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'Bolter
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My project truck is a '40 cab on a '41-'46 chassis.

There were no usable wires in the project when I received it and I have not been able to locate a diagram of what goes through the firewall at what location. (I may have not looked in the correct place!)

I have a grommet kit and am starting to set things up, but I am wondering what is supposed to go through the firewall at the location circled in the attached photo. (The other photo shows the condition of the few wires that were on the project when I received it.)

Thanks!
Attachments
Original Wiring....JPG (199.88 KB, 161 downloads)


Nick
1940 KC Model 1/2 Ton Pickup Project
(with '37-'39 Bed and what we think is a '42-'46 Frame)
Taos, New Mexico
Joined: Feb 2008
Posts: 1,124
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Nick
I guess it might be a drain for the cowl vent?

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'Bolter
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I vote cowl vent drain too.


~ John in Utah
1946 1/2Ton w/4-speed manual transmission w/1960 235 engine
Here We Go
Follow in his DITY Bay

- If you think about it, it has been one year ago today!
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With your fingers, feel up behind that metal deflector to see if there is a hole from the cowl vent. Looks like it deflects the water from splashing straight down onto the motor.


Craig

My '50 Chevy 3100 5 window, '62-235cu, 3:55 rear
My truck ....... Respect The Rust
If I'm not working on my truck, '65 m00stang or VW camper, I'm fishing with the wife or smoking Salmon.
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Yes, all!

I believe that is it!

With that in consideration, I searched online and found that both Classic Industries and that Classy Chev both claim to have a bit of hose that would fit the application.

When I looked up under the dash I saw a bit of metal tubing coming off the underside of the cowl vent area that pointed directly at the hole through the firewall that is behind that metal deflector visible just above the valve cover (circled in the photo in the original post).

It looks as though the design is for the water to go from the cowl vent drain into a piece of hose through the firewall and then drip down the drivers side of the engine.

I have attached a photo that shows the alignment of the cowl vent drain deflector (my term for it) over the driver's side of the engine. I am not going to stress about it too much, but it seems surprising that the design doesn't have the hose carry the water farther down toward the ground.
Attachments


Nick
1940 KC Model 1/2 Ton Pickup Project
(with '37-'39 Bed and what we think is a '42-'46 Frame)
Taos, New Mexico
Joined: Nov 2021
Posts: 1,405
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'Bolter
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The later model years have a hose for the cowl drain but do not have the deflector. I guess they decided that it did not matter where the drain exit was. Neither case has the drain extended down enough to keep the drain water from being released onto the engine.


1949/50 3600 Project
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Barry Weeks could've answered this ... frown


~ John

A kid raised on Hotwheels, Matchbox and Tonka cannot be reasonably expected to own only one vehicle as an adult.

1949 Chevrolet 3804
In the Legacy Gallery | In the Gallery Forum
1973 IH 1310 Dump
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2001 International/AmTran RE3000 "Skoolie"
2014 Ford E-350 4x4 (Quigley)
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When I first asked myself this question (months ago), I figured that it was so basic and the answer must be so obvious, that I was hesitant to ask it on Stovebolt.

Now that I have asked it, I want to say that I appreciate the fact that I can ask basic questions here and not be embarrassed by my lack of knowledge or experience.

Thank you all!


Nick
1940 KC Model 1/2 Ton Pickup Project
(with '37-'39 Bed and what we think is a '42-'46 Frame)
Taos, New Mexico
Joined: Mar 2024
Posts: 386
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John,

With regard to Barry Weeks, he was gone before I arrived on the Stovebolt scene and before I found my project...But I have read several things he wrote and I learned a lot just by studying the photographs of the items in the auction of his collection. He has had a strong, positive impact on my participation in the hobby even though he is no longer physically here.

Barry's wife, Kathy, also made a strong, positive impression of this group and the hobby after Peggy suggested I contact her about the possibility of shipping some items from the auction.

Last edited by Nick in Manitou; 12/01/2025 4:48 PM. Reason: spelling correction

Nick
1940 KC Model 1/2 Ton Pickup Project
(with '37-'39 Bed and what we think is a '42-'46 Frame)
Taos, New Mexico
Joined: Feb 2004
Posts: 29,881
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It's entirely possible that the engineering crew took into account the air blast from the fan and/or the forward motion of the vehicle that would blow any drainage back toward the firewall. That deflector probably came into play when the vehicle wasn't running, or moving down the road. Early valve covers had ventilating slots in them, and water dripping onto the engine could end up in the oil pan.
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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I just installed a new gasket and I'm not sure how much water will be getting in as long as I don't drive in a rain storm with the cowl vent open.
Attachments
IMG_1235a.jpg (123.73 KB, 78 downloads)


~ John in Utah
1946 1/2Ton w/4-speed manual transmission w/1960 235 engine
Here We Go
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- If you think about it, it has been one year ago today!
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I placed an order with The Filling Station for several parts to get me closer to starting the engine in this project (with temporary wiring).

Along with that order I splurged and spent $2.50 for a, "1933-46 TRUCK COWL VENT DRAIN HOSE".

When it gets here, I will install it and post a photo.


Nick
1940 KC Model 1/2 Ton Pickup Project
(with '37-'39 Bed and what we think is a '42-'46 Frame)
Taos, New Mexico
Joined: Mar 2024
Posts: 386
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'Bolter
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John,

Somehow, keeping the cowl vent closed when driving in a rain storm does seem to be a sensible way to go!


Nick
1940 KC Model 1/2 Ton Pickup Project
(with '37-'39 Bed and what we think is a '42-'46 Frame)
Taos, New Mexico
Joined: Oct 2021
Posts: 6,965
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'Bolter
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I just cut a length of heater hose I had laying around for the drain hose. I should have made it a little longer than stock.


1950 Chevrolet 3100 (Ol' Roy)

1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
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Originally Posted by Nick in Manitou
,,, I splurged and spent $2.50 for a, "1933-46 TRUCK COWL VENT DRAIN HOSE".

When it gets here, I will install it and post a photo.

I did the same. I struggled a little to get the hose installed, but added some lubricant to the hose and fitting and it slide right on.


~ John in Utah
1946 1/2Ton w/4-speed manual transmission w/1960 235 engine
Here We Go
Follow in his DITY Bay

- If you think about it, it has been one year ago today!
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I purchased the Cowl Vent Drain hose that The Filling Station listed as being for 1933-'46. It didn't cost much at $2.50, but in the end, I was disappointed.

I assumed that the hose would be the correct size for just fitting through the hole in the firewall...and it was, but I also assumed that it would be the correct size to fit the metal tube that is connected to the underside of the cowl vent opening...and it wasn't. Even with liquid dish soap, effort, and with carving out the end with a razor knife to put sort of a flair on the inside of the rubber hose - I couldn't force it to fit.

I ended up cutting a slit in the rubber hose and slid it onto the metal tube with the slit at the top with the idea that, since the water coming into the tube wouldn't be under pressure, it would probably not drip out of the slit. Only time will tell.

I have attached photos of what I received and the final installation.
Attachments
From Filling Station, CV-381A.JPG (163.22 KB, 44 downloads)
IMG_9533.JPG (372.69 KB, 44 downloads)
IMG_9534.JPG (120.09 KB, 43 downloads)
IMG_9544.JPG (288.02 KB, 43 downloads)
IMG_9545.JPG (271.32 KB, 43 downloads)
Cowel Vent Drain Installed.JPG (235.36 KB, 44 downloads)


Nick
1940 KC Model 1/2 Ton Pickup Project
(with '37-'39 Bed and what we think is a '42-'46 Frame)
Taos, New Mexico
Joined: Feb 2005
Posts: 1,685
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'Bolter
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Mine was snug enough that I didn't need a hose clamp. It was tuff getting it to slide on though.
Attachments
IMG_1153a.jpg (61.77 KB, 32 downloads)


~ John in Utah
1946 1/2Ton w/4-speed manual transmission w/1960 235 engine
Here We Go
Follow in his DITY Bay

- If you think about it, it has been one year ago today!

Moderated by  Phak1, Woogeroo 

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