That port hole is probably a freeze plug, and if anything but 50-50 coolant mix was run it it you may have a rust hole in it.
Not too difficult of a job to do replacing it, the work comes in what you have to remove to get to it.
An antifreeze leak.An antifreeze leak.
Sounds like a leak in the heater core.
There may be a hole in the radiator?
You have a corroded core plug (sometimes called a freeze plug)
The leak would vary on the size of the hole or seal failure.
Most likely cause is the intake manifold gasket-antifreeze will usually leak down the back of the engine and drip off of the starter or somewhere in that area.
It will leak from behind the pulley that runs the water pump. There is also a small hole in the bottom of the the pump case for that very reason. If the shaft seal goes antifreeze will weep from the hole.
yes if there is hole in the diesel tank in motor
Antifreeze if you get an internal leak in your engine it could ruin the motor
chances are you have a cracked heater coil
Low on antifreeze/antifreeze leak...loosenut... www.ceriousproductions.com
A leak.