Help identifying water leak in cab

[hey its me]

My floor gets wet on the passenger side. 81' short bed c10. Initially I thought it was water leaking past the windshield, but today I pulled the kick panel off (where that vent/flap thing is) and poured water over the windshield. I saw the drip come from inside where the kick panel is, up above. I can't really see where it is, or how to get to it. I took a few pictures. I'll upload them soon. I don't really know what to do about this one. Any help would be appreciated.

Thanks- Ian

[hey its me]

Now, here is a picture where i stuck my phone in the vent/flap hole, pointing up taking a picture. This is where the water is coming from.

[chengny]

That plenum is for fresh air inlet (and fan recirc with A/C equipped trucks). The outside air is drawn in from under the cowling in front of the windshield.

Along with the incoming air, it is expected that - under certain circumstances (e.g. rainy days, melting snow, car washes, etc.) - some water will also flow down into the fresh air intake plenum. The plenum is designed to drain any water that flows into it. Probably what has happened is that the opening at the bottom is plugged up. It could be blocked by leaves, pine needles, rodent bedding, etc.

With nowhere to drain, the water that comes in with the fresh air collects in the bottom of the plenum. Eventually it reaches a level where it can flow over the lower lip of the damper opening and spill out on to the cab floor.

This shows the location of the drain at the plenum floor:




Try blowing the obstruction clear with compressed air (from the bottom up) or out through the bottom by reaching in through the fresh air inlet damper and poking it out with a thin rod. You could also try jamming a shop vac hose down there and vacuuming the debris out.

[hey its me]

Originally Posted by chengny

That plenum is for fresh air inlet (and fan recirc with A/C equipped trucks). The outside air is drawn in from under the cowling in front of the windshield.

Along with the incoming air, it is expected that - under certain circumstances (e.g. rainy days, melting snow, car washes, etc.) - some water will also flow down into the fresh air intake plenum. The plenum is designed to drain any water that flows into it. Probably what has happened is that the opening at the bottom is plugged up. It could be blocked by leaves, pine needles, rodent bedding, etc.

With nowhere to drain, the water that comes in with the fresh air collects in the bottom of the plenum. Eventually it reaches a level where it can flow over the lower lip of the damper opening and spill out on to the cab floor.

This shows the location of the drain at the plenum floor:




Try blowing the obstruction clear with compressed air (from the bottom up) or out through the bottom by reaching in through the fresh air inlet damper and poking it out with a thin rod. You could also try jamming a shop vac hose down there and vacuuming the debris out.

Ahhhh I see. The problem is that the water streams down the side of the kick panel in a way that goes directly into the cab, onto the carpet. Maybe it's the angle I park? I don't know. So there's no way to plug this hole? I don't have a/c anyways.

[chengny]

IDK - maybe try filling the fresh air intake opening with some of that "Great Stuff"?

[snaptoo]

The problem with filling it with foam is the wiper linkages ! I'm in the process of changing my 80 swb to a vintage air 1v unit , it doesn't use fresh air from the !cowl . I took a pattern from the plastic screen "factory" and had a piece of 18 Ga. paintloc sheetmetal laser cut as a block off !I used some urethane dum dum strips to seal it and drilled into the cowl in four places to hold it down.. It can be removed to service the wiper linkages .

[wideopen1967]

Thanks!!! This leak has been harrassing me forever!!!!!!

Originally Posted by chengny

That plenum is for fresh air inlet (and fan recirc with A/C equipped trucks). The outside air is drawn in from under the cowling in front of the windshield.

Along with the incoming air, it is expected that - under certain circumstances (e.g. rainy days, melting snow, car washes, etc.) - some water will also flow down into the fresh air intake plenum. The plenum is designed to drain any water that flows into it. Probably what has happened is that the opening at the bottom is plugged up. It could be blocked by leaves, pine needles, rodent bedding, etc.

With nowhere to drain, the water that comes in with the fresh air collects in the bottom of the plenum. Eventually it reaches a level where it can flow over the lower lip of the damper opening and spill out on to the cab floor.

This shows the location of the drain at the plenum floor:




Try blowing the obstruction clear with compressed air (from the bottom up) or out through the bottom by reaching in through the fresh air inlet damper and poking it out with a thin rod. You could also try jamming a shop vac hose down there and vacuuming the debris out.