Floor board damp

[jjb]

Hi all. I have a 1999 e350.

I'm not sure when this started, but I recently noticed that the floorboard under both the driver and passenger is damp under the floor matt. When we did our build, we replaced that original backing and floor matts with an automotive backing and the vinyl coin flooring.

We are in the PNW, so it is quite humid. The van is driven every couple of months, so this isn't condensation from living in the camper.

I'm hoping someone can provide some guidance on typical leak points. We do have a fiberine camper top, which blocks the top of the windshield from heavy rains.

[posplayr]

Does "damp" mean water and not coolant?

[86Scotty]

Originally Posted by posplayr

Does "damp" mean water and not coolant?

Agreed, double check. Could easily be a heater core leak.

If not that it is likely from the top corners of the windshield. Common leak area, doesn't really matter which top is on the van, or whether you have one at all. If I recall, JWA did some research on this?

[posplayr]

Originally Posted by 86Scotty

Agreed, double check. Could easily be a heater core leak.

And for the 1997 E-350 at least, you don't have to remove the dash to replace the heater core .

Ask me how I know.

[1der]

Check this link:
https://www.sportsmobileforum.com/fo...mat-19604.html

pinch seams under dash are, in some cases, a culprit.

[antmanbee]

I think that seam on the drivers side is where mine is leaking on my 2001 e350.
I have the floor mat and all the plastic pieces removed and it looks like that seam is damp, but not anywhere up higher. I am going to caulk it.
I was wondering if I should look into the engine side on the firewall or maybe under the cowling to see if some water is puddling where it shouldn't be.
I'm not getting any water on the passenger side.
There was just a big storm that dumped several inches of rain with high winds a couple of days ago and at least all my back windows had no leaks. I have just finished removing them all and redoing the butyl tape to reseal them. So I am happy about that. Just this one last leak to solve for the drivers floor area.

[JWA]

Originally Posted by posplayr

And for the 1997 E-350 at least, you don't have to remove the dash to replace the heater core .

Ask me how I know.

That is true, I've replaced my 2000 E250 w/5.4 engine's heater core some years ago. Since things were already apart the blend door and actuator motor also replaced with Dorman parts found on eBay.

Typically a heater core leak will show itself on top of the floor coverings. Does this suspected leaking van have the original factory floor covering in place? Does the noticeable moisture extend rearward at least as far back as the front seats?

Does the rear cargo area have those same factory mats still in place, are they wet as well?

[mgmetalworks]

Somewhere on this forum I posted about a leak I had on my van that caused a damp floor but was difficult to trace to the source. When I had the body off of the frame for the Cummins swap I discovered a poorly sealed seam between all of the pieces that make up the doghouse, lower floor and firewall.



The seam between the lower vertical section of firewall and the floor will trap water if not sealed correctly then the water seeps down between the doghouse section and front floor panel...exiting at the junction marked in the picture. The seams on both sides of my van looked like the robot at the factory missed its mark. I had to dig out the poorly applied sealer and redo it all.

[jjb]

Thanks all.

The heater core was replaced a year ago, after failing in Perú and me needing to bypass it for a year. [emoji15]

As the moisture is primarily on the driver's side and under the mats, I am pretty sure the new core is not leaking.

It looks like I am going to need to pull out the flooring and spend time soaking the van with a hose to determine the exact leak spot.

Your comments have helped me realize that I am not crazy, and likely have an actual leak.

Thank you!

[1der]

Before soaking w a hose -

At night place a bright light in the engine bay and also under the cowling forward of the windshield. Go inside the van and look around the pinch seams for light "leaks". Far easier place to start.