heating problem

Johnnydidd

Johnnydidd

Well-known member
I have always been a great fan of the flathead v8, my 53 Victoria is in excellent shape. everything new in the cooling system, but it still runs warmer than I think it should with ac, it will run on hot day around 210 degrees with ac. My question is would an overhead valve like a 1956 Mercury still have the same problems
 
Although flatheads were known for running hot it's not necessarily engine design that dictates operating temperature. Adding A/C adds heat to any engine due to the extra work the engine must do to run the compressor, plus the heat rejected from the condenser transfers to the radiator due to air flow and its proximity to the radiator. The hotter it is outside the more heat the system has to deal with. Are you running an electric fan or the stock 3 or 4 blade one? Or both? What is the opening temperature of your thermostats? If you're running 170 or 180 degree 'stats try 190 or 195. This may seem counter intuitive, but 'stats with lower opening temperatures will not regulate coolant temperature when it gets much over the 'stat's specification. The stats will be wide open all the time so the coolant doesn't spend enough time in the radiator before it returns to the engine. Also, when adding A/C be sure to seal all openings around the radiator and any holes in the core support. This will force more air through the condenser and radiator. And make the passenger compartment as air tight as you can and insulate the firewall, floors, doors and roof to reduce the heat load so the A/C doesn't have to work as hard.
 
My '50 Ford with a flathead V8 will run on the warm side in the worst of the Texas heat and pretty much mid band the rest of the time. No air conditioning on this car and everything Dobie says makes perfect sense. In normal weather (90° or less) and at normal speed limits, my engine temperature stays pretty much mid band. If running the engine at high speed for any significant distance, then the temperature does crowd the boiling point. I did run this car in the Big Bend Open Road Race this last April and pretty much found the engine temperature limits when running the car for 118 miles at basically wide open the whole distance. My car has 4.27 rear gears and overdrive.
 
Are you measuring the engine temp with an oem in-dash gauge or something else?
If an in-dash gauge is reading incorrectly you may not actually have a problem.
Double check to see if the temp indicated is actually correct, or at least really close.

You can probably borrow or buy a hand held infrared temp gun. (under $20)
 
at 90 deg ambient with air it runs 210 at 70mph in od using antifreeze it not suppose to boil until 245 deg. I use temp gauge on dash, plush one mechanical gauge, plus infrared temp gun. in the middle of head where the temp pickup for all three gauges reads the same, but checking the top of radiator it will measure 200 deg. I had an 17" electric fan with shroud which really worked great in the city, but on the highway it wouldnt cool very well, it would go way over 220. I finally put on a 6 bladed fan blade works great in city with the ac on and on the highway will stay around 210. I am using 160 deg thermostats. Dont you think an overhead valve would run much cooler?
 
Again, it depends on more than just engine/cooling system design. I'd try higher rated thermostats (180/190) before throwing away a perfectly good flatty. If you have an automotive A/C shop in the area you could have them look it over to see what improvements can be made. Old cars that weren't built with A/C in mind usually take some fiddling to get everything balanced out. 160 degree 'stats are way too cold even without A/C, IMO.
 
How old are the water pumps? Just curious since you didn't mention it. Not that I'm sure new ones would be your cure.

Try the higher temperature t-stats, easy and cheap enough. AC probably adds a good 20-30 degrees to the overall operating temperature.
 
You stated that everything in the cooling system is new. Does that include the radiator. Some aftermarket radiators have so many fins close together that at speed air cannot flow through the radiator fast enough. You say that around town it cools enough, but on the road it overheats. Sounds like an air flow problem to me. John
 
190 degree thermostats..july hot runs all day at 185/195...accelerate to 70 mph which means more fuel...more fuel generates more heat..raise your right foot back to 60 mph ,,the temp will settle back to 185/190 degrees..these flat engines were to operate perfect at 50/55 mph on 2 lane roads....I have been running my flattie for over 20 years..with a/c....use your head ,,if your running 70 mph into the afternoon sun in july hot or texas sun or climbing Jellico,,7 lb pressure cap ,,temps can skyrocket to boiling 212,,however with extra pressure cap..212 isn't boiling.. raise your right foot ,I'm done
 
I wasn't planning to change out the engine on my 53 Victoria, I was thinking of buying a 56 Merc, was wondering about heating with ac on 56 merc?
 
Ok, the 56 Merc, with a y block and adding a/c. Almost everything above applies to any engine, and Dobie covered it pretty well in his second post.

If you go over to y blocks forever and search "Greenbird56", you'll find a series of post on cooling. From restricting the w/p bypass, to Hayden fan clutches to fan blades. It's going to take some searching, and Greenbird is sometimes on here.

His solution works in Tucson at 115 degrees, but I don't think he has a/c. But 'birds are much harder to cool than the full size cars. With the right shroud, fan, sealing, etc. a/c in a Merc shouldn't be a problem.

My bird runs an aluminum radiator, full shroud, and electric fan. Small additional fan on the condenser. A/C setup from ClassicAutoAir. On a 90 degree Seattle day, in traffic, the main fan runs 90-120 seconds on, then off for 2-3 minutes. It doesn't get much hotter than that here, but given the run cycle, I'm probably good stopped to about 100 degrees. But I had to use all Greenbird and Dobies items to get there. Again, a full size car, with the motor clean (not rusted up in the water passages) should be doable.
 
Johnnydidd said:
Do you think louvers would help?
Click to expand...
No.

In regards to your question regarding the overheads and heating, the Ford/Mercury Y-Block engines introduced in 1954 did not have the heating problems that the Flatheads were noted for. Factory air was supplied on some of those early overheads with simply a multi-bladed fan and a shroud being needed to aid in the cooling.
Ted Eaton.
 
One of the problems with heat in the flathead is in their design. The exhaust ports pass through the block water passages, putting more heat into the water. John
 
Ted Eaton and John, this is reason I asked the question. It makes sense to be cooler on the way the engine is design.
 
Dobie Gillis said:
Again, it depends on more than just engine/cooling system design. I'd try higher rated thermostats (180/190) before throwing away a perfectly good flatty. If you have an automotive A/C shop in the area you could have them look it over to see what improvements can be made. Old cars that weren't built with A/C in mind usually take some fiddling to get everything balanced out. 160 degree 'stats are way too cold even without A/C, IMO.
Click to expand...
Agreed..start with the stats. Also, in my DeSoto, I had a radiator built (adding cores) which allows coolant to remain in the radiator longer. I may be Old School but i would take a Flatty over a OHV any day.
 
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