Passenger floor board leak FIX

It's been raining a lot here in Honolulu and my half assed attempt in Nov has proven utter failure. My Passenger side carpet is almost completely saturated. After the whole cowl endeavor, I'm wondering if it would be more effective to seal from the inside. Has anyone removed their dash to seal the leak? I've been trying to find write ups on dash / instrument panel removal but the one on custom tacos is a 404 error

My hopes is to take out the dash to get the leaks and clean up some rust on the floor boards.

 

I would suspect going from that direction may be more difficult than from the engine bay/cowl. There will be a lot to work around like the heater core, air bag, and air vents. I have never been that deep in the dash though so let us know how it works out!

 

Thank OP for shining a light on this problem. Pictures always make a difference.

 

I can see you were able to remove the fender and not destroy the antenna. My antenna mount is rusted, so I can't turn the top part to unscrew it. Using normal antenna removal techniques, it just crumbled on me. The only way I can think of separating it from the fender is to use a Dremel tool to cut it off.

 

Thank you for this thread. I started down the road to repair this afternoon. Not to thread hijack, but here are some pictures from today's work below.

To remove the fender, you need to pull out the piece of trim that is under the headlights. The trim snaps into a plastic holder that is to the right of the bolt hole.



To remove (and reinstall) the two bolts that are behind the bumper, you can loosen the bumper so you can move it down and out of the way for a 10mm socket.



Here's a picture of the front after the bumper has been removed.



Here's where I stopped for tonight. I'll pick it up tomorrow morning. You can see where I had to cut the antenna coax cable to remove the fender.

 

Good lord, wth is the windhshield cowl for if its sealed up like that?

 

I removed everything and found the wettest spot is this small piece of carpet pad that I pulled down to make this picture. It is still wet from the rain that occurred last week. I've kept the cab covered with a tarp since I found the leak. I'm testing for a leak today by spraying brake parts cleaner in the wiper arm area. Brake parts cleaner is cleaning up the area. If it leaks into the cab, I can smell it in addition to seeing a wet spot. So far, no luck with any moisture going into the cab.



You can see the cleaner dripping from the cowl vent. It drips from this vent, but does not enter the cab. I'm starting to get stumped.

 

Ok.. I was able to recreate the leak by placing the water hose in the wiper arm tray. Pictures below. Now I need to let it dry out and try some sealer.

Water hose location.



Water running out of the vent hole.



Water running down into the passenger compartment.

 

Last update for today. I ordered a fluid film spray tube to use with Flex Seal Spray Rubber Sealant Coating in the picture below. I bought this at Lowe's in the roofing material department.



I cut off the metal spray tip so I could use the tube to dispense the sealant.



This stuff is messy, but I like the way it flows into the seam cracks. It will take 24 hours to dry. I may give it another coat tomorrow.

Pictures

 

The leak has been FIXED! Thank you @TacosConQueso

It took 3 days, but it was well worth it.

Day 1 - Remove fender, remove cowl cover and wiper assembly, clean the cowl area with brake parts cleaner. Use water to flush out the cowl and recreate the leak. Spray in 1st coat of Rubber Flex Sealer and let it dry for 24 hours.

Day 2 - Spray in 2nd coat of Rubber Flex Sealer -- let it dry for 24 hours.

Day 3 - Test for a leak. Reinstall fender, wiper assembly, cowl cover, and anything else removed during the process.

I like the idea the rubber flex product is very fluid and easily runs during the application process. It seeps into the cracks where water travels into the cab. The second coat will further protect the 1st coat and catch any remaining openings that would cause a leak.

Pictures

Water running from the cowl drain during testing. I put the water hose inside the cowl drain area from the driver's side let it run for 15 minutes.



Inside the cab during the water test. NO LEAKS!

 

Way to tackle this! I've debated the flex seal route and seeing this inspired confidence. I'm going to give this another go.

 

@CS_AR how did you take care of the passenger side corner? Did you just run the fluid film nozzle blind? Or did you find a way to apply it precisely?

 

I used a wand with the spray tube and had to guess at where the leak location. Apparently not precisely enough.

No leaks when I sprayed it with a water hose.

But after last night's thunderstorms, there is still a small amount of water that ran down the corner seam. This took care of 90% of the leak. But not 100% It feels like the leak is coming from just above the grommet where the wiring harness enters the cab. This exercise is telling me that there are two different leak locations. I took care of the big leak by sealing the seam. But a smaller leak persists.

In looking at the attached PDF document, I suspect the problem is coming from the verticle joint "in the corner" in Step 16. I don't recall spending time on Step 16. I think this is where I missed the mark.

Since the leak has slowed significantly and I have a lot of other projects with the truck going right now, it may be June before I can get back into. I will keep working at it until I find a solution. It may require me pulling the dash to find it.

The frustration is coming from not being able to recreate the leak with a water hose, yet a storm brings out the leak.

And to make matters worse here at the homestead, these same storms brought out a roof leak. So I'm working with a roofer to get a new roof. When it rains it pours.

I may need to get out the pressure washer on the 2nd round to find this final leak.

1st Round Assessment:

1) I have been dealing with multiple leaks. Sealing the seam across the cowl seam stopped the largest area. There is a smaller leak that runs down the seam that appears ion the corner where the kick panel meets the carpet. I initially thought the water was coming from the antenna grommet since it was loose. However, I replaced the antenna and the grommet and it is tight. No water appeared from this area this morning.

2) I need to spend more time sealing the area referenced in item #16 in the TSB.

3) I should have used my pressure washer instead of a garden hose to find the test the leak fix. While there are now only a few drops of water, the leak appears after multiple hours of exposure. I need a way to accelerate the test soak.

 

Understood. Indeed, when it rains, it pours. I'll remember that seam. Thanks for taking the time to reply! I hope the roofing job is easy.

 

This is the same location the mid 1980s Chrysler cars had, and why so many have rotten floors. Their solution was just to seal the important parts in a plastic bag. Nice write up, OP.

 

Rain Update:

Last week it rained for an hour in the afternoon. No leaks.

It rained all last night with some thunderstorms. I went out and checked it this morning in the rain. I got soaked but it was dry. We are in for 10 days of rain and thunderstorms. I will keep monitoring it in the meantime.

 

Great News! After reading your updates I took a stab at my leak repair. I ended up taking the whole dash out only to realize that I'd have to remove the evap core, blower assmb, and other stuff I rather not touch. So I took off the hood, cowl, and fender and attempted the tsb again but with Seam Sealer from the auto parts store and a larger ID hose. I relined the seam but once I got to the passenger side I realized I couldn't get to the corner again....So I released a big dollop of sealer a deep as I could, reached in elbow deep and used my fingers to spread it in the seam. I managed to get to the corner but It was all by touch.

With the fender removed I also seamed the seal near the rain gutter and cowl drainage. you gotta run a hose through the cowl drainage hole.

It's rained a little bit and my passenger floor is dry! I'm waiting for a heavy rain to see if it worked and then drink a sixer in celebration.

 

Good News. Which hole did you reach into?

It kept raining today and I found another leak this time more toward the center. I caught this leak running down the left side of the passenger floorboard. This is closer to the transmission hump.

 

I ran it up the hole that cowl drains out of while peering through one of the small holes lol.

I forgot to mention in my post that I also sealed up the Engine Wiring Harness grommet. Like you've noticed, my leak ran down the center of the passenger floor pan and when the dash was out, very close to the engine wiring harness grommet. When I removed the wiring harness grommet the bottom seal of the thing was boogered up and not sealing. I applied a healthy amount of seam sealer all around the inner and outer folds of the grommet. This may have contributed to the leak.

 

I think I need to go after the wiring harness grommet and something to the left.

I have a pressure washer that dispenses soap concentrate from jug or bucket. I'm thinking about mixing up some yellow food coloring and spraying it so I can use it as a dye trace. Then wash it off later.