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Discussion Starter · #1 ·
Whilst diagnosing my car, I came to realize that the engine is running hot.. .too hot in fact. I don't remember it being so hot before the rebuild. Then I remembered that some antifreeze leaked out of the top of the engine because we forgot to screw the bolt and then we added more water (3 liters give or take). And it wasn't distilled water as well. Old man in the shop said it wouldn't hurt the engine that much.

Which led me to believe that the engine has cooling issues. Maybe that's why the engine stalls at high temps. But that's probably due to mechanical fuel pump leak.

All of this led me to the rabbit hole of coolant vs water vs water wetter. What I learned is that:

1. Coolant can't be used in racing (don't know why though), so they use plain water. 100% water also cools the engine better.
2. For regular folks, antifreeze is required so that water in your cooling system & engine isn't frozen on low temperatures. Antifreeze also has higher boiling point than water.
3. Water wetter increases boiling temp just like coolant and reduces the temperature up to 30 degrees.

About where I live - it's freezing for 2-3 months a year. So I do require a coolant. Water is a no-brainer and water wetter might give that additional support.

So this is what I concluded from my research:

I take coolant and water, mix it together real good, pour it in, but leave some space for water wetter. Then, add one bottle of water wetter and that's that. 49% coolant, 49% water and 2% water wetter. And of course, this time, I'll use distilled water and while I'm on this topic, I'd also like to ask for any tips on draining current coolant and water from the engine block?

I've an aluminum radiator btw.

Thanks!
 

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1970 Ford Mustang, Windsor 302 V8, C4 Automatic Transmission, Holley 600 Carburetor
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For draining the current coolant, what I have seen someone do is run a water hose through the system like in this video.
But what I usually do is let the car run while running a hose through the top of the radiator & leaving the petcock at the bottom fully open.
 

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First diagnose your issue. You say it's too hot? What temp is too hot? What signs are you seeing indicating and over heated engine? What's your engine, timing, carb set up etc... what's your cooling set up.

Ethylene glycol can't be used in racing because when it ends up on the track it's slippery and it's very very hard to clean up.

Antifreeze us also used so that your cooling system doesn't rust/corrode

Wetter watter claims those things....
 
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Discussion Starter · #4 ·
First diagnose your issue. You say it's too hot? What temp is too hot? What signs are you seeing indicating and over heated engine? What's your engine, timing, carb set up etc... what's your cooling set up.
Timing and carburetor set-up is the same. We only drained the radiator and transmission.

The air filter itself is hot. I ran it for 30 minutes yesterday and it stalled on its own. Fuel pump is leaking so that's why I think it's stalling, but I'm 100% sure the car wasn't this hot even when I ran it like a race car around the town for 1-2 hours.
 

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Adding onto Redneck's thoughts, it's best to check the actual temperature of your engine before coming to a conclusion. You say it stalls at high temperatures, but maybe it's because of a fuel boil? The fuel could be getting hot enough to where it's causing vaporlock. Since you say it only happens when the engine gets hot, it could be one of your problems.
 

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Timing and carburetor set-up is the same. We only drained the radiator and transmission.

The air filter itself is hot. I ran it for 30 minutes yesterday and it stalled on its own. Fuel pump is leaking so that's why I think it's stalling, but I'm 100% sure the car wasn't this hot even when I ran it like a race car around the town for 1-2 hours.
When you said you ran it for 30 minutes yesterday, was it idling or were you driving it around? The reason it probably didn't get too hot when you raced it around town is probably because of the air flow that the radiator is getting at moving speeds.
 

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Timing and carburetor set-up is the same. We only drained the radiator and transmission.

The air filter itself is hot. I ran it for 30 minutes yesterday and it stalled on its own. Fuel pump is leaking so that's why I think it's stalling, but I'm 100% sure the car wasn't this hot even when I ran it like a race car around the town for 1-2 hours.
Yes the engine/parts of the engine get hot, too hot to touch, Especially idling with no air flow around it
 

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I would also recommend checking the actual temperature of engine parts without relying on the stock temperature gauge. That's a lesson I learned as I thought my car was originally getting too hot, but I learned that it can be inaccurate.
 

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Antifreeze is also anti corrosive and this is why you run it in your vehicle to prevent rust. Prestone makes a rust inhibitor that is not antifreeze so you can run straight water in your engine but it sounds like antifreeze would be the best for you given your climate.


I do use Water Wetter in our dirtbikes and my diesel truck. Would throw it in the Mustang too but it's not run long enough to need it yet.
 
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Whilst diagnosing my car, I came to realize that the engine is running hot.. .too hot in fact. I don't remember it being so hot before the rebuild. Then I remembered that some antifreeze leaked out of the top of the engine because we forgot to screw the bolt and then we added more water (3 liters give or take). And it wasn't distilled water as well. Old man in the shop said it wouldn't hurt the engine that much.

Which led me to believe that the engine has cooling issues. Maybe that's why the engine stalls at high temps. But that's probably due to mechanical fuel pump leak.

All of this led me to the rabbit hole of coolant vs water vs water wetter. What I learned is that:

1. Coolant can't be used in racing (don't know why though), so they use plain water. 100% water also cools the engine better.
2. For regular folks, antifreeze is required so that water in your cooling system & engine isn't frozen on low temperatures. Antifreeze also has higher boiling point than water.
3. Water wetter increases boiling temp just like coolant and reduces the temperature up to 30 degrees.

About where I live - it's freezing for 2-3 months a year. So I do require a coolant. Water is a no-brainer and water wetter might give that additional support.

So this is what I concluded from my research:

I take coolant and water, mix it together real good, pour it in, but leave some space for water wetter. Then, add one bottle of water wetter and that's that. 49% coolant, 49% water and 2% water wetter. And of course, this time, I'll use distilled water and while I'm on this topic, I'd also like to ask for any tips on draining current coolant and water from the engine block?

I've an aluminum radiator btw.

Thanks!
Mustanger,
U are correct in your attempt in eliminating mineralized water from the engine block and the heater core, while u r servicing the cooling system.
Some blocks have screw-in pipe threaded plugs on the side of the block for draining.
I STRONGLY SUGGEST U LEAVE THESE ALONE, unless the engine is outa the car. If so, replace the iron plug with pet-**** type drains, like what's at the bottom of the radiator.
To purge the block and heater core, u'll need several gallons of distilled water. BTW, U can get all u need, if you have access to a typical household dehumidifier. Or u can buy it by the gallon at Walmart. 6 gallons should be plenty.
The best way I've found to flush the block and heater core is to do the following.
Disconnect both radiator hoses, top & bottom. Remove the thermostat housing, leaving the hose attached. Remove the thermostat for the flush, because u'll be dumping cool water in and the thermostat won't open, u want everything open. Replace the thermostat housing & upper hose, don't worry if it leaks during the flushing process.
Let as much old coolant run out as possible.
Then start dumping gallons of distilled water into the block, via the upper hose. You can start the engine during this process too. This will get the clean distilled water flowing throughout the block and heater core, with the water pump's help.
Once the old coolant is out, u r done.
U can tell when all the old coolant is out when the water runs out clear.
Shut the engine down and reconnect everything. Fill the coolant system with a 50/50 mix of distilled water and antifreeze, leaving room 4 your Water Wetter. All u need to do is cover the radiator core & it's full. If u have a coolant overflow recovery system, u cal fill the radiator to the top. 🙂
 

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My engine compartment with a 351c gets "too hot to touch" in summertime and she don't run too hot.
Get you a infrared temp gun!
It can be normal for an engine to get hot after long drives or time idling. You may be worried over something little. Do a coolant flush and measure the temperature of the engine with a temperature gun.
 

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It can be normal for an engine to get hot after long drives or time idling. You may be worried over something little. Do a coolant flush and measure of the engine with a temperature gun.
Yup, I shoot engine temp on the T stat housing. 210 °F is not too hot.
 

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Discussion Starter · #14 ·
When you said you ran it for 30 minutes yesterday, was it idling or were you driving it around? The reason it probably didn't get too hot when you raced it around town is probably because of the air flow that the radiator is getting at moving speeds.
Yesterday it was idling for 30 minutes. Then it started to cough and the engine turned off. Couldn't start it.

And when I drove it, few times when I slowed down at red light, it did have issues, had to go into neutral and give some gas to keep it alive.
 

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Discussion Starter · #15 ·
Adding onto Redneck's thoughts, it's best to check the actual temperature of your engine before coming to a conclusion. You say it stalls at high temperatures, but maybe it's because of a fuel boil? The fuel could be getting hot enough to where it's causing vaporlock. Since you say it only happens when the engine gets hot, it could be one of your problems.
It might be vapor lock. Still don't completely understand why it's happening and how I can prevent it, but that's one of the possibilities for sure.

Do you mean the fuel within bowls?
 

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Yesterday it was idling for 30 minutes. Then it started to cough and the engine turned off. Couldn't start it.

And when I drove it, few times when I slowed down at red light, it did have issues, had to go into neutral and give some gas to keep it alive.
Idling it for 30 minutes will definitely heat your engine up with no airflow as stated before by me and previous commenters. That's why your engine probably dies after 30 minutes due to no outside force to help it cool down. That and possibly fuel boil as stated before. What are you using for your fuel lines? Depending on what your using, it could be causing the lines to get too hot causing vaporlock possibly.

On the issue of red lights, I have a similar problem with red lights when pulling out of the neighborhood for college. It's because the car still needs time to warm up for me. But after getting it past the 2nd light or so, it seems to be fine.
 

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Discussion Starter · #18 ·
Mustanger,
U are correct in your attempt in eliminating mineralized water from the engine block and the heater core, while u r servicing the cooling system.
Some blocks have screw-in pipe threaded plugs on the side of the block for draining.
I STRONGLY SUGGEST U LEAVE THESE ALONE, unless the engine is outa the car. If so, replace the iron plug with pet-**** type drains, like what's at the bottom of the radiator.
To purge the block and heater core, u'll need several gallons of distilled water. BTW, U can get all u need, if you have access to a typical household dehumidifier. Or u can buy it by the gallon at Walmart. 6 gallons should be plenty.
The best way I've found to flush the block and heater core is to do the following.
Disconnect both radiator hoses, top & bottom. Remove the thermostat housing, leaving the hose attached. Remove the thermostat for the flush, because u'll be dumping cool water in and the thermostat won't open, u want everything open. Replace the thermostat housing & upper hose, don't worry if it leaks during the flushing process.
Let as much old coolant run out as possible.
Then start dumping gallons of distilled water into the block, via the upper hose. You can start the engine during this process too. This will get the clean distilled water flowing throughout the block and heater core, with the water pump's help.
Once the old coolant is out, u r done.
U can tell when all the old coolant is out when the water runs out clear.
Shut the engine down and reconnect everything. Fill the coolant system with a 50/50 mix of distilled water and antifreeze, leaving room 4 your Water Wetter. All u need to do is cover the radiator core & it's full. If u have a coolant overflow recovery system, u cal fill the radiator to the top. 🙂

Appreciate your response1

Coolant came out from the small hole right behind the cables (see picture for reference). That is, when we forgot to plug it in fully and started the engine. I assume I can attack a long tube to that, start the engine, open up the radiator and just pour distilled water into the radiator and all of the coolant/tap water will come out of that tube and like you said, after I see only water coming out, it means it's all clear and I can pour the new coolant/distilled water mix with water wetter.

Car Motor vehicle Automotive design Hood Vehicle
 

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Discussion Starter · #19 ·
Idling it for 30 minutes will definitely heat your engine up with no airflow as stated before by me and previous commenters. That's why your engine probably dies after 30 minutes due to no outside force to help it cool down. That and possibly fuel boil as stated before. What are you using for your fuel lines? Depending on what your using, it could be causing the lines to get too hot causing vaporlock possibly.

On the issue of red lights, I have a similar problem with red lights when pulling out of the neighborhood for college. It's because the car still needs time to warm up for me. But after getting it past the 2nd light or so, it seems to be fine.
I've a mechanical fuel pump which has regular rubber tubes going in and out.

I had similar case where it needed to warm up before it would work without an issue. I fixed that by increasing the idle RPM.
 

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I've a mechanical fuel pump which has regular rubber tubes going in and out.

I had similar case where it needed to warm up before it would work without an issue. I fixed that by increasing the idle RPM.
It could be those rubber lines in general? I run metal fuel lines to the pump and to the carburetor for a bit where I then transfer to rubber to fill the gap between.
 
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