Seems my 59 stamped 1948 flat head running Ilsky cam pre war Edmund’s heads older elder Brock intake tri power 3 super 97 with progressive linkage motors bored and built. Seems in-fore red gun shows radiator top 172 lower 180s at block at front between intake & head 193. At rear on top block between intake & head 213 both shot on flat of block. Temp gage has electric sending unit on head drivers side. Gage runs 190 /230 up and down and noticed it gos even higher lately. No boil overs + heads are real close front to back in temps rears run a higher makes since the block runs a warmer temp also. Brake in oil is still clean radiators a Brassworks with electric fan and custom shroud. These temps are driving me nuts!! Afraid to venture a long haul. Not knowing what going on. Any body out there going through this.
You’re measuring at completely different points in the cooling system of course they will read different. Water coming out of the radiator is going to be cooler than the water coming in. if it’s not puking or or running like shit I’d say it’s fine
What is the temp running around town, and what temp do you see on the highway at 55 or so? Based on what you posted, your temps may be in the ball park.
Check temp at the heads near the outlets by the thermostat. Temp should be fairly close to thermostat temp. If the temp goes up on the highway you may not have enough radiator. If the temp is going up at idle you may not have enough airflow through the rad. Your temp gauge reading over 230 would be worrisome to me, maybe check accuracy of the gauge.
190 seems fine. If it’s fluctuating a lot You might need to burp an air bubble out of the system. Get the radiator fill neck higher than the rest of the system by a fair amount and let it idle with the cap off and the bubble should want to travel up and out
That sounds okay. If it doesn't have an air bubble like Tim mentioned, you may want to try a different gauge.
Mark, Is your system pressurized? As I recall, flathead coolant flow at the rear of the block was always "hotter" due to inefficient water circulation. Ford tried to fix this in the 8BA by changing design and shape of coolant flow holes in both the block and the head gaskets. Take you car for a highway ride and record the temp at various speeds and also when driving around the city with stop and go driving. If it doesn't boil , you are good to go. I found that when I lived up north in NY and WI the engine ran a lot cooler (unpressurized stock system) than when I moved to FL where the ambient temperature is higher. I have since pressurized the system with a Griffen radiator and a 10 psi. cap. Engine is 8BA with early style heads.
Yes I had a brassworks radiator made with electric fan & shroud. I’m just think there’s no good gages. Accurate ! Just when I see it go fast to boiling point out of nowhere. But nothing happens.
Not a flathead expert, but have done engine cooling tests on military vehicles. I see you’re in Florida, so still could be warm/hot. Freezing right now at my place. Lol! As you likely know, coolant temperature will be largely affected by ambient air temp going through the radiator. Will also depend of course on heat rejected by the engine which is proportional to load on the engine. Don’t know the conditions under which you took the measurements, but assume the following: THIS IS AN EXERCISE ONLY TO SEE IF THE ASSUMPTIONS ALIGN WITH THE DATA. 1. Gross engine power to drive at 50 mph = 50 hp (likely less), but use this for simplicity. 2. 1/3 of the 50 Hp is rejected as heat by the engine into the coolant (for gasoline powered engines, typical assumption is 1/3 of gross power is useful, 1/3 is rejected as heat into the coolant, and 1/3 is rejected as heat through the exhaust). 3. So you have (50/3) = 16.7 Hp of heat rejected into the coolant. This equals 42,400 Btu/hr. 4. Assume you have 700 CFM of air passing through the radiator. 5. Using the formula for latent heating/cooling: Btu/hr = CFM x 1.08 x delta in air temp (F) or delta in air temp (F) = (Btu/hr)/(1.08 x CFM) delta in air temp (F) = 42,400/(1.08 x 700) delta in air temp (F) = 42,400/ 756 delta in air temp (F) = 56 This means you would need a 56F difference in the temp of the air entering the radiator and that of the temp of the air leaving the radiator. If the ambient temp increases by 10F, then the corresponding temp of the air leaving the radiator will increase by 10F. This is just an exercise to give you an idea of the variables, and how they affect the heat transfer from the radiator. If you know the CFM of the air going through the radiator, and the temp of the air entering (ambient temp) and that of the air leaving (avg), you can calculate the energy being rejected by the radiator. Of course, that energy will also be dependant on the mass flow of coolant into the radiator and the temperature of the coolant entering the radiator and also leaving the radiator. This amount of energy rejected to the air has to be equal to the energy rejected by the coolant. This amount of energy rejected by the coolant can also be calculated by the following formula: heat rejected (Btu/hr) = Specific Heat of coolant (0.83 Btu/hr/lb x F) x Mass flow rate of coolant (lb/hr) x temp delta (F) of coolant entering and leaving the radiator Not sure if you said there was only a 8F (180F - 172F) delta in coolant temp between the upper and lower rad hoses. Lower rad hose should be cooler than upper, but seems you have opposite from what I can read, but if one assumes this to be correct, and using the 42,400 Btu/hr heat rejected into the air figure, we can calculate the coolant flow rate. Coolant flow rate (lb/hr) = 42,400/(0.83 x 8) Coolant flow rate (lb/hr) = 6,386 (total) Assume density of 50/50 coolant/water mixture = 66.2 lb/ft3 Then coolant flow rate = 96.5 ft3/hr One gal = 0.134 ft3 This then equates to 720 gal/hr (total). https://fordbarn.com/forum/showthread.php?t=269442&showall=1 From this article above on the Barn, stk water pumps deliver about 65 gal in 5 min, or 780 gal/hr. So, assume two pumps deliver 1,560 gal/hr. Assume this flow rate corresponds to the engine speed at 50 mph. What this shows, based on ALL THE ASSUMPTIONS, is that the stk water pumps should deliver more than adequate flow to cool the engine. This assumes that the radiator is sufficiently designed to accommodate that amount of heat transfer. Again, it is really important to understand that ambient air temp has a direct correlation to engine coolant temps. The hotter the ambient temp, the hotter the coolant temp, so without knowing the ambient temp, engine load, etc, it’s almost impossible to determine if the coolant temps being measured are “problematic”. Feel free to review and critique my calcs as it has been almost 35 yrs since graduating eng school, and I’ve had to take time to do some reviewing/researching to come up with all this. I’m sure I’ve made some errors, but the point is to show that it isn’t that hard to do some “simple” calcs/scenarios to help determine if things make sense.
thank you this I can work with. I’ve worked with calcs most of my life designing electrical systems. I’ll put it to work.
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