Q – I have a 1987 Porsche 924S and there is a water leak into the car. Every time it rains the passengers side floor gets wet. I don’t think it is the windshield since it leaked prior to having the windshield replaced and it still leaks with the new windshield. Joe
A – Under the battery, there is a clear path for water to enter the passenger side of the car. My advice is to remove the battery, clear the debris out of the area that may be blocking the drains and scrape the area clean. If the floor of the battery box is rotted out (which I am betting on) you can repair it in a few ways. 1) You could take it to a body shop where they can weld in a patch, 2) You could fashion a patch out of plastic which you can purchase at a plastic supply house, and glue it in with sealant, or 3) A piece of galvanized steel from a heating and cooling shop can be used. If you are going to have a body shop do it, they should be able to refinish it so it will be many years again before it rots. If you are going to do it yourself, a product called POR-15 can be applied over the rusty metal which then bonds to the rust. This provides a good basis for either a plastic patch or the steel patch. Bonding the patch to the area works well since the battery holds it in place until the sealant dries. That will cure the wet floor for years.
One thing to note is that both the positive and negative cables are black! Make sure you mark them before you remove the battery. If you don’t, and you are not sure which is which, use a volt/ohm meter to confirm which cable is ground. It is not worth taking any chances on this topic. – MC