59 Block cooling question

Fredb_

Well-known member
My 100HP Flathead seems to cool fine when running down the road at 30+ mph. In fact I don't need to run the fan when driving at those speeds. I have flushed the system a couple of times since I put it together and did get some rusty junk out. I'm not sure how well the block was purged when it was rebuilt as this was done before I got the engine. I have installed 180 degree high-flow thermostats.
http://www.speedwaymotors.com/180-Degree-High-Flow-Thermostat,1836.html
I am also using a 14" electric fan on a switch. It pulls air through from back.
http://www.summitracing.com/parts/mar-mp146k-6
I have a new 4lb radiator cap.
When driving in stop and go traffic the engine heats up, especially if I have to sit still for very long.
Any suggestions that I can do to improve this or is this the way it is? Thanks!
 
The fan should run constantly when sitting ,Does yours cool it adequately .Most radiators get crud on the top of the tubes from the block if you do not run a stocking ,try reverse flushing from the bottom hose.
 
original water pumps?? how hot are you talking when it is "heating up".....cool back down when moving after idling??.....Mike
 
I have my fan on a switch that I turn on when engine reaches 170 or so. I have run this engine without thermostats and had similar results. I did wonder about the engine RPM and whether it was fast enough to adequately circulate water. I have no tach, so I would be guessing, but I had it mostly at a "low" idle. This was during a cruise the other night.
 
Two new water pumps, new belt with inch or so of tension. My original temp gauge went to the top. I have a second gauge on passenger side of block that appeared to be over 225.
 
Sounds like everything is good except the radiator. You haven't said anything about its condition. Might want to check it out - get it cleaned or even rodded. Might try filling cooling system with vinegar and run it for a few days then flush out. Here's one way to effectively and efficiently backflush the 59A: http://www.fordbarn.com/forum/showthread.php?t=83557
 
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Old rad's tend to loose the conductivity from tubes to fins because of years of corrosion and the only fix is a new core.
 
Yes, did have the rad checked out at a local radiator specialist who fixed a couple of leaks and flushed it. Part of my flushing process was the vinegar treatment which did get a lot of rust flowing from the engine. I did that a couple of times. Does the RPM need to be at a certain level to circulate the water efficiently?
 
Sounds like you have gone through the basics. The thermo fan you have I would say is too small, You would want a 16" one and with a shroud. If your radiator is the old style original I would think only a Spal can pull the air through it. Put it on a thermo adjustable switch too.
 
did he rod the cores, there is no product that will clean a radiator with plugged cores the cleaner has to run thru the core to let the cleaner work
 
Yes, I may need to consider re-coring the radiator. Before buying the 14" fan I measured across my radiator and it seemed a 14" diameter fan was about as big as would practically fit. A shroud would certainly be worth trying as well. I purchased a fan control that did not quite work as hoped. My system is still 6 volt positive ground which is probably the issue. If anyone has used this control or another with 6 volt pos ground, I appreciate any help.
 

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Yes, I may need to consider re-coring the radiator. Before buying the 14" fan I measured across my radiator and it seemed a 14" diameter fan was about as big as would practically fit. A shroud would certainly be worth trying as well. I purchased a fan control that did not quite work as hoped. My system is still 6 volt positive ground which is probably the issue. If anyone has used this control or another with 6 volt pos ground, I appreciate any help.

I can't help you with the controller, but it has lots of negative reviews on Amazon.

If your car cools at 30 MPH, it sounds like you have an air flow issue at low speeds/idle. Does it try to get warm when driving at high speeds, like about 70? If it does, your radiator might be marginal. I had these symptoms and solved it with a modern radiator.

Can you get a mechanical fan in there? Unfortunately when we deviate from original in these old cars we sometimes create more problems.

If I calculate right, your fan pulls 22 amps on 6 volts. That is quite a bit of current. Do you have it on a relay with heavy wire? There are dual 12" fans that will fit the tall, narrow radiator but I would be concerned about the 6V generator/alternator. In the end you will have to consider your symptoms and make your best decision based on your circumstances. It's trial-and-error sometimes, and we often have to do and redo. This is a good forum to get the benefit of others' experiences.

I wish you luck, keep us posted on your progress.
 
I've only had it up to about 55....:( ....on these Oregon back-roads 70mph would give me a case of white knuckles.
The original generator had the fan blade attached directly to the front. My current generator setup doesn't leave room for the fan that would run off the outer crank pulley. (I'm running a '46 100hp) That's why the electric.
Trial and error is right. When I figure it out I'll brag about it....I mean share what I learned on here. Thanks!
 
Usually what you do on a 1946 59AB engine is go with the generator/fan and single pulleys and single belt that was original to the car or truck.You use crankshaft pulley from a 1939 Ford Standard 85 hp,Ford part# 81-C-6312.This is what a Ford garage would have done when exchanging a 46-48 engine in an early Ford with single belt. My 37 has a 46 Mercury engine in it with 37 type generator fan mount,actually mine is a 37 generator housing with a alternator built inside it.
 
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Put a large house type fan AGAINST the grill and run the engine at about a speed of 15 MPH this will tell all. Remove the thermostats before the test and after it cools do it with the stats. Use a laser pointed thermostat and take the temperature on the neck of the head 1/2" below the radiator hoses. This is the only temperature you need to worry about. G.M.
 
GM, that sounds like a good way to determine if the fan is the issue. I will need to break down and buy one of them new-fangled laser thinga-ma-jiggies. Thanks for all the feedback!
 
GM, that sounds like a good way to determine if the fan is the issue. I will need to break down and buy one of them new-fangled laser thinga-ma-jiggies. Thanks for all the feedback!

They are down in the $25.00 range. G.M.
 
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