Mystery hole on cowl on 48 DeSoto

[MarcDeSoto]

If you look at my 48 DeSoto cowl you can see three holes on the left.  I think I know that the holes on top of each other are for the hot water and return water for the heater.  But does anyone know what the hole on the left is for?  

 

 

[Marcel Backs]

The coil on my 1940 dodge mounts through the firewall in that location. It could be a pass-through for the ignition switch wire going to the coil. Does your ignition switch have a armored jacket protecting the hot wire to the coil?

[joecoozie]

I looked at my Chrysler and it looks like this:

The 2 that are diagonal to each other are the heater core feed/return hoses.

The 3rd one, almost in the middle of the firewall, is for a drain hose for the cowl vent.

[desoto1939]

same for my 39 Desoto with the three holes.

 

Rich Hartung

[MarcDeSoto]

Yes you guys are right.  I was wrong thinking the two holes on top of each other were for the heater.  But the one on top must be the hot water hose and the one on the far left must be the heater return hose.  So I'm thinking the heater valve at the back of the block must be the hot water supply, and the heater return hose must go to the water pump.  

[TodFitch]

Yes, the heater valve on the back of the head is the hot water supply to the heater. And the heater fitting on the water pump is the return. If you look at the design of the water pump you can see that the heater fitting is on the suction side pulling coolant into the pump.

[wagoneer]

The two upper are for the heater but the lower one seems to  be a vent for water that comes through the air vent or something. It’s a hose that is just left open at the end

 

[MarcDeSoto]

It looks like your heater hoses are reversed.  The hot water supply is coming from the water pump, and the return hoses are going to the hot water outlet at the back of the head.  Unless the hot water hoses go to the lower hole and the return water comes from the higher hole?  But maybe I'm missing something?  

[wagoneer]

12 hours ago, MarcDeSoto said:

It looks like your heater hoses are reversed.  The hot water supply is coming from the water pump, and the return hoses are going to the hot water outlet at the back of the head.  Unless the hot water hoses go to the lower hole and the return water comes from the higher hole?  But maybe I'm missing something?  

 

You are so right! Another surprise gift from my PO! As I go through, I find little things that are wrongly installed or just not quite right that once reconciled make a whole of sense . 
 

for example, I realized the oil bath support rod was mounted to the left spark plug cabling organiser instead of the right side . 
  Why does that matter, you may ask? Well, i always struggled with the oil bath being slightly pushed at an angle due to the way it was being secured. More important though is the oil bath holder also holds the throttle return spring attached to a little hook that now very neatly over the cabling holder instead of stretching it out as before causing a weak spring .

 

 

thank you @MarcDeSotothis probably explains why I get heat emanating from my heaters after the car is running for a while regardless of heater setting!

Edited July 17, 2022 by wagoneer