So I picked up a ford shoebox with flathead v8 recently and decided to take it on a 60 mile trip to test out the engine after driving around town with no issues. After about 30 minutes in traffic. Someone said your car is leaking badly...I pulled over and coming out of the pressure relif/ overflow hose on the radiator was tons of coolant coming out fast....I undid radiator cap with a towel and steam came flying out everywhere....radiator had no visible fluid in it after overheat....I have o temp gauge because I haven't hooked up the gauges since the rewire.....I added water to the radiator and let it cool down...... My buddy suggested checking to see if the thermostats got stuck or faild shut.....I took of and checked where I was told thermostats were and there were none. Like someone removed them....then he suggested hooking the temp gauges I have up to see if one head gets hotter faster which means one of the 2 water pumps may not be working. I just rewired and switched to 12v with alternator. Both water pumps spin and both belts seem tight so I'm not sure what could be causing the issue Before I replace both water pumps are there some other tests that I should do to find out what's not functioning properly? How do you check if water pump is not working? Any help would be greatly appreciated.....Thanks in advance....
I have never put a wrench to a flat head, but start with the basics. First, put in a thermostat (or 2). They also help keep water in the radiator to cool it longer. How is your timing? Two relatively simple things before you start putting a lot of money into parts that might not necessarily fix it.
ok. do you have a overflow catch of some sort? these radiators do not like to be filled to the top. let it determine it's own fluid level, trust me.
1X Running with out thermostats is trouble in flatties, water flows too fast thru the radiator so it wont cool.
Go over to the Early V8 forum at FordBarn, a sister forum to the Hamb, and run by Ryan. They speak nothing but flathead there. Flatheads require a different approach to most other engines, as an example, the old myth of slowing coolant flow down with thermostats or restrictors is just that, a myth. Likely causes of your problem are many..... timing out, partially clogged radiator etc, etc.
I'm not a flat head guru but I have dealt with this problem on my fiends 37 truck. Weld a washer into the thermostat housings with a 5/8 hole. This will slow down the water flow enough for the radiator to be able to cool it. Posted from the TJJ App for iPhone & iPad
First thing to fix is your temperature gauge. Get it working so you can monitor what's happening in the engine compartment. If you don't, there's a good channce your next thread will be "Where can I get a replacement for the cracked block in my shoebox?".
The problem may lie in the distributor. It's an all-vacuum setup that never really worked well, and got worse with age. The advance quits, and retarded spark means a hot running engine. That's why rodders put small-block Chevy distributors in them, or Mallory's. Also, are you sure you have a '49-'53 carb on the engine? The earlier ones look and fit the same, but the vacuum port is not right for the later advance setup and it won't work right. It will actually retard the spark as the rpm goes up, which is not good!
Most times when an engine that over heats going down the road ...it is a clogged radiator core. I had it happen to me on a modern car. It ran normal temps until up to speed and then it overheated. Replaced the radiator with an exact duplicate except it was not clogged and all was well. An infra red thermometer can probably locate the clog. Lots of wives tales about flatheads overheating. I was wary of this when I first got mine.(I'd heard all the BS too) I used a stock non-pressurized recored 32 radiator and a stock fan and I need thermostats to get it up to temp. Don't believe all the regurgitated hype about flatheads over heating.
Not in my case. I never ran thrmostats in mine and it never overheated. Ran under 160 all day long. Mixture of half coolant and half distilled water in the rad. If I filled the rad to the top....it would puke unil it found it's level and that was that!
Funny I had the same issues and I even tried the washer and small hole drilled into the T-stat, none of these worked. I replaced my waterpumps put in a brand new pumps. I put in a new radiator, went back to a normal 180 t-stat's and switched to electric fan all my issues went away. Oh and I installed two temp sensors to monitor both sides. The driver side seems to be slightly cooler then the passenger side whick I heard was normal. Cost me a bit of coin to do this but now no more issues=happiness. Good luck. Brent
As already mentioned, look at the many threads on Fordbarn, some of them mine. An option to offshore repro pumps is having your existing pumps rebuilt by Skip Haney in FL. http://www.fordcollector.com/ He installs high flow impellers. Overheating at idle can be a lot of things but mostly water and/or air flow. Overheating at highway speeds (what I struggled with) can be timing or just not enough radiator. I had a recored original radiator and still overheated until I broke down and got an aluminum radiator. Cruised to a show in September in 90 degree weather with no problems. Skip also rebuilds distributors. If you have an 8BA you can also get a Chev distibutor with a proper mechanical advance curve from Bubbas Hot Rod in IN: http://www.lindertech.com/bhrs/ Good price on aluminum radiators made in USA: http://www.bricethomasradiator.com/
You should let it cool down first and then add the water, especially with how "dry" your cooling system was. Sometimes when you add cold water to a hot engine you end up asking: Even though the temperatures aren't as extreme as when welding, if you cool cast iron too quickly, it can crack.
1. Confirm exact temp. 2. Check the coolant for combustion gasses … kit from auto part store. 3. Coolant checks good … confirm no ignition issues… <<<#1 problem 4. Look at cooling system - Rad - theramastats - clean block …………………
Start with the radiator. Forget all that crap about slowing down the flow with stats and washers, etc. That's a bunch of crap. There's no such thing as the water going too fast through the radiator. Pull your radiator and have it checked (flow tested by a radiator shop. If it checks out then you need to clean out the block.
Volumes are written here on Overheat flatty issues. Take one step at a time and start with the easiest. After reading Hamb threads on this issue you will have 10-15 items to check. Go through each of them and if you are still having problem get back to us. Beware, not all answers here on this thread are accurate. Read first and you will be able to sort out what really works. Good luck and be patient.
Ok so I believe it's fixed! Here's what I did...I drained radiator and installed 2 fail safe thermostats ( remember mine were missing). I then installed 2 separate temp gauges for each head. I filled radiator back up with 50/50 coolant bright green stuff. I tightened one of the thermostat housings and cracked it like a jackass. I freaked out went to pep boys and modified a chevy one!!!! Temporarily until I get a replacement but it works fine. It's for an early year Chevy v8... I ran car for a while and the temp never got above 180. On the passenger side head it got to about 200 and I freaked but them dropped down quick. I'm assuming first time the thermostat opened and coolant rushed into engine....after that stayed between 180 and 190 each side is pretty close to the exact same temp....In the morning I'm driving to a classic car meet up and will test engine a little more but I'm pretty sure not having thermostats was def the issue THANKS TO EVERYONE FOR THERE HELP
One more question. Since I did ad cold water to a majorly overheated car. How do I make sure block did not crack? It's not leaking or dripping anywhere but is there a way to tell besides that?
Best guess is just watch your oil and only panic if it turns into a chocolate milkshake. You can do a lot of tests, the simplest will involve hooking a air hose to each cylinder at tdc and looking/listening for bubbles in your open radiator and also listening for hissing at the oil fill tube. Hissing at the crankcase is not necessarily a cracked block, it could be leaking past rings. Mostly just wait and see if your oil level rises or turns milky. I wouldn't worry too much unless that happens.
Welcome to the world of flathead Fords. Your problem is more common than you think. Check your engine oil. If you cracked your block the oil will have water in it. But you should never add cold water to any engine that is hot enough to boil. After placing high volume water pumps, re-coring the radiator, using Barr's stop-leak, Wetter Water and an electric fan to use at traffic lights, I finally got my `35 Cabriolet to run cool.
I'm kind of voting with the guys that want you to check your radiator. If you can drive slowly around town with out the temperature climbing abruptly but getting out into higher speed stop and go traffic and your engine starts to heat up quickly that is a good sign of poor cooling thru the radiator. As you go out to drive at todays highway speeds 55-70 your flathead engine pumps a lot of water to the radiator, if any of the tubes have an obstructed flow from rust or junk in them it prevents the water from flowing thru the radiator. If you have an old radiator the outer tubes can become pluged with rust residue and oil film goo form a leaky water pump. Water still flows from the center tubes giving the appearance that everything is ok but the radiator isnt doing its job. This creates two issues first the water builds up in the upper tank and has no place to go, its only escape is out the over flow so you loose water. Second as you loose water you loose the ability to cool the engine so now the low water level never gets to cool suffficiently and things reach the boilng point. It nice to see that you got everything back to gether with out any mishaps but before you go for a long trip give your car a test drive at higher speeds and monitor the temp. If it starts to climb to fast your next step is to check the radiator, that means taking it to a good radiator shop where they can remove the tanks and clean out the core tubes.
water in oil can also mean a blown head gasket as well.once you have sorted the temp situation do a combustion test for gases in the coolant..napa sells the kit
I am confused. Slowing the flow down lets the radiator cool the water more. Slowing the flow down lets the water get hotter in the engine. You want the water to flow as fast as it can flow. Thermostats are used to warm the water for the heaters and defrosters. Like everybody said, slowing the water to cool the engine is a myth. Skips water pumps increase the flow and cool the engine better. Copper radiators have an "R" value about half of aluminum. Copper cools better. I have not been a mechanic but I graduated from the eight grade at Saint Patrick's grade school. The nuns taught us how to think.
You'll get water in your oil if the block is cracked, or coming out the exhaust (?) at least it will on overhead engines, I know nothing on flatties. Bottom line is your coolant level will go down
Common sense says if it overheats at high speed but is ok around town, it's a plugged or restricted radiator. Clean/rebuild/replace the radiator, use 2 thermostats, fix your temp gauge, common sense stuff. Oh, and don't let me drive it. I put holes in sides of flathead blocks the size of rods. They don't like me
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