wd45 cooling problems

the reason it was steaming was because of a crack. i just assumed that the steam meant it was overheating. the temperature gauge needle was in the red at 220 degrees 

Hunter- some basic physics things you need to keep in mind:

Your modern automobile or truck runs in what's called a 'pressurized' system, meaning, the coolant is absorbing heat from the engine, so it's temperature rises.  With temperature rise, two things happen- first, the liquid expands a little, and second,  As the temperature rises, the 'vapor pressure' of the liquid changes, and evaporation accellerates.  Both of these cause the gaseous volume inside the cooling system to decrease, which means pressure inside is rising. 

There's a point in liquid heating and vapor-pressure curves where the liquid wants to become a gas... but it's not just all about heat, it's about heat and pressure.  Add more pressure, and the boiling point rises.

In the case of a can of water on the stove, at Iowa altitude, you can put a thermometer in that water (but don't let it touch the can) and start heating the water.  As it warms, you'll see a little steam start wisping off... that's evaporation...  and eventually, you'll see bubbles form, and a little while later, you'll see it boil.  At each point, you'll see the temperature of the water rise...  but the you'll hit 212F, water will be in full boil.  At that point, you can turn up the heat of the stove as high as you want, it will boil more aggresively, but that water will NOT rise above 212F... because it is amidst phase change... water, at atmospheric pressure of 800ft ASL or so, will exist as liquid form from 32F to 212F only.  Below that, it's solid (ice) and above that, it's steam.

Standard atmospheric pressure is about 14psi.  If you were to close up that can, and pressurize it by say... 5psi... the boiling point would go up to 226.8F.

Likewise, coolant in an engine with a sealed cooling system and a 5psi radiator cap, will never exceed 226.8... as long as there's water in that system.  If you ever find yourself around a running water-hopper hit-and-miss, dip a thermometer in the hopper, you'll see that the water is always no warmer than 212.  As long as you keep putting liquid water IN, the engine will NEVER overheat.

Here's a good calc:  https://www.calctool.org/thermodynamics/boiling-point

In the cooling system, the liquid's temperature rises to a point where the liquid starts 'phase change'... meaning, it's boiling, and as it does that, pressure in the system comes up.  Eventually, the closed system's pressure will, by virtue of that phase change curve, rise to the point where the graphed lines of developed pressure, in the system, and the temperature in the system, match, and that's where your system pressure and temperature will BE.

The 'gotcha', is that if you have a leak, it 1) won't hold pressure and 2) the volume of water is decreasing, thus the available volume for gases is increasing... so it throws everything for a loop.

The crack in the radiator isn't an unusual thing, it happens to all of us more often than we'd like to admit... but until you get that fixed, and then do a pressure test (for a leaking head gasket, water pump, hose, etc), you won't have a stable system.  You'll also get crazy antics out of engines that might not be leaking COOLANT out, but combustion gases (from the combustion chambers into the water jacket) are 'falsely pressurizing' the cooling system.

There are clever ways to determine all these things... the combustion pressure leak is one of my favorites-  start it up cold, with the cap off, and once it's running and warming, look into the radiator.  If you see it sending bubbles up long after it's been started, you got a combustion gases leak.  The biggest problem with combustion leaks, is that the combustion gas bubbles can accumulate at high spots in the head, and with a gas bubble in there, the transfer of heat is prevented, so you'll get 'hot spots'.  Allis heads aren't very susceptible to hot spotting from bubbles... but the Ford Industrial 192 four in my Hyster forklift WAS... until I did a cooling mod that prevents bubbles from accumulating.

As for your radiator, the guy my local buddies all recommend, is Bill's Radiator & Automotive on 11th St in DeWitt.  I think Jerrod is the name they've mentioned, but they're a recommended go-to for all radiators antiquish.

i was wondering would the radiator from a wd work for my wd45

i thought they looked simmilar thanks