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I was wondering what the normal operating temperature is on a flathead 8ba, i have a 1950 f1 and after about 15min of running the temp gets up to 200 degrees farenheit and steam starts to come out of the overflow on the radiator? i take it this isnt normal and i was wondering if anyone could give me any insight as to what my issue could be? thanks in advance.
I take it this is running in the garage, not driving? I can't tell if you have a fan shroud, which would help, but I'd suspect your thermostat(s) are bad. Beyond that, there are a dozen or more things it could be, but we'd have to know more about the engine and what you've checked/repaired on it.
sorry I should have given more detail, yes it is running in the garage, it is not driving, it does not have a fan shroud, i have replaced both thermostats,i have ran water through the rad till it came out clear and i am in the process of running the engine then draining the rad, refilling rad running the engine and draining it untill it comes out clear.
Looking down thru the filler cap opening, are the tubes caked with deposits? Rinsing with water really doesn't clean a radiator that well, it isn't likely to scour the tube surfaces clean.
With all your front end sheet metal off, and no shroud, the fan isn't likely to draw air thru the radiator, but just idling I'm surprised it gets that hot. Have you set the timing?
When flushing your rad , try doing it with the water going into the rad from the bottom and use a compressor also and shoot air in with the water .
You will be surprised how much more crud you will shift with the compressed air and water .
the tubes dont seem too bad to me, once i get my hands on a timing light i will check the timing, i also found that the truck idled fine with the vacume hose off that goes to the wipers but as soon as i hooked the hose up the engine would die.
Normally that truck came with a 160℉ thermostat. But you will have to pull the the thermostats to determine which ones you have. Also has the radiator been changed? How many lb. cap does it have? How are you measuring the temperature?
By taking the hose off, you are letting a bunch more air into the engine. Either your carb idle speed is set way low, or possibly your carb's power valve is blown and it is dumping too much fuel until you let more air in.
i think i may have installed 180 degree thermostats when i changed them, ill have to double check, it is the original radiator, how would i find out how many lb cap it has? and i am measuring the temperature with a non contact infared thermometer just reading the temperature off the heads.
i looked at the idle adjustment screw and it is tightened all the way in, so you may be right with the power valve blown, could a siezed wiper motor also cause that?
i think i may have installed 180 degree thermostats when i changed them, ill have to double check, it is the original radiator, how would i find out how many lb cap it has? and i am measuring the temperature with a non contact infared thermometer just reading the temperature off the heads.
If it isn’t written on the cap then you need to take it to NAPA-type parts store and have it tested. It should be 4 lb vs 14+ lb in today’s trucks. Also the cap is a different heighth that today’s caps.
i looked at the idle adjustment screw and it is tightened all the way in, so you may be right with the power valve blown, could a siezed wiper motor also cause that?
There are three idle adjustment screws on the carb.
Two are idle mixture screws, on the back side of the carb. They should be about 1-1/4 - 1-1/2 turns out from LIGHTLY bottomed.
The other one is the idle speed adjustment screw, that bears against the lever connected to the choke. It should be adjusted as a starting point such that the throttle plates are cracked open just enough to not be seated all the way.
ok i didnt know about the other two adjustment screws, ill have to adjust them and then re-adjust the idle speed adjustment screw that is tightened all the way in right now. thank you for the help
