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1953 original 215 CID. Completely rebuilt. Probably got about 3000 miles on it. 160 degree thermostat. Never run above 170 even on hot days. Radiator clean when restored. Then it started running hot. I don't drive it very much. Always keep 50/50 coolant/water in it. Pulled radiator. Shop "boiled" it out. Took for a ride. Didn't help. Had to pull over and let it cool off before getting home. 212* I run a coolant flush and flushed radiator several times. Installed new 160 degree thermostat. Temp still ran up to 190* with ambient temp in the mid eighties. Got home and let it idle for several minutes. Temp climbed up to 200* Only simple thing I haven't done is replace radiator cap. Hoping/thinking it shouldn't be head gasket or head. Or it would still running up to 212* at highway speed.
If radiator has been rodded out (not just flushed), water pump good, belt not slipping, shroud in place, good T-stat maybe its a gauge or wiring problem.
What 49r said /\. Check temperatures with an infrared thermometer. Check temperatures at the thermostat housing, top of radiator, and various places along the radiator top to bottom. Post results.
Edit: Is the heat riser opening?
Themostat is installed correctly. Definitely over heating. No gauge malfunction. Using after market mechanical gauges. When I had to pull over to let it cool off. Radiator was gurgling and puking coolant out of over flow tube.
If there is cleaning solution residue in the system (detergents, acids, whatever) it can cause foaming, lack of heat transfer, etc. Try a good clean water flush and refill.
I don't have the same engine set up you have... but I had an overheating problem (common in Texas).
I tried a cooler thermostat, new radiator fluid etc. Our's came down to (2) basic issues:
1) Timing - If your timing is off or your carb. is running lean it can cause you to run hot. I'd make
sure you check both the timing & the carb.
2) Air Flow - We were running north of 210 degrees - I wasn't comfortable. So... I tried everything
& finally we gave up & went for maximum Air Flow. We picked up a big 18 inch Mark VIII style 2 speed
electric fan (V8 Thunderbird). Cruising at 180 degrees now.
Good luck up there in Waco.
Ben in Austin
1950 F1 (351W/AOD)
(160 degree thermostat isn't going to do the trick - thermostat just opens sooner but the engine will still go straight to it's normal operating temp. Id run what ever the stock thermostat is for the engine).
3000 miles of being OK, and now all of a sudden its over heating? You confirmed you definitely have a clean radiator and have plenty of air flow through it. That leaves coolant flow.
You have a new T-stat, water pump, belts and good coolant. Gauges are good. I would verify flow. Not sure about this engine but, I have seen water pumps have impellers fall off. I have seen bottom hoses suck shut at higher revs. Head gasket or casting crack can put compression in cooling system blowing coolant out too.
Good luck and please let us all know what you end up finding. I hope it doesn't get too expensive for you.
Just a thought have you checked the hoses? I've seen them swell up on the inside and cause restricted flow. Can you put a pressure tester on the radiator and see what pressure it gets to. We have all seen head gaskets let loose to water jackets and leave oil unscathed. If all seemed good, I'd maybe try back flushing through the heater hoses. You didn't get some of the funky Dexcool coolant in there did you???
was the block vatted? If not there could be some rust scale blocking some holes an causing it to run hot. I popped the back bottom freeze plugs on my 302 and flushed it out the best I could before installing my new radiator. If the old radiator has been rodded and cleaned it should be working good. I think I would do the same stated above and check flow. Lots of bubbling would or could be a sign of a head gasket problem. You can also turn the heater on and see if that wont help cool it down a little. I think I would order or purchase a new water pump gasket and pull it off and check it out. Whats that the pressure on the cap 5# ??
Fordf348. to answer your question that. Rodded out is when the radiator shop removes the tanks from the radiator, be them like on my 54 would be top and at least and hopefully bottom and then run a rod like a welding rod down through the cooling fin. this will remove scale and other build ups reducing flow as well as cooling ability. then they are done they resolder the tank and check for leaks.
Kurt nailed it. I have seen plenty of radiators that were flushed with acid or various cleaners that "look" brand new inside. After flushing mine the brass inside looked new.
The tubes typically plug up down lower. Unless the tanks are removed and a cleaning rod pushed through each tube, it will not be clean.
My 4 row brass core had a tag showing it was last serviced in 1996. It looked clean and my engine did not run hot here in Tucson. I had it rodded out because the cooling system was NASTY before I cleaned it out. The shop told me the radiator was in great shape but 50 or 60% of the tubes were plugged.