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Hello...I have a 1973 Cougar XR-7 convertible that I love dearly, but I am really struggling with the engine overheating. I am somewhat of a novice and trying to learn as much as I can by reading posts, etc. Just a quick background on the vehicle - my Dad purchased the car new in 1973 and it's been in the family ever since. In the early 1990's, there was a supposed complete restoration done in Baton Rouge which is near the city I live in (Lafayette, LA), however the restorer turned out to be a crook who may or may not have done much to the car. The car was involved in a fender bender in 1999, at which point my Dad decided to have the engine rebuilt. The gentleman who rebuilt the motor is known in town as being a Mopar guru, and not knowing a ton about engines, I was not the best person to ensure that he did a great job rebuilding the engine. I don't know specifics, but I do know that he bored out the cylinders (which I've read can cause heating problems due to thin cylinder walls), he also changed the cam, and went from the factory two barrel to a four barrel carb. I don't know anything about the size of the radiator, but I do know that the cap says it is rated for 13psi?
Ever since the engine was rebuilt, it has had problems overheating when idling or in traffic. It also overheats / heats up even when it hasn't been running hot, but you stop the engine, let it sit - when you come back to restart it, it is hotter and doesn't start easily. There is a fan shroud, but I am not sure what type of fan is there. Fast forward to today - because I was not certain of the quality / correctness of what the restorer did in 1999 when he rebuilt the engine, I brought the car to a local restoration shop that has an excellent reputation (and I spoke with several clients who were pleased). They told me that the carb that had been installed was known to be problematic, so we switched to a new Edelbrock carb (also a 4 barrel). They also recommended I replace the old points system in the distributor to a more modern electronic system, which I did. They also said the timing was a little off, which might have made the engine run a little hotter than it should. And lastly, they changed the spark plugs and wires. Well, the engine runs much better in general after this, however, it still does the same thing. It starts beautifully when cold, but once it warms up, it does not start well, and it warms up when sitting. Drive a little bit, it cools off, but don't sit very long. I spoke with Don at West Coast Classic Cougars, and he recommended I try the replacement restrictor plate that has only a hole in it just larger than a pinhole and the windsor thermostat (rather than the cleveland one). So I made my first attempt at working on the motor, and I was able to remove the housing off the block, remove the thermostat, remove the brass restrictor plate (without damaging it), install the new aluminum plate and thermostat. At first I thought I had a great success, because I started the car, it ran great to go down the street and dump the old anti-freeze at a local garage (longtime friends who allowed me to use their disposal). I guess I forgot to mention that I drained the radiator, but I refilled it with new 50 / 50 long life anti-freeze. When I got home from the shop, I let it run in the driveway, and after a few minutes, it sounded like it was getting hot, and sure enough, the temp guage was climbing fast past the halfway point between C and H. I parked the car, and tonight when it is cold, I will check the anti-freeze level in the radiator.
When I dumped the anti-freeze, it looked fine - almost no sediment, no evidence of rust. Since I am very much a novice, I'm wondering if anyone has any suspicions. The engine runs fine on the road. If you're moving, you're OK. Any chance that I should suspect the water pump, or could this be a fan issue? I kind of remember the restorer from 1999 mentioning that he was installing some type of fan that would adjust to the rpm of the engine and blow sufficient air at low rpms, but I don't know what this would be called. A clutch fan maybe? But whatever is going on, it isn't a minor overheat, at least I don't think so. I can't say enough the difference in how the engine starts from when it is cold to when it is hot. They seem like two different engines. Any insight / advice would be greatly appreciated. I should mention that it is 100F today in Lafayette, LA, so I'm sure that doesn't help! Thanks, Tyson
 

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It should run at 12 - 3/4 of the temp guage on a 100 degree day normally. The radiator coolant level needs to be about 1/2" below the bottom of the cap when full. The engine should heat up after it is turned off.

In your climate it is a good idea to be sure the fan clutch is new every 4 years or threreabouts.
 

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You might be getting heat soak into the old starter, which makes it difficult to restart

When you say it overheats in traffic, what is it doing? Is it spewing out steam?

As Royce pointed out - it isn't overheating until the needle is just about off the gauge. I live in an area where temps get around 100F all the time and my modified Cleveland runs at 3/4 on the gauge all the time but it doesn't overheat and boil it's coolant

If the temperature continues to rise all the time until it is nearly off the gauge your fan might be defective - and if it then doesn't cool down when you are moving through the air - you will generally find that your radiator is blocked.

Ford Australia did away with clutch fans on Clevelands and put in a spacer because they were more reliable and better for cooling in our hot climate
 

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Discussion Starter #4
Hi Leon...It isn't boiling over its coolant. I hate to show my ignorance, but when you say put in a spacer, what does that mean? And is there a starter that would be recommended for the 351C? And again, to show my ignorance, is there a water pump and radiator that are ideal for the 351C or ones that work especially well in warm climates? Thank you again for the feedback! Tyson
 

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Just my two cents. When I rebuilt my engine I installed a mild race cam,changed from 2 to 4bbl, and bored out .030. I had problems with overheating like you. On the advice of some knowledgable ford guys, I changed out the original radiator to a 3 row core. That fixed my overheating.
 

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Discussion Starter #6
How can I tell which radiator I have, and where did you get your 3 core radiator replacement? Thanks, Tyson
 

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How about the thermostat? My 351C ran hot with a 180 thermostat. I put a stock 195 degree one in and never had a problem since. I have 4v heads a big cam and a demon carb with dual electric fans on a stock radiator and when its 105 degrees out I stay around 210 degrees
 

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Surround yourself with someone who's good at working on cars and is trustworthy. Make sure all systems are good. Good mechanic will know what to do.
Now, about all these Cleveland overheating posts I've noticed-
I really don't know what the problems are people seem to be having. Years ago I converted a Cyclone from a 351W w/auto to a 351C 4V and 4 speed. Mild cam, headers,clutch fan and 3 core radiator. All systems were good. It ran so cold I had to block off 2/3 of the radiator in the winter for it to come up to 160 degrees. In the summer rarely did I see 200.When so within 1/2 block it was back down to 160-180. And it gets hot in Bakersfield, Ca.
I ran without a thermostat after trying a 160 unit. Took the heads off for a valve job after about 20,000 miles and the cylinders looked I had just honed them. Point being, in the REAL WORLD, I didn't wash down the cylinder wall from running to cold.And it never used a drop of oil.Seek out good help.
 

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To check the number of rows in the radiator
- remove cap
- drain coolant until you can see the radiator tubes

A 3 row radiator will have 3 tubes visible in each horizontal row of tubes. A 3 or 4 row radiator is better

Here is a three row radiator

http://www.mustangsunlimited.com/itemdy00.asp?T1=IR388+01

The spacer replaces the clutch fan and goes between the pulley and fan to position the fan in the correct position in the shroud

http://www.mustangsunlimited.com/itemdy00.asp?T1=FSV8+01


There is a lot of opinion about cooling but:

. unless the engine is heating up and going off the scale on the gauge, the engine is working within its tolerances - some run hotter than others and horsepower generates heat (as does crappy metallurgy)
. a clear radiator is essential for proper cooling (ie no tubes are blocked off) - if it is blocked the engine temp will continue to increase and eventually the coolant will boil
. a properly functioning thermostat is essential for proper cooling - if it doesn't work then the coolant will boil and you will get steam out the overflow
. you need a fan to keep an engine within operating temperature when the airflow through the radiator is insufficient to cool the engine
. a shroud will increase the efficiency of cooling at low speeds
. an engine will find its own operating temperature, irrespective of the thermostat being used
. when the ambient air temperature is high the engine will run hotter as the cooling differential through the radiator is narrower

One of the old wives tales is that 160 degree thermostats don't allow the the radiator to cool engine because the water is flowing through the radiator faster. Once the thermostat is open the water flow is a function of the water pump speed and the capacity of the radiator. Ford Australia ran 160 degree thermostats in Clevelands in hot climates for many years. A 160 degree thermostat will not allow an engine to warm up to an optimum operating temperature, if the ambient temperature is around 50 degrees F. (sorry - can't find the work that was done by one of the Australian Ford magazines that checked all these options out for a Falcon XD with 351C)
 

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Discussion Starter #10
Hi Leon...I am strongly considering changing the radiator. I have no idea how old that radiator is (whether or not it was replaced in 1999 after the car accident). I also wanted to ask about the fan. I believe I have a clutch fan, but I took some pictures to try to be sure. The fan has a metal disc in front of it (between the fan and the radiator). There is a space between the fan and the radiator, and I noticed that while the fan is mostly under the shroud, there is about 1/2 of an inch that sticks out from under the shroud. I am going to attach some pictures. I am wondering if I should first try the spacer (before replacing the radiator with a 3 row radiator) to see if the spacer makes a significant difference. Cougar 010.jpg
 

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Got my 3 core replacement radiator 2 weeks ago at Advanced Auto, for $266.00. Made all the difference in the world. It is nice to run the air conditioning with out worrying about over heating. 351 4v 1970 XR7.
 

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It should run at 12 - 3/4 of the temp gauge on a 100 degree day normally. The radiator coolant level needs to be about 1/2" below the bottom of the cap when full. The engine should heat up after it is turned off.

In your climate it is a good idea to be sure the fan clutch is new every 4 years or there abouts.
No clutch in 73, just a spacer and flex fan.

 

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Welcome to the forum Tyson. The picture posted of the engine fan shows it has a fan clutch attached to it. Its the aluminum piece with the fins on it in front of the fan. If you have not replaced the clutch I would do so. Our climate in south Louisiana can be brutal in the summer with 90-100 degree temps and 90% humidity a common daily occurance. A 3 core radiator is a must especially if the A/C you are running is functional. You may want to check that the radiator cap is in good condition also. A faulty radiator cap will not keep the cooling system under pressure. This can result in over heating problems. I run a 351 cleveland in my 1970 Cougar and have had my engine rebuilt with .030 bore and run the factory restrictor plate with a 195 degree t-stat and the car runs fine with a operating temp of 185 degrees after warm up. My car is a factory no a/c car so I have no ac condenser in front of my radiator.

Scott
Gretna, La
 

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Discussion Starter #14
Hi...when you bought your radiator at Advanced Auto, did you just tell them make and model of the vehicle, then figure out which one went with your engine? Do you remember the name / type of the one you purchased? Thanks, Tyson
 

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Discussion Starter #15
Hi Scott...good to hear from a local guy! Do you use a fan with a spacer as others have described? Thanks, Tyson
 

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Hi Leon...I know I'm going to have to find a good mechanic that I trust to work with, but how do you remove the fan with the shroud in place? Do you remove the shroud first, and if so, how do you remove it? Thanks again, Tyson
 

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Tyson,

Yes, I do use the fan with a spacer. I would try using the spacer that Don at West Coast Classic Cougar posted on this thread. Glad to see another Louisiana Cougar owner on this forum. Couple of us here in the New Orleans area post on this forum. I believe someone in the Lake Charles area also is a forum member. At one time many years ago I lived and attended U.S.L (Rajun Cajuns) in Lafayette, La. This forum has a great deal of information and knowledge you can put to use on the cougar you have. Try using the search feature to do some research involving people with similar problems. The people on this site harbor a wealth of knowledge that can make working on the cougar you own a much more enjoyable experience. Good Luck!

Scott
 

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Tyson - sorry to take so long to respond I have been travelling

To remove the fan and fan clutch
- remove the radiator shroud from the radiator so you can get better access to everything
- undo radiator hoses at radiator
- unbolt radiator brackets and remove radiator
- remove shroud
- unbolt fan clutch from pulley - it is a slow job where you have to undo the bolts as far as they will go, pull the clutch away from the pulley to get more space for the bolts to come out and then undo the bolts until the fan clutch comes off
 

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Discussion Starter #20
It doesn't sound too rough. Do you think I should change the water pump while I am at it? If I'm going to go through changing the radiator and fan, would it make sense to change out the water pump as well? Thanks, Tyson
 
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