1955-water pump smaller diameter pulley (1 Viewer)

zeroroadkill

zeroroadkill

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1955
Advice wanted: Some articles I've read mention that below 850rpm's there is little water flow even with the high output water pump, modified spacer and big mouth thermostat. Some suggest replacing the stock water pump pulley with a smaller diameter pulley. Has anyone changed out the stock water pump pulley with a smaller one and if so what diameter would you recommend? Did it help? Did you have to use a smaller fan belt?

Thanks in advance.
 
J

John Vierthaler

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Feb 21, 2023
Thunderbird Year
1955
Advice wanted: Some articles I've read mention that below 850rpm's there is little water flow even with the high output water pump, modified spacer and big mouth thermostat. Some suggest replacing the stock water pump pulley with a smaller diameter pulley. Has anyone changed out the stock water pump pulley with a smaller one and if so what diameter would you recommend? Did it help? Did you have to use a smaller fan belt?

Thanks in advance.
I don't know the answer to this but I would question if the faster flow of coolant would shorten the time going through the radiator thereby lessening the cooling effect.
John Vierthaler
Black '55
 
Ward 57

Ward 57

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Viewing forum 1955 - 1966 Classic Ford Thunderbird
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1957
I don't know the answer to this but I would question if the faster flow of coolant would shorten the time going through the radiator thereby lessening the cooling effect.
John Vierthaler
Black '55
Why do people think that faster flow will not let the coolant cool enough? I think that would only happen if the radiator is too small. Not likely with a stock radiator.
 
zeroroadkill

zeroroadkill

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1955
I’ve replaced the stock radiator with a custom 4 row radiator, high output water pump, big mouth thermostat, six blade fan, modified spacer and she still gets very hot in slow traffic on a hot day. Not sure what to do next. I thought of an electric fan but want to keep her as stock as possible. Only 56k original miles. Two Engine flushes showed no rust or sediment. Antifreeze clean and green. Wondering if pump speed would help?
 
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Ward 57

Ward 57

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1957
I’ve replaced the stock radiator with a custom 4 row radiator, high output water pump, big mouth thermostat, six blade fan, modified spacer and she still gets very hot in slow traffic on a hot day. Not sure what to do next. I thought of an electric fan but want to keep her as stock as possible. Only 56k original miles. Two Engine flushes showed no rust or sediment. Antifreeze clean and green. Wondering if pump speed would help?
How hot is very hot. These engines are known to run hot and don't mind a bit. Over the white line in slow traffic is not unusual and not harmful. 20-40 or even 20-50 will keep everything fine.
 
zeroroadkill

zeroroadkill

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1955
Maybe I’m chasing a ghost? At slow traffic or a long light on a hot day she will get to the end of the white bar, never reaches the final mark. Maybe I’m used to engines running at 190° or 210° . I need to laser check the the radiator temperature when she indicates over normal. Running she runs about 60%-75% on the gauge. On. 100° day in traffic she reaches the top of the white line. Am I being too paranoid?
 
Critterpainer

Critterpainer

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1955
Add a temporary mechanical temp gauge on the rt head just to do a reality check. Also see what happens when you turn the heater on when you think the engine is too hot.
 
Ward 57

Ward 57

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1957
Maybe I’m chasing a ghost? At slow traffic or a long light on a hot day she will get to the end of the white bar, never reaches the final mark. Maybe I’m used to engines running at 190° or 210° . I need to laser check the the radiator temperature when she indicates over normal. Running she runs about 60%-75% on the gauge. On. 100° day in traffic she reaches the top of the white line. Am I being too paranoid?
Sounds perfectly normal to me. My '57 reacts the same way with no issues.
 
CSPIDY

CSPIDY

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1957
I found with the modified spacer, I have flow at 600 RPM idle

If the engine is not overheating, ie blowing steam and pegging the temperature needle past the high end

There is no problem

I agree with Ward, 190 degrees would be ideal, on my water temp indicator that is at the very high end of the arc line
 
Gforni

Gforni

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1955
With our '55, it was running hot/overheating, and I swapped out the stock fan for the 6 blade, installed the high flow water pump and 190 deg thermostat. I also had the radiator boiled and cleaned, as well as installing an overflow tank (while not stock, it is very functional.) Using the stock temp gauge is somewhat misleading, so I use the laser temp and checking the top and bottom of the radiator, the thermostat housing and other areas, the car does not get much over the 145 to 190 degree temps, with the gauge in the 'center' bar area. We live in the South, so we get some warm days, and the car seems to do fine now since we swapped those parts out. The laser temp reader is worth the piece of mind.
 
J

jack-in-sac

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1957
I have observed over the last 25 years that many overheating complaints are either overstated or caused by other engine issues.
First How do you know you are overheating? Are you dumping coolant all over the ground? Just becasue you standard gauge says hot is often not a true indicator.I suggest a second sender installed in the other cylinder head and a quality aftermarket gauge.
Second Endemically the castin in the fifties was not as precise as later say in the 60s. Questions are: has your engine been rebuilt and if so bored out how much? Are all your other engine systems and components working properly? Are you using a Mallory distributor? There are mot questions but in answer to the above; If rebuilt,how much are the cylinders overbored? this iis not a common problem but does occur when the cylinder walls are thin. A faulty vacuum advnce can run the engine hot, timing an engine with a few miles on it to the timing mrks can be incorrect. This can result in poor performance and other associated problems. I suggest timing by vacuum. Have you recently or ever adjusted the valves? an out of adjustment rocker arm can result in a burned valve and a poorly and perhaps hot running engine.is your engine's carburetor jetted properly. A common change to a too large "modern" carburetor. For instance an Edelbrock 600c.f.m or greater is overkill. That carburetor out of the box is for a Chevrolet 350c.i. engine A 500 c.f.m carburetor is much closer to your actual needs.
The sum of my comments is: make sure all your other engine systems are correct before spending a lot of money on fixes tht may help but not solve your problems. I have a C code '57. It runs consistently 190 to 195 at extended distances at 70 to 75 m.p.h. with the air conditioning on. In town in traffic no real problems. Only occassionally in mid summer climbing a very long grade like Altamont have I ever had to turn the air-conditioning off. I took advice from Walt Nuckels and Jimmy Skoggins years ago to have a cool runnig engine and have been happy ever since. I also run a standard radiator and distilled water.
 
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