did anyone ever post any photos of the fix with drilling the hole in the heater obx?

 

Sorry for the late response/s!! I have not been on here as much lately. I have yet to have anymore water in the cab since the drain hole was put in the bottom of the heater box. The fix is simple and you can probably accomplish it without pics but if needed I can still try to get a few since I was a slacker and didn't get them posted before. If you look under the hood at the blower/heater box plenum area then you can get a good idea where to look from underneath. With a few bolts out you can pull back the passenger side fender liner enough to access the bottom of the box to get a drill in there. The hole I put in was not much bigger than a No.2 pencil but yet it will drain any water sufficiently. I drilled it at the lowest point in the middle of the bottom of the black heater box. Look at it and if you are not sure reply back and I will try to post pics again. If needed pm me and I can get you my number if you want to call.

Jerry

 

thanks for the detail. i'm going to wait & see right now. My pasenger side sunroof drain was plugges. This may have been the source. If no more water appears, it was the sunroof. If the water comes back, i will check the heater box.

 

Hey guys I realize this is a way old thread, but we have had a lot of rain over the last week, at least 11"... and my '03 truck is leaking bad. Definitely leaking from the fresh air intake... I pulled the carpet up, looked around very carefully under the dash to find the source, and it is definitely in the blower motor housing.

I fired the truck up, turned the Heater-A/C control to Max A/C (I habitually turn the control to 'off' before shutting the truck off, or letting it run on the Turbo Timer) and watched the fresh air flap close. I then turned the control to off, watched the flap open, and I could see the lower portion of the seal was wet. I then stuck a length of vacuum tubing in through the open door and siphoned out at least a quart of rain water.

I don't know if there is a drain somewhere that I can't see, but I am definitely contemplating drilling an auxiliary drain like fleastang did.

Are there any Ford Techs out there who can say for sure why this happens?

I am assuming the fresh air intake sill on the drivers side fill with rain water quickly when it is raining hard, and the water ends up on the passenger side.

Just as info, my truck was parked for a week straight during the rain, with the front end down slightly, and the right side down slightly as well. This allowed all the rain water to collect on the right side of the truck.

Thanks for the input fleastang, you hit the nail on the head on this one.

 

Dried my truck out completely, removed the two lower 5.5. mm screws, the lower 8mm screw, and the two plastic push in retainers from the the bottom of the right inner fender well, used a 15" long 1/4" bit to drill a drain hole in the lowest portion of the blower motor housing, directly in front of the vacuum hose grommet that is directly under the 'grate' that fleastang describes. This should cure it.

While I was at it I looked up the TSB regarding silicone caulking the pinchweld behind the upper door weatherstrip seal as well, and sealed all the gaps. If anyone is getting water in the cab from up high and DOES NOT have a sunroof or clearance lights, this is worth looking into. I can't believe the dealers are unaware of the HVAC leak problem.

 

Any one solve this issue? A while back I added a cheap EBAY third brake light to my truck which had a cheap seal which I was afraid would not seal but I installed it anyway. A few months later I found the issue with water in my heater box when the truck was facing down hill so I removed the light and reinstalled the factory third brake light but have recently noticed I still have the issue.. I am now debating on ordering a new third brake light but would like to know if any of you had this issue before wasting any money..

 

my problem was a clogged sunroof drain...not sure I can help you with your problem.

 

I was wondering if this heater box drain really did the trick? I have a 2000 f 250 Super Duty with the same problem now for years. I don't have cab lights and I don't have a sunroof and the water comes from under the dash after heavy rain. I was considering changing the windshield wondering if it was leaking and being eleven years old probably would be an improvement. I know this is an older thread but would appreciate the help..Thanks.

 

put the new recon third brake light in today in hopes it fixes my problem.. Fingers crossed.

 

The recon light seems to have fixed my problem! It has been several months now and I have had no issues with water getting into the air box!

 

As a follow up, I still do not have any water getting in the truck after the hole being drilled in the air plenum/box and we just had flooding rain of about 6" in 2 hours. As a precaution I still leave my heater control to floor when I leave the truck just to keep the interior "flap" shut on the plenum box. This mod has been done a few years now with no problems.

 

Rep points sent your way for reporting back

 

My truck has been in some fairly serious rain storms since the hole was drilled in the heater box, and I haven't found a drip since.

 

Went to the in-laws over labor day weekend, wife looks at me and says "Your trucks peeing on me."

About 90 degrees, no rain while driving, some rain the night before, but was running the AC for the whole 30 mile trip, and it only leaked during part of it.

With the user reports of leaky windshields, old cab light seals, blower box design flaws, and maybe a plugged AC condensate drain hole... I've got some work to do.

Also thanks Fleastang and SoCal for reporting back about this.

 

i think it comes down off the windshield where the cowl cover meets the windshield and runs across the underside of the plastic cowl cover and then drips/leaks down directly into the fresh air vent for the fan box and thus into the bottom of the box.
it has to be a torrential rain so that enough water gets in to fill up the box and overflow into the cab.