Verify what the actual temperature is and when and under what conditions this happens. Did it just start doing this, did you just get the car and this is a surprise problem? Lots of things come to mind. Tell us more about what's going on and the specifics of your car and what you have done about it so far. Many folks will chime in.
p.s., welcome to VMF

 

Thanks for the welcome. Where/How do I verify actual temperature? I have an electronic temp gun but not 100% sure where to point it. Just got the car so this is surprise problem. While flushing the radiator and letting the car idle, it started to overheat close to 40 minutes into the flush.

 

One way to check coolant temperature is to take the radiator cap off (when cool of course) and put a meat thermometer then start the car and let it idle. It should give you an idea of the actual temperature. If you do this, keep a rag around the thermometer in case you get sudden burp of antifreeze.

 

IR temp gun, get a reading from the block, heads, thermostat housing, top of radiator or with the cap off, the coolant and various sections of the radiator fins. You can also get a reading from the rubber hoses going into and out of the radiator but those won't be as accurate however the bottom hose should be cooler.

 

Ah yes, someone else;s problem they have now sold you...I like to start with a mechanical temp gauge installed and see what that reads, Does it overheat while driving, or when your at lights or stuck in traffic? What temp is it actually getting to? So many things to verify, you are going to have to google some things to spot check first. If its had the heads off recently, make sure the head gaskets were not put on backward, you do this by looking at the tab of gasket protruding from the front of the head-are they stock or alum aftermarket heads? Is the fan installed correctly, is it close enough to the radiator? What type of fan blade and do you have a shroud? When you flushed it, did a lot of gunk come out, or it seems pretty clean? Can you get good heat from the heater indicating its not clogged up? verify the heater hoses are run to the correct spot off the pump and intake manifold..A new 180 degree thermostat is cheap and easy to install-again, correctly installed-dont overtighten the housing bolts or you risk cracking the housing...Engine timing can affect things as well. The waterpump could be the issue, but I doubt it..Can you post some good pictures of your engine nay and fan?

 

Hi. I'll answer what I can. It seems to overheat while idling or driving. Not sure what temp it's actually getting to, I've just been going off of the instrument panel and the coolant coming out the overflow tube on the side of the radiator. Attaching more pics. I believe you can see the head gasket and the heads are aftermarket.

When I flushed the radiator, it was fairly clean, not a lot of gunk came out.

I haven't verified the heater hoses, I'll try and do that today or first of the week. Is the recommendation to change the thermostat from 160 to 180?

 

Ok, let's start at the beginning.... what is your picture supposed to be showing us? What are the details of your car and issue? What makes you think it's overheating? Why did you "flush" the cooling system?

 

The picture is the timing wheel (not sure of correct name). Sorry, I should have pointed that out. I think it's overheating because after about 40 minutes of being idle/driving, the temp gauge in the instrument panel moves past the H mark and the coolant starts to flow through the overflow hose. I flushed the radiator since we just got the car and thought it couldn't hurt.

 

The last thing you want to do is start shotgunning parts at the issue. If it overheats at an idle it's usually an airflow issue, at speed, water flow. Not saying there isn't some junk in that radiator, but let's verify everything else first.

 

Ok, nice stock looking engine bay so far! Yes, that radiator looks pretty clogged up-can you find a radiator shop around you that can "hot tank" it? Its ok to start out with a desire to learn and work on your own car, some later in life than others of us I like NPD for my mustang parts and places like Orielys or rock auto for mechanical parts. You should order from NPD the original ford shop manual, this has all the info needed to work on the car. As a bonus, you have utube, google, and VMF to help learn and understand. Stay away from cj pony parts, just mine and a lot of others opinion......Be sure to use the search function on the site as well as you can learn a lot from previous posts by others. The part you first showed is the harmonic dampener or balancer, clean off the outer edge with some sandpaper to find the timing marks on it, then mark them with some white paint so the lines are clearly visible. The bump out thing behind it is the timing chain cover pointer, thats where you aim the timing light and see how it lines up with the marks on the damper to set your timing with a timing light tool, which you need to have and learn to use. Anyways, do not use a 160 thermostat, use the one ford listed for your car which I think was 180, get the service manual and it will list it..your heater hoses are not hooked up to the heater core ruh roh, more work, probably done to by pass a leaking heater core...more work and research on a job you can tackle yourself if you are physically able and so desire. You can spend a lot of money real quick paying people to work on your car so hopefully, you want to do the work yourself! That fan is adequate at best, you can get a bigger better 5 blade oem style that will draw more air-do not get a cheap speed shop aluminum or fiberglass fan. I would upgrade to a stock fan shroud setup which can help. Again, NPD has it and the brackets. Add your location to your avatr and maybe you can meet so,e other VMFers around where you live that you can meet up with or they may swing by to assist! Ithink the radiator is a big part of your issue at the moment though..and I am not a fan of aluminum after market radiators or electric fans for what thats worth. Keep coming back and let us know you got it resolved! Best of luck!

 

Radiator looks pretty clogged up. As others have suggested, see if there is radiator shop around that will go through it. I would do a really good coolant flush again seeing that much gunk in the radiator.

A factory style 6-blade fan, fan shroud and a thermal-fan clutch would be the way to go. My 67 has factory A/C and has never overheated even with the A/C full on in the summer here in AZ. My 67 has the factory 7-blade fan, fan shroud and thermal-fan clutch.

 

Are we even sure that you are overheating at this point? Just because the 57 year old gauge says it's running hot and some coolant went into the overflow, that doesn't necessarily indicate to me at least that you are overheating. I think your best bet, as mentioned above, would be to check yourself, or have a buddy check for you, the temperature at multiple different points on the engine with a temp/heat gun. That, and I would, as also mentioned above, install an aftermarket electrical or mechanical water temperature gauge so that you can always know exactly what temperature you're at instead of going off the gauge that's now almost 6 decades old. Also, as others have mentioned, check to make sure your thermostat is installed the correct way and that you have the proper one in there to begin with. Things like an electrical or mechanical gauge, thermostats and so forth are usually quite inexpensive in that they're less than $20 a piece. How does your air cleaner look? How big is it? Is it providing enough air to the carburetor or is it clogged and/or smaller in size? I personally like an aluminum radiator better than the original style, and then I also like to add electric cooling fans to the car as I think they are much better at cooling than the stock style fan. Good luck!

 

Holy smokes, that radiator is FULL of garbage 😳 no wonder it’s running hot.
I’d definitely start with that.

 

I've seen way fuller...lol.

 

I would start by sending out the radiator and flush the block and heater with a hose


ken

 

Check your radiator cap to make sure it's holding pressure. What is the pressure rating of your cap?
The radiator is not supposed to be filled all the way to the top. It should just cover the fins. The empty room at the top allows for expansion as the fluid heats up.
Do not assume the reading on the temp gauge in the dash is correct. It might be, but you need to verify.

From the picture, your radiator is filled with junk. I would pull and get it cleaned.

 

Wow. I'm overwhelmed with the suggestions. Thank you all for the quick replies. Rather than reply to each and make it fragmented to read, I'll try and quote and reply in a single thread.

Redneckgearhead - Ok, that's called a harmonic balancer. If it takes 40 minutes of idling to overheat, it doesn't seem serious. I'd check the ignition timing, check for a minor vacuum leak, verify you're not over filling the radiator. Pressure test the cap, you can rent a tester from your local big box auto store.

Thanks for the correct terminology. I have a timing gun on order and should arrive tomorrow. I whould be able to check the ignition timing from there. Where am I checking for vacuum leaks? I'll get the cap tested as well.

Redneckgearhead - The last thing you want to do is start shotgunning parts at the issue. If it overheats at an idle it's usually an airflow issue, at speed, water flow. Not saying there isn't some junk in that radiator, but let's verify everything else first.

Fair enough on the shotgun issue. Moment of weakness and just wanting to rip it out and start over. . I did notice while it was idling and I would rev the engine at higher RPMs, the water "seemed" to flow decently.

Geicoman58 - Ok, nice stock looking engine bay so far! Yes, that radiator looks pretty clogged up-can you find a radiator shop around you that can "hot tank" it? Its ok to start out with a desire to learn and work on your own car, some later in life than others of us I like NPD for my mustang parts and places like Orielys or rock auto for mechanical parts. You should order from NPD the original ford shop manual, this has all the info needed to work on the car. As a bonus, you have utube, google, and VMF to help learn and understand. Stay away from cj pony parts, just mine and a lot of others opinion......Be sure to use the search function on the site as well as you can learn a lot from previous posts by others. The part you first showed is the harmonic dampener or balancer, clean off the outer edge with some sandpaper to find the timing marks on it, then mark them with some white paint so the lines are clearly visible. The bump out thing behind it is the timing chain cover pointer, thats where you aim the timing light and see how it lines up with the marks on the damper to set your timing with a timing light tool, which you need to have and learn to use. Anyways, do not use a 160 thermostat, use the one ford listed for your car which I think was 180, get the service manual and it will list it..your heater hoses are not hooked up to the heater core ruh roh, more work, probably done to by pass a leaking heater core...more work and research on a job you can tackle yourself if you are physically able and so desire. You can spend a lot of money real quick paying people to work on your car so hopefully, you want to do the work yourself! That fan is adequate at best, you can get a bigger better 5 blade oem style that will draw more air-do not get a cheap speed shop aluminum or fiberglass fan. I would upgrade to a stock fan shroud setup which can help. Again, NPD has it and the brackets. Add your location to your avatr and maybe you can meet so,e other VMFers around where you live that you can meet up with or they may swing by to assist! Ithink the radiator is a big part of your issue at the moment though..and I am not a fan of aluminum after market radiators or electric fans for what thats worth. Keep coming back and let us know you got it resolved! Best of luck!

I did some research on which place best for parts and NPD seemed to be the favorite. I'll clean up the harmonic balancer this week when the timing gun comes in. I'll need to check again but I think 6 degrees was the correct setting for it. Sounds like 180 thermostat is the unanimous choice. Since it's cheap and easy enough to change out, I'll do that soon as well. I'll google/youtube the heater hose comment. I'm unfamiliar with that and where the connection goes. Fan blade - I was thinking a 5/6 fan blade and then adding a shroud. I think I was holding off on that since I wasn't sure if I was going to change out the radiator or take it to a shop to get it cleaned out.

GradyStang - Are we even sure that you are overheating at this point? Just because the 57 year old gauge says it's running hot and some coolant went into the overflow, that doesn't necessarily indicate to me at least that you are overheating. I think your best bet, as mentioned above, would be to check yourself, or have a buddy check for you, the temperature at multiple different points on the engine with a temp/heat gun. That, and I would, as also mentioned above, install an aftermarket electrical or mechanical water temperature gauge so that you can always know exactly what temperature you're at instead of going off the gauge that's now almost 6 decades old. Also, as others have mentioned, check to make sure your thermostat is installed the correct way and that you have the proper one in there to begin with. Things like an electrical or mechanical gauge, thermostats and so forth are usually quite inexpensive in that they're less than $20 a piece. How does your air cleaner look? How big is it? Is it providing enough air to the carburetor or is it clogged and/or smaller in size? I personally like an aluminum radiator better than the original style, and then I also like to add electric cooling fans to the car as I think they are much better at cooling than the stock style fan. Good luck!

Pretty sure it's overheating. It's fine for the first 30 minutes or so and then I notice the smoke coming out from the hood which ends up being the coolant steaming out of the radiator overflow tube. Am I mistaken that it's a sign of overheating? I'll get the temp gun on it soon after putting in the spring in the lower radiator hose. Air cleaner is new and super clean. I just had it off for the picture. Where do you connect the electric fan too if you go that route? I guess I'm under the impression that with the tiny fuse panel, there's not much more you can add without changing that out as well.

Daves67ss - Check your radiator cap to make sure it's holding pressure. What is the pressure rating of your cap?
The radiator is not supposed to be filled all the way to the top. It should just cover the fins. The empty room at the top allows for expansion as the fluid heats up.
Do not assume the reading on the temp gauge in the dash is correct. It might be, but you need to verify.
From the picture, your radiator is filled with junk. I would pull and get it cleaned.

Pressure rating is 13 lbs. I've seen some suggest more and other say it's enough. Thanks for pointing out how full the radiator should be. I'll keep that in mind. Consensus says to pull it and get it cleaned. Will probably go that route first and see what it does.

Again, thanks all for the suggestions. I'm youtubing and googling like a mofo but it's great to have such quick feedback.

 

I’m guessing that the Seller mentioned nothing about an overheating issue,……did you test drive the car?

 

Of course not but I'm trying to not focus on that.

 

I’d say get a new radiator. Check/change thermostat. make sure fan is 1/2 into shroud. You can get aftermarket shroud from Jegs or summit. Let run and ensure circulating.

 

Coolant coming out of the overflow IS an indication that it's overheating, but it could be a sign of an over full cooling system. It needs some room for expansion.

 

^^^^ Agreed.

To the OP, are you sure that it's coolant that's steaming and coming out of the hood? Not trying to say necessarily that it 100% isn't, that being said it could be oil or other engine fluids that are on something hot like the intake, headers or exhaust and so forth. An electric fan is attached to the radiator either with ties, clamps or some sort of mounting system and typically has a small relay next to, or close to your starter solenoid. No need to wire it underneath the dash where the fuse panel is under there, it runs off it's own relay and has typically an inline fuse holder next to it that you can check as well. I personally like the electric fans because you can wire them how you want in that, depending on the relay, you can have them turn on and off at a set temperature, or adjust the preset temperature to whatever you want, as well as you can add an override or manual switch inside the car so that you can turn it on whenever you want it to. I think the easiest, although the most boring route, would be to sit and wait for the car to run for the 30-40 minutes or whatever it takes for it to overheat, and monitor what happens and from where with your IR temp gun. Or go for a 20-30 minute cruise, bring the car home and sit with it idling to see what happens.

 

As mentioned by Geico...factory shop manual 1967...

SHOP MANUAL, PRINTED, 1967 MUSTANG, COUGAR, FAIRLANE, FALCON - #L-25 - National Parts Depot (npdlink.com)

192* Thermostat if you are ordering a replacement -Stant would be my choice - available through Summit....

1967 FORD MUSTANG - stant thermostat KEYWORD Parts & Accessories | Summit Racing

John

 

@fs65stang - I sent you a PM. Click on your profile thumbnail (top right corner) to retrieve.

 

Most people think that a lower temp thermostat will lower the engine temp, but it's not necessarily true.

The most common reason for overheating is lack of a fan shroud and poor airflow through the radiator. Combine that with a bit of corrosion and some mineral deposits, and over time, at idle, your engine is going to overheat.

Timing is another very common reason for overheating. Too much timing (advanced) will make your engine run hot. Too little (retarded) timing will make your exhaust and engine compartment very hot.

The thermostat opens when it reaches a preset temp, and tries to hold your engine at that temp. But if it's overheating well past the thermostat being open, the thermostat is no longer the problem. So long as it's open, it's doing the best it can, and whether there's a 5 degree or 192 degree thermostat in there, it's still going to overheat, because of inadequate cooling and problems that have nothing to do with the thermostat. A 160 t-stat or similar may delay the time it takes to overheat by a minute or two, but that's all you get from it.

The big downside to a cold thermostat is that when your cooling system is doing its job and able to hold temp at the lower thermostat setting, your oil may not get hot enough to boil away impurities. As a result, it makes sludge and mayonnaise that will clog up your engine and cause rust issues. It's a good idea to stick with the stock 192 for street use. It should not cause overheating issues.

 

I agree with the other 99% - get the rad flushed.

Nice setup though, and welcome.

 

Lots of good advice. And your response shows your willingness to learn - great.
Here's my little advice: do the meat thermometer in the radiator first. It will tell you what temperature your thermostat is opening and how hot your engine is really getting. Then check your timing and determine if you need a turn-up, both problems can lead to overheating. A little diagnostic work before staring the part-replacement efforts is always a good idea. One problem with overheating issues is determining whether it's an engine problem (bad head gasket, poor ignition, burnt value, etc) or a cooling problem (clogged radiator, worn pump, inadequate fan, etc).
And yes, get the FACTORY shop manual. I also recommend the electrical assembly manual as it has lots of exploded views with mounting hardware.
Keep us up to date, ask questions, and we'll do our best to help. Good luck.

 

Welcome to the board, this place is Great!

You’ll get it figured out.

 

I wouldn't assume the seller ever had an issue with overheating. He probably never let the car sit idle for 40 minutes.

 

I'm overwhelmed by the replies. Good stuff for sure! Concatenated email for all the replies. If I overlooked your comment, my apologies.

Palerider -
I’d say get a new radiator. Check/change thermostat. make sure fan is 1/2 into shroud. You can get aftermarket shroud from Jegs or summit. Let run and ensure circulating.

Ordering the 192 thermostat from the link that subpar63 gave me. Thanks for the link!

GradyStang - To the OP, are you sure that it's coolant that's steaming and coming out of the hood? Not trying to say necessarily that it 100% isn't, that being said it could be oil or other engine fluids that are on something hot like the intake, headers or exhaust and so forth. An electric fan is attached to the radiator either with ties, clamps or some sort of mounting system and typically has a small relay next to, or close to your starter solenoid. No need to wire it underneath the dash where the fuse panel is under there, it runs off it's own relay and has typically an inline fuse holder next to it that you can check as well. I personally like the electric fans because you can wire them how you want in that, depending on the relay, you can have them turn on and off at a set temperature, or adjust the preset temperature to whatever you want, as well as you can add an override or manual switch inside the car so that you can turn it on whenever you want it to. I think the easiest, although the most boring route, would be to sit and wait for the car to run for the 30-40 minutes or whatever it takes for it to overheat, and monitor what happens and from where with your IR temp gun. Or go for a 20-30 minute cruise, bring the car home and sit with it idling to see what happens.

Yes, 100% sure. I can open the hood and see the coolant/steam coming from the overflow tube. Thanks for the additional information on how the electric fan is wired and operates. I was working I would have to possibly change the entire wiring harness for additional electrical needs.

Scott65Coupe - I agree with the other 99% - get the rad flushed.

Hoping to get this done this week. Currently looking for a shop.

CJM68GT390 -
Lots of good advice. And your response shows your willingness to learn - great.
Here's my little advice: do the meat thermometer in the radiator first. It will tell you what temperature your thermostat is opening and how hot your engine is really getting. Then check your timing and determine if you need a turn-up, both problems can lead to overheating. A little diagnostic work before staring the part-replacement efforts is always a good idea. One problem with overheating issues is determining whether it's an engine problem (bad head gasket, poor ignition, burnt value, etc) or a cooling problem (clogged radiator, worn pump, inadequate fan, etc).
And yes, get the FACTORY shop manual. I also recommend the electrical assembly manual as it has lots of exploded views with mounting hardware.
Keep us up to date, ask questions, and we'll do our best to help. Good luck.

Will do the meat thermometer after the rad flush. Stupid question - how do I know when the thermostat opens up? I see flow in the radiator? If the cap is off and therefore not pressurizing, does that cause anything I need to account for?

Thanks all!

 

Stupid question - how do I know when the thermostat opens up? I see flow in the radiator? If the cap is off and therefore not pressurizing, does that cause anything I need to account for?

First, the only stupid question is the one you don't ask.
Yes, when the thermostat opens is when the water/coolant will start to flow into the radiator. You can also feel the upper hose - when it starts to get warm is when the thermostat has opened.
As already stated, the main reason for pressurization is to increase the boiling point of the coolant. With antifreeze, that point is higher than 212 even with no pressure.