INTERIOR WATER LEAK

[koab26]

OK GUYS I HAVE A 1981 MALIBU, I PULLED THE CARPET OUT AND NOTICED SOME MOISTURE. THIS CAR IS PARKED UNDER A CARPORT WITH ONLY THE HOOD/FRONTEND STICKING OUT FROM UNDER IT. I HAD SANDED AND REPAIRED A FEW AREA'S ON THE FLOOR PANS, I NOTICED AFTER SOME RECENT HEAVY RAIN THAT I HAD WATER STANDING ON THE FRONT DRIVER'S AND PASSENGER SIDE. I CAN ACTUALLY SEE WHERE HE WATER RAN DOWN THE FRONT PART OF THE FLOOR PAN ON THE PASSENGER SIDE. ANY IDEAS OF WHERE IT WOULD BE LEAKING THROUGH AT BESIDES AROUND THE UPPER SEAL OF THE FRONT WINDSHIELD. ANYONE ELSE EXPERIENCE THIS ON A G-BODY???

THANKS FOR ANY INPUT GUYS!!!

 

[khan0165]

my car has this problem. It only leaks when standing, not when driving. Water slowly seeps down and comes out at the foot wells.
On the passenger side, I've traced the problem, water is slowly draining down to under the heater box, and seeping in thru the firewall & floor pan seam.
On the driver side, it comes in from above the emergency brake pedal on the left side of the footwell. I believe it's coming down from under the wiper motor or from the rubber boot that covers the wiring from the door jam to the door.

also, these cars are known for wornout seals and metal under the windshield trim, so that would be a place to check too.

 

[koab26]

THANK YOU MR. "ROYAL SMART PERSON" :lol: THIS INFO HAS BEEN VERY HELPFUL, IT DOES SEEM TO BE COMING FROM THE EXACT AREAS IN WHICH YOU DESCRIBED IN YOU POST, GREAT ILLUSTRATION!

 

[Longroof79]

As Mr.Khan had described. Check all the body seams in those areas. Also check for rust. It's sometimes easier to diagnose with the sheet metal off. Leaks can develop in the seams behind the fenders and firewall areas. Also remove the stainless trim below the windshield to see if there's any rust holes present...and of course around the windshield frame.
Mr. Khan is on the money... :wink:

 

[khan0165]

yeah, if you examine that area, there's alot of seems, because there's alot of sheetmetal coming together at those locations. And it's a hotspot for rust and leaking.

It's very tricky to remove the fenders in these cars. It's simpler to remove with the inner fender assembly. I've pretty much taken an ignoring approach to this problem because of all the horror stories I've heard of fender re-alignment once you go to re-install the fenders.

 

[koab26]

OK HAD THE WIFEY RUN WATER OVER DIFFERENT PARTS OF MY WINDSHIELD WHILE I CHECKED FOR LEAKS. WATER WAS POURING IN ON THE PASSENGER SIDE ON THE LOWER PART OF THE WINDSHIELD WHERE THE CHROME PIECE IS BY THE WINDSHIELD WIPER.

 

[Longroof79]

Also make sure you check the area under the wiper motor. It's also a drain area where junk gets clogged up and can cause it to rust. There's also several seams that should be addressed.

 

[godlemmy]

if it's only leaking on the passenger side check the drain for the heater box.My '79 was leaking there and i thought it was the windshield,turns out the heater drain was plugged and it would back up and seep through the heater.just take off the screen on top of heater/ac box,clean out the crap,and then run the hose through it to clear the drain.I would never have thought of it except that i took the carpet out and could see where the water was coming in from.

 

[koab26]

OK GUYS, IT'S BEEN A WHILE SINCE I'VE COMMENTED ON MY WATER LEAK ISSUE HOWEVER. A COUPLE OF WEEKS AGO DOWN HERE IN TEXAS WE ACTUALLY HAD SOME MEASURABLE RAIN FALL :lol: I KEPT GOING OUTSIDE CHECKING MY MALIBU TO SEE IF I COULD TELL WHERE WATER WAS GOING TO COME FROM. BACK UP FOR A MINUTE, I HAD ALREADY REMOVED ALL OF THE OLD CRACKED UP CALKING FROM AROUND THE HEATER BOX AND REPLACED IT WITH NEW CAULK. MOVING ON, THE WATER WAS ACTUALLY COMING DOWN THE FIREWALL UNDER THE HOOD AND THEN ENTERING THROUGH THE SEAM WHERE THE FLOOR PAN AND FIREWALL CONNECT TOGETHER. IT HAD ALSO BEEN COMING IN AT THE TOP PART OF THE TRANSMISSION TUNNEL SEAM. I REMOVED ALL OF THE OLD CAULK WHICH WAS VERY EASY, HECK IT JUST FLAKED OUT OF THE SEAMS WITH MY PUTTY KNIFE. CLEANED IT OUT REALLY GOOD WITH A WIRE WHEEL ATTACHED TO MY CORDLESS DRIL AND RECAULKED IT AND BINGO NO MORE WATER HAS COME INSIDE. THANKS GUYS FOR ALL OF YOUR HELP AND SUGGESTIONS, AND YES I DID LOOK INTO EVERY SINGLE ONE OF THEM, IT DROVE ME NUTS! :evil: :evil: :evil:

 

[khan0165]

glad you sorted it out.
the seam sealer that GM used back in the day gets all dry and cracked, so it's easy for water to start getting in and rusting as well. What kinda new sealer did you use?

I still have to fix mine, I can't find where my driver side leak is coming from, without removing the dash. So I've just been ignoring it, lol