Not sure if this is part of the design but water was ejecting from a small port to the right (driver's side) and slightly lower than the hole pictured. (which I think is the flywheel cover?)
The radiator level has remained the same the last couple times this happened - which curiously have been after a rain?
I searched for overflow discharge ports but did not get results to explain. Looking in the online shop manual I'm not coming up with anything either.
There is a drain for the cowl vent at the rear of the engine. If the level in the radiator has not gone down I would think that is where the water is coming from.
There was a short black rubber hose that was/is connected to the metal drain tube. That drain hose usually directed water onto the valve cover (or/and down rear passenger side of the block).
A silly design because, if directed incorrectly, the water could go onto the top of the valve cover and then enter openings in the (1954 and earlier) valve cover. Water would then drip/drain over the inside of the head.
Do you have that drain hose?
I used a plastic tubing connector to add a longer length of hose down the passenger side of the block. THe hose is long enough to empty beneath the oil pan.
Place a pan under the vehicle in the area that you saw the puddle so next time it rains, you’ll be able to capture some of the fluid. You’ll should be able to distinguish if it’s anti freeze or water.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
Oh sorry. I meant that in looking through the shop manual linked above I cannot find a description of the port from which this water was ejecting. But I'll keep looking. Thanks Rog
Here is the drain tube shown in the Factory Assembly Manual.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
I would do as mentioned above and extend the drain down past the bell housing to exit under the engine. Since there's no change in coolant level it's unlikely the cause is anything other than the cowl drain doing it's job.