What's the purpose of the cowl vent drain hole?

[central52]

I'm putting in a new gasket for the cowl vent on my 47 Plymouth. After taking off the unit, I noticed a drain hole and a hose underneath running out to the firewall.

Curious. If you close the cowl vent in rainy weather, or car wash, one would assume no water will come in. So, why is there a drain hole, if no water is going to come in anyhow

The only way would be for the vent to be open, and then, lots of rain water will come in the vent itself. This sure puzzles me. Ed Parauka

[John Mulders]

my guess is that there will be water coming through any way (eg when opening the vent and there is still some water left around).

Then that water would go out through the drain instead of into the cabin.

John

[Young Ed]

The cars equiped with fresh air heat have a drain hose. They are designed to be left open in rain so you can have fresh air defrost.

[TodFitch]

On my 1933 the cowl vent gasket leaks a little. There are two drain hoses (why two and not one I haven't a clue). If one or more hoses are missing you will get some water dribbling onto the floor if you drive in the rain.

Not sure why the cowl vent gasket does not seal well even with good new rubber. Maybe they could not put a strong enough hold down spring on the vent because then the vent would be hard to open and close.

[daddyo23]

The cars equiped with fresh air heat have a drain hose. They are designed to be left open in rain so you can have fresh air defrost.

I guess I have fresh air defrost. Probably should put a hose on there.

Thanks for the info.

[Young Ed]

Wayne does your car have the fresh air system? I'd like to see how the bottom door looks with the proper gasket. Mine is missing and the door hinges were rotted off. Think I got the hinges sorted out but I still need a gasket of some sort.

[steveplym]

I didn't have a hose on mine for a long time and wondered why water leaked on the floor. Once I found this forum I learned of the drain on the vent. Last summer I put a clear hose on it and ran it out to the original bracket on the firewall.

No more leaks on the floor and when I wash the car there is always water draining out the hose. So it does work.

[daddyo23]

Wayne does your car have the fresh air system? I'd like to see how the bottom door looks with the proper gasket. Mine is missing and the door hinges were rotted off. Think I got the hinges sorted out but I still need a gasket of some sort.

Not sure. I have a tube coming out the front of the firewall, that's all I know. I'll try to get a picture and post. Wayne P.

[Plymouthy Adams]

By design the vent is covering an opening..this opening is curved to be level with the cowl with the seal fitting in the depressed area about the opening..the idea is to keep the water out of the car....which the seal does when the lid is closed..also note the air gap about the lid and the opening in the cowl when shut..even though the gasket is there..this position is just to POSITION the seal..ie any water about this seal will find its way to the drain tube and with a good hose out the front of the firewall thus not dripping on the interior floor..

As for your hinges..they are part of the welded section to the dash on one part and integral with the pop up lid/grille assembly on the other..IF you ever find these are rusted shut, common, the tack welds are not super heavy and suggest that the rust bond be broken by heating red..I had to apply cherry red heat and lube twice on my 51 to free it..this car has sat since 1966

If you break the welds this will be a major pain to fix...

[daddyo23]

About the '51. THAT had a tube out the front. These nights are making me strange®. Tim is right. I had to heat those screws to beet red to get the hinge to move.

[Plymouthy Adams]

That is why I said "with a good tube out the firewall.." as the P15 does exit much lower by way of rubber tube. Keep in mind that if you should modify your dash by installing later model radio and such..be sure the fresh air vent if left open in inclimate weather will not drip on the radio...this was the reason for the back side being a single cover with the original radios. Flap of rubber over the modern stuff will divert direct moisture contact...

[daddyo23]

Ed,

Here's the heater I have, and the hose in the firewall

[Young Ed]

Wayne do you have the fresh air setup in the middle though? My car had a giant extra contraption in the middle to allow fresh air to go to the heaters. Then there is a second lever that opens a door if you want the cowl vent to allow air into the passenger compartment. I'm trying to find what the gasket for that second door looks like.

[daddyo23]

No, I don't believe I do.

[David Mac]

dodgePU.

I have the same box but no gasket. I am trying to figure out how the lever connects to the door. It has been so long ago that I took it apart I don't remember and of course I didn't tkae notes on this assembly. Does any one have a drawing or picture of the proper connection of the lever to the fresh air box door?

Thanks,

David Mac

[Don Coatney]

Does this help?

[Young Ed]

I will take a picture of mine tonight. I think I left it together enough that it will show at least how that part goes together. The part that confuses me is the hole is so much bigger then the door that the gasket must be quite big. And my hinges rusted off and had to be repaired so I don't know if that door should be centered or lined up with the top or bottom or ???

[David Mac]

Thanks Don:

However, I was talking about the fresh air box lever. The box that sits below the cowl vent and funnels air to the heater. It has a small hinged door to allow the flow to the heater or directly into the car.

Thanks DodgePU

If you could get some pictures that would be great.

Thanks,

David Mac

[Jim Yergin]

Ed,

Is this the grommet you are looking for?

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&_trkparms=tab%3DWatching&viewitem=&item=300038935052&_trksid=p3907.m32

Jim Yergin

[Young Ed]

Nope that ones further up on the fresh air device. The rod that pushes open the cowl vent goes through that to seal it.

[Jim Yergin]

Do these pictures help?

Jim Yergin

[Young Ed]

Jim those do help. The seal around that rectangle door is what i need to try and create.

[David Mac]

Thanks Jim:

They say a picture is worth 1000 words. That is exactly what I needed to hook up the lever properly. I too have to solve the Gasket for the door, so DodgePU if you figure it out let me know and vice versa.

Thanks again

David Mac