They are boiling regardless of straight water or 10% anti-freeze and under reasonably moderate ambient temps. I am sure you're right in that the radiators aren't shedding heat fast enough but not so sure about the waterless fluid not helping. The evans fluid will not accept heat as well as straight water (heat capacity comparable to glycol) but then basically no fluid will. The problem is that with water as soon as 212 deg is reached then the fluid near the cylinder walls and combustion chamber flash boils at a microscopic level and thus stops accepting heat altogether. The evans fluid does not do this so the engine will run happily right up to about 270 deg at which point oil pressure can become unreliable. The viscosity is only a problem at low temperature from what I've read, not really an issue for me.

Why do you say the system has to be run under pressure to take advantage of the higher boiling point?

I have run several single and two part treatments through the radiators to de-scale, possibly the loss of efficiency is simply hardened rust deposits. As these cores are all soldered together care must be taken with how agressive the treatment used can be. 1920s cars with modern straight tube cores just don't look right, I know it's probably stubborn and unreasonable but that isn't an option for me.

Allan, I suspect the solution back in the old days was a new radiator, cheap and easy back then. I did talk to a very old mechanic about it, he told me to set up a big container of hot soapy water, an old bath with a fire under it works well apparently. Then use an electric pump and circulate the water through the radiator for 24-48 hours filtering the return water with a set of pantyhose. Probably worth a try!

 

Have felt temperature top and bottom by hand only, seems quite even and yes, they do drain quite quickly, for honeycombs. Both on V belts and fairly tight considering the age of the water pumps, haven't seen any signs of, or heard any slip.

 

Sounds to me like the radiator is not doing the job. Seems to me like it should be much cooler at the bottom if the honeycomb flows from top to bottom. Might be hand held thermometer time. Will the fan belt slip when the fan is turned by hand?

 

The solutions you can buy at the auto parts stores are nowhere near as powerful as radiator shops use. I'd try having them do it first.

I guess you're right, you don't have to run them under pressure, I'm having a hard time understanding a non-water mix. I don't think I'd want to run a cooling system at 270, I doubt your pump seals etc are good for that.

Is the core what you see at the front of the car? or is there a grille of some sort over it?

 

The 29 Pontiac was the first car to use a cross flow radiator, quite an innovation for its day. You can get the fan to slip but you have to pull pretty hard and then it's a 50:50 chance whether it will spin free or turn the engine.

 

The solutions used are well above the auto parts store level, the last one came from a high end chemical company, cost a fortune and did get a lot of crud out. The local radiator guy won't touch honeycomb cores, very few radiator places will.

The boiling point of 375 degrees is at one atmosphere. It does take a bit of getting the head around. I have no intention of running at 270, just saying that it becomes the new theroretical "danger point" as opposed to 212 deg. In any case the water pumps have all been rebuilt with modern seal material.

The core is the exposed part at the front, no covering or grille over it.

 

So I ask the question a different way. Does the temperatures at the outlet side of the radiator read considerably cooler than at the inlet side? To quote you earlier that the temperatures seem the same or even sounds like the radiator is not doing the job of cooling the coolant. Does not sound like the fan belt is an issue, especially at the low rpm you're talking about. I do believe I would obtain a hand held infrared thermometer and play it around the various sections of the radiator to determine if it is actually cooling the water.

 

I couldn't feel a big difference by hand but you're right, definitely worth investigating with an IR thermometer.

 

50% propylene glycol water solution has a boiling temp of 222*F. 60% solution has a boiling point of 225*F. I definitely wouldn't want to run a 1920 era engine at a higher temp than 220*. The damage higher temps will do to the engines will be far more costly than the cost of new radiators. Would an electric fan temporary addition allow you to drive the cars without overheating until the budget can handle new rads?
PS: never heard of Evans WC.

 

Good point, how about just a new fan blade with greater # of blades, or more pitch?

 

The litte red one has a thermo fan at the moment, made little to no difference. With only 57hp to start with I need or be careful just how big a fan I mount.

 

Do your Pontiacs have a water distribution tube? The later straight 8's had a tube running from the front of the engine to the rear. The tube had holes to make sure the rear cylinders received a flow of water. Many time the tube would rot in to and the engines would run hot and it was due to the rear cyl not receiving any water flow. Many times these engine were rebuilt and the modern builder had no idea about the tube and so the heating continued after a rebuild and engine block cleaning. Just a thought.
Good luck driving your cars.
Larry

 

You run the Evan's WC at zero pressure. And it works quite well.




Aussiecowboy I know some guys that run Evan's WC and they swear by the stuff. I plan to switch my vehicles over to it in the near future. If you do decide to run it, make sure to get all the coolant/water out of your vehicles before you add fill it.

 

I don't have any suggestions on the cooling issue, but I want to say this is a very educational discussion. Thanks guys.

Also, how about a better picture of the Jeep?

 

Electric fan size doesn't depend/affect engine HP.