Radiator Level Over Time

Yes my belt is on tight, and seems to be getting tighter as I age.

 

At this point I don’t know the brand, etc. I got it from Walcks. As for block, newly rebuilt motor with 2,000 miles. Radiator, brand new core just done 2 years ago. Heater not installed yet, another project on the burner. During cooler weather and at slower speeds, things are at 190-200 based in the laser.

 

I'm saying the critical parameter anywhere on earth is that the coolant should be hot but not boiling. Slight variations are acceptable. Even inevitable depending on the load, air speed, weather, fuel, etc.

There is a reason that OEM temperature gauges are not marked in degrees. It's not necessary.

 

I suggest dumping the 7psi cap in favor of a 4psi cap. Seven is too high for this motor.

 

And what benefit would that have ?

 

Why? The difference between the two caps is that the 7psi cap raises the boiling point within the cooling system by approximately 9°F above the 4psi cap. That in itself has nothing to do with the engine operating temperature. Your thermostat does that.

 

Difference is a 7psi cap pressurizes the system 75% higher than a 4psi cap. Whether this additional pressure matters to the cooling system, I don't know. One could imagine the additional pressure stressing the radiator or gasket sealing or something. Description of some specific vulnerabilities would be welcome.

If you run a 160F thermostat, and the temperature stays there, the operating pressure and boiling point of the system should not matter. I expect, in general, you want to avoid boiling because the coolant needs to stay liquid in order to conduct heat from the cylinders to the cooling air. Pockets of vapor in the block would be bad. If you don't need that extra headroom of coolant temperature, the pressure above the coolant would not seem to matter.

 

I understand your comments but the question is per scoutpilot, "Seven is too high for this motor.". My question is, why is 7psi to high for this this engine?

 

Willys own manuals state 7.

 

Perhaps, as timgr hinted, it may aggravate any slight leaks.

Keeping in mind, that is the temperature as found at the thermostat. It may certainly run higher at other parts of the block's water jacket.

I have found that an F-head can boil in extreme cold weather, because the thermostat doesn't open if it is rated too high.

 

I understand everything people have said. My question is addressed to "scoutpilot" as to why he believes, "Seven is too high for this motor." What impact does the 7psi cap have as apposed to the 4psi cap to this engine?

 

It doesn't. Had the radiator shop convert my F4 radiator from big cap to smaller cap.
Ran the F4 with that for 3 years; that same radiator now cools the V6 in my Jeep.

 

My dauntless is all stock. I use a 13 psi cap. It is the 22 inch radiator with shroud and 6 blade flex fan (not stock). If I flll the radiator all the way to the top, it will loose water down to just above the tubes and stays there. I used to top it off, but it always went back down. The FSM says that is normal. I have an analogy gauge and run at about 180 °. I have a 185° thermostat. I quit chasing g the level and monitor the gauge. The shroud makes a lot of difference.

 

Saw this in a search for something else. I know it’s for the older MB's but interesting and expensive. MB GPW Willys Ford WWII Jeep G503 Desert Cooling Kit | eBay

 

I was always just allowing the radiator to seek its own level, usually about 3" below full. I wedged in a temporary fluid reservoir (old antifreeze jug) next to the rad and ran the overflow hose into it. Now I seem to stay full and no more mess. It always stays cool, with or without the reservoir and an 80s regal radiator so I can't comment on temp. I should really grab an actual overflow tank, mine is really hokey.