Water leaks...PLEASE add to the FAQ

Catherine, Greg and others:

I know EXACTLY what causes the "soaked floorboard carpet phenomenon" and how to fix it. This question has come several times recently and many times over the year. I **think** it is common to E30s and should be put in a FAQ. I spent HOURS and many gray hairs tracking down this DAMN problem. I COMPLETELY removed the interior of my car including the carpet.

Problem Description: After a rain, the carpet in the rear floorboard gets TOTALLY soaked...usually visible, standing water. Close inspection reveals that the water is coming from UNDER the carpet and rising up to the top. This is different then the...dripping down from the sunroof leak, taillight lens gasket trunk leak, and the ever annoying under the dash from fresh air vent leak.

Problem FIX (from my previous posts):

It was both passenger and driver floor boards. I wrestled this PITA problem for about one year, before I finally resorted to tearing the car apart. I finally pin pointed the rocker drains were not draining. They had been crushed closed by something. The sunroof would drain into the rocker and eventually fill up enough to spill over into the floor pan via holes for the wiring harness. This is very easy to test (details for an E30):

  • Start with car on level ground and fill the forward sunroof tube slowly with water, it should immediately start streaming out as fast as you pour it in via the "fore" drain
  • The rear sunroof tube does not drain into the rocker
  • Next point the front of your car up a steep hill and again fill the front tube, the water should stream out of the "aft" drain

My car had two drains per side. These were merely indentions in the sheet metal seam. All 4 of my drains were crushed closed. I used a screwdriver to open them and was greeted with a rush of water held in the rocker.

BTW, My car took on water once more after this. It happened when my car was parked with the front down a VERY steep hill. The problem was the "fore" drain is located about 8 to 10 inches from the end of the rocker. This allows water to pool up and spill over before it reaches the drain. This phenomenon was immediately remedied with a 1/4 drill bit!!

Hope this helps,

Ron Milliet
Project Manager, Administrative MIS
Southwest Mississippi Regional Medical Center McComb, MS

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