Finally fixed my leaky cowl

I posted awhile back about my wet carpets and cleaning out the cowl through the access plates and siliconing all around all the plugs on the firewall and whatnot, but the more I read on here, the more I knew it was the seam that is under the cowl, which is welded on to the body. I also read horror stories of huge rusted holes in the little gutter thing under the cowl, but I decided whatever I ran into I would just deal with the best I could...couldnt get anyworse than it is now. I got the idea from Copykat, after reading his thread about swapping a gen1 for a gen2 cowl. My dad persuaded me that if it could be broken loose on three sides, it could just be bend up toward the windsheild enough to caulk the seam. So thats how I did it. My cowl ended up being extremely clean, with no rust at all as you can see in the picture. If it would have been nasty, I probably would have hit it with undercoat. The sealant that was supposed to seal the seam was laying out in big chunks though.

I didn't remove the fenders, just all the upper bolts. Pulled it out enough to run a grinder with a cutoff wheel on the cowl panel, just above all 5 or 6 spot welds, worked great. Took off the wipers. Then off came the hood and I drilled all 20 some spot welds along the front of the cowl, not going to bad yet. Once it was free, it took some persuasion with a screwdriver and cold chisel, but all three sides popped loose. Then, with my dad's help, we peeled the cowl panel toward the cab and supported it with wood blocks at the ends. Blew all the junk out of the gutter and then caulked the seam, it was tricky, and my hands got scraped up, but at least its done now. I used a tripolymer caulk for rain gutters, it says it can be applied in the rain, under water, or on oily surfaces, and is guaranteed to stick to any metal, wood, or plastic surface-all this for 5 bucks a tube! When it was all done, took out the blocks and pushed the cowl back into place. Put self drilling metal screws back in place of the welds, and notched the rubber weatherstrip for the hood to fit around the screws. There are two small dents, one on each end of the cowl. They're just depressions that sit lower than the fender by about 1/8", not terribly noticable, and it doesn't bother me that much. I would do this again in a minute if my ranger/bronco ii was leaking through the cowl. Hope these pictures work, it's my first time using photobucket.

Here is the cut on the ends of the cowl


Here it is peeled back


This shows how clean the gutter is, and the empty seam on the bottom right.


Here's the caulk I used 5 buck a tube from my ace hardware

dang that looked like a job, i used to have a leak in my bii, it ended up being the heatercore. Thanks for the write-up!

Thanks for the write up! Do you have pics of it reinstalled? This might be an option for me since my truck is showing signs of the dreaded 1st gen cowl leak..

this is my problem to i think... my right side floorboard stays soaked... maybe its the heater core (even tho its new...)

i have that problem lol, i just have not addressed it yet, or any of the other problems with my truck yet

I didn't take any pics of it reinstalled, but I can get some this weekend. It really doesnt look bad, it's just one of those things if you look close you'll see somethin's up.

Here's pictures of the cowl folded back down into place. It had rained monday of last week, and when I called home, my dad said there was still a trickle of water leading to a small puddle on the floor of the bronco. So last Saturday, I took the hose to he whole firewall inside the engine compartment, and found out that a strong trickle of water comes right down the middle of the passenger floor when water is poured on the heater hoses. So I put ugly amounts of that gutter caulk around it and let it sit over night. I also peeled back the weatherstrip at the back edge of the hood and put caulk along it above the heater hoses so water doesn't even have a chance to get there. Sunday morning I hosed it again and it wasn't leaking. I wont be home for awhile to put everything back together, but the next time it rains I'll find out if there's any leakage.

Were did u buy the gutter seal @?

I bought it at a hardware store near my house. It's an Ace hardware store though.

thread resurrection!......yeah im fairly certain this is what i have going on as well leaks coming from the firewall trickling down...ill remove the foam to try to narrow it down later but im thinking this is my issue

My 89 gets water on front floor as well. Pass side its seems. Not the heater core(I just replaced that). Clean water after heavy rains. It sounds that I may have same issue as yours. I just wasn't able to see inside where you put the sealer. Only place I saw was around your heater core hose nipples. Would you or anybody else for that matter have any picture of the cowl seam area you are talking about?

My leak ended up being the windshield. So give that a try as well

It was the drip rails on mine. I could see some cracks and a couple tiny holes in the seam sealer. When I dug out the seam sealer I found rust where water had made it past the sealer.

I had to deal with this on my 88 recently. I put it off for way too long. I didn't like the idea of trying to deal with all the spot welds (at the point where I had got to it I had already destroyed a few spot weld cutters and was tired of breaking things). I had the fenders off (had to replace the radiator support anyway) so I cut a larger hole at the ends of the cowl where the drains are. Removed the two access plates in the engine compartment and blew out the cowl with compressed air. Scrubbed a small wire brush on the seam as best as I could and blew it out again.

Using a popsicle stick and one taped on a long screwdriver, I applied Locktite PL S30 to the seam and smoothed it out as best I could. I should note that you will want to be careful applying this stuff, it goes on like tar and stays that way for hours, but once it dries, it seems to be virtually indestructible. I'll have to grab some pics at some point here, still have the truck tore apart.