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25 replies

Cannot get my Pantera to cool

johnek74panterajohnek74panteraMember
I know I'm opening up a hornets nest here but I'm getting very frustrated. I have read every cooling post in the forum probably twice and there is a wealth of excellent information. I'm going to the well once more to see what I can find. My 1974 L was purchased a year ago february. The car had not run since 1986 however was mothballed very well. The rad was shot so I put a new custom made "Wizard" double pass with twin spal sucker fans in. I have "burped" the car probably 8-10 times now both front and back. I've started it on the flat, waited 5 minutes, jacked it up, bled air out the rad, added coolant etc. etc. etc. I have gotten a fair bit of air out of the system. What happens each and every time is this. After I place the pressure cap back on, the car will idle for about 10 minutes with the temperature slowly inching up. I continue to check the rad hoses as it pauses around 190. They are cold. It inches up towards the first mark past 190 and the hoses are still cold. Eventually it gets to the first mark past 190, the hoses go stinking hot and the puke tank passess about a gallon of coolant all over the floor and I shut er off. I'm thinking now that I have a thermostat issue but I'm open to any and all suggestions. I've gone through this scenario probably 6 times now and it's gettin damn expensive for the coolantSmiler)) Oh wise and wonderful forum…what sayest thow….
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J jb1490Member
If the heads were off recently, one or both head gaskets could have been installed backwards. Usually, the overheating occurs a little sooner than the your stated 10 minute time.

In the pic below, the red arrow on the left points to a large hole in the head gasket, and the red arrow on the right points to two small holes (some gaskets may only have one small hole instead of two).

The large hole goes to the REAR of the engine. The head gasket in the pic was installed BACKWARDS.

The teal arrow is pointing to a square corner of the head gasket. That square corner is ALWAYS at the front of the block. This makes it very easy to tell if the head gasket is installed correctly.

With iron heads, that square corner sticks out. With aluminum heads, that square corner may be covered by the head, but it is not covered by the block. Using your fingers, you can feel for the gasket. It's under the overhanging edge of the aluminum head.

John

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George PGeorge PAdmin.
When the head gasket is installed backwards the engine makes an interesting gurgle & surge sound as its running.

The other possibility is you have a Weiand or Milodon water pump in which the recirc passage has not been drilled out. That usually results in a pulsating temp gage as the engine warms up. The gage swings quickly from cold to hot, and then back to cold again. Over & over several times until the engine reaches operating temp.
johnek74panterajohnek74panteraMember
quote:
Originally posted by jb1490:
If the heads were off recently, one or both head gaskets could have been installed backwards. Usually, the overheating occurs a little sooner than the your stated 10 minute time.

In the pic below, the red arrow on the left points to a large hole in the head gasket, and the red arrow on the right points to two small holes (some gaskets may only have one small hole instead of two).

The large hole goes to the REAR of the engine. The head gasket in the pic was installed BACKWARDS.

The teal arrow is pointing to a square corner of the head gasket. That square corner is ALWAYS at the front of the block. This makes it very easy to tell if the head gasket is installed correctly.

With iron heads, that square corner sticks out. With aluminum heads, that square corner may be covered by the head, but it is not covered by the block. Using your fingers, you can feel for the gasket. It's under the overhanging edge of the aluminum head.

John


heads haven't been off. 13,680 original miles so I don't think that's the culprit
johnek74panterajohnek74panteraMember
quote:
Originally posted by ItalFord:
I would begin with the thermostat. Make sure it its a robertshaw 333 and the pressed in brass plug is in place below the stat. I would use a 180 degree. If that doesn't do it. The head gaskets could be the culprit also. Try the easy things first.


I certainly agree with the logic of the easy things first. I will replace the thermostat and start there...
johnek74panterajohnek74panteraMember
quote:
Originally posted by George P:
When the head gasket is installed backwards the engine makes an interesting gurgle & surge sound as its running.

The other possibility is you have a Weiand or Milodon water pump in which the recirc passage has not been drilled out. That usually results in a pulsating temp gage as the engine warms up. The gage swings quickly from cold to hot, and then back to cold again. Over & over several times until the engine reaches operating temp.


Stock water pump on the engine with 13,000 original miles so I don't believe there is an issue with the recirc passage. The temp guage would never pulsate…slow warm up to 190 ( about 10 minutes) then sit there and slowly climb to about 225 where it would start to puke out the overflow line…..
dougmdougmMember
If you have the original 40 year old thermostat in there and the car sat for more than 20 years there is a good chance the thermostat is not operating properly. Might I suggest if you are going to go to the trouble of pulling the housing off to remove the old thermostat, you might as well just install a new one and be done with it.

Doug M
italforditalfordMember
Running without a stat will take a long time for the engine to warm up. Once it reaches operating temp it will continue to climb until it pukes. This will occur more quickly if the car is stationary. Just install a new stat and go from there. Since you mentioned that its the original engine and water pump is there a chance there is corrosion in the engine and pump that impedes its performance? Investigate.
panteradougpanteradougMember
I have found that often on the Pantera, the cap on the tank is defective or not sealing properly.

I helped out a couple of other Pantera owners who couldn't find the problem and it was a bad cap.



Others have seen this as well even with new aftermarket caps.

I pressure test everything now. For one thing the pressure tester helps push air pockets out of the system.

I also pressure test the new cap. I have had new ones that were already defective.

The cap and the system should be pressure tested to 16 psi. The cap should be a 16 psi cap.



There are some new caps that will not seal properly on the seat in the neck of the pressure tank.

In that scenario, the cap and the system will check ok at 16 but still have a problem.

If you have one of those caps that is not long enough to reach the seat in the tank, you probably can double up the gasket by gluing it on with crazy glue. The Loctite brand works well and is an industrial and not a hobby glue.



This scenario is a unique situation to the Pantera and is not looked for by service technicians unfamiliar with the car. They just don't expect to see this.

A pressure testing kit is a good investment on a Pantera.



When my SHO was new and still under warranty, the car would overheat in traffic. It was towed in and serviced by a Ford dealer.

They changed the thermostat and it did it again.



I finally started testing the car myself and it turned out that the cap was defective and they never tested, looked at or replaced it. It was still the original cap from new.

I pressure tested the cap. Hissed away like crazy. That was the entire problem all along.

The techs just don't look for this.
johnek74panterajohnek74panteraMember
quote:
Originally posted by PanteraDoug:
I have found that often on the Pantera, the cap on the tank is defective or not sealing properly.

I helped out a couple of other Pantera owners who couldn't find the problem and it was a bad cap.

Hi Doug. I suspected the cap as well. I have found a NOS Motorcraft RS40 which is on it's way. In the meantime the list recommended a stant 10230 which I installed yesterday. It does not allow any coolant to escape which the old one did. I bought a pressure tester for the system, but there was not one attachment that would fit my system. How did you manage to find a cap to fit your system for pressure testing?

Others have seen this as well even with new aftermarket caps.

I pressure test everything now. For one thing the pressure tester helps push air pockets out of the system.

I also pressure test the new cap. I have had new ones that were already defective.

The cap and the system should be pressure tested to 16 psi. The cap should be a 16 psi cap.



There are some new caps that will not seal properly on the seat in the neck of the pressure tank.

In that scenario, the cap and the system will check ok at 16 but still have a problem.

If you have one of those caps that is not long enough to reach the seat in the tank, you probably can double up the gasket by gluing it on with crazy glue. The Loctite brand works well and is an industrial and not a hobby glue.



This scenario is a unique situation to the Pantera and is not looked for by service technicians unfamiliar with the car. They just don't expect to see this.

A pressure testing kit is a good investment on a Pantera.



When my SHO was new and still under warranty, the car would overheat in traffic. It was towed in and serviced by a Ford dealer.

They changed the thermostat and it did it again.



I finally started testing the car myself and it turned out that the cap was defective and they never tested, looked at or replaced it. It was still the original cap from new.

I pressure tested the cap. Hissed away like crazy. That was the entire problem all along.

The techs just don't look for this.
johnek74panterajohnek74panteraMember
quote:
Originally posted by ItalFord:
Running without a stat will take a long time for the engine to warm up. Once it reaches operating temp it will continue to climb until it pukes. This will occur more quickly if the car is stationary. Just install a new stat and go from there. Since you mentioned that its the original engine and water pump is there a chance there is corrosion in the engine and pump that impedes its performance? Investigate.


The car was put away with inhibitors and during it's "rebirth" as much as possible was inspected and everything looked clean. Short of a tear down I don't know how else to check. Any of the product which has boiled over is clean.
jag13catjag13catMember
John;
From your description, it sounds as if some restriction remains in the system. I agree with the previous posts - verify proper thermostat (article attached) and proper cap fitment.
Have you backflushed the cooling system or inspected the cooling tubes. Was the heater opened when operating the engine.
What is overflowing will be clean because that is boiling the coolant to the top, leaving potential rust or deposits at the lowest point.
I would be inclined to pull the hose connections where the coolant tubes from under the body connect to the coolant tubes going to the radiator.
Just my 2 cents.

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forestgforestgMember
220 degrees is not hot enough to be considered overheating. If it is puking from the overflow tank at 220 then you just have the tank too full.
How are your fans controlled? Have you verified that the blades are on the correct way and that they are turning the correct way. I do not consider my car overheating until it gets above 230. Even then it does not puke coolant.
panteradougpanteradougMember
According to the 50/50 coolant chart, boiling point in a 16 pound system is 260 degrees F.

That's what I am using. Don't go higher.

With most of the current cars while in traffic, I get nervous at around 250 although few will show a numerical gauge. The vast majority will just show that the temp is reaching the maximum level of the "NORMAL" range. 250 is around the N where it says NORMAL.

I think the manufacturers got tired of answering questions about why their car was running hot and what's wrong with it so they took the numbers off of them.

220 is on the low end of normal operating temperatures.

235-240 is what I would like to see the maximum high be and should not be a problem at all if the system is healthy and operating correctly. This still gives a 20 degree safety factor for boiling over and is fine for me. That's for traffic and the temps should drop with the car in motion.

If someone is having boiling over issues at less than 260, simply put, the system is not holding pressure properly.

With just pure water the boiling point would be much lower. I'd have to check the chart to see what it would be exactly.
Last edited by panteradoug
jfb05177jfb05177Member
here is a boiling point chart for water.

I have been thinking about how I plan to go with my coolant system. One thing I was looking at is water swell. For the swing from 32 to 212F, the water volume will increase about 5%. I believe the Pantera system holds 28 quarts so that means the tank air volume needs to be about 1.4 quarts

edit;
does any one know the volume of the over flow tank?
just a quick though, the free volume in the over flow needs to be about twice of the coolant swell to limit the air space pressure to ~15 psig.

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panterawanabepanterawanabeMember
quote:
Originally posted by forestg:
220 degrees is not hot enough to be considered overheating. If it is puking from the overflow tank at 220 then you just have the tank too full.
How are your fans controlled? Have you verified that the blades are on the correct way and that they are turning the correct way. I do not consider my car overheating until it gets above 230. Even then it does not puke coolant.


I agree, when my car is at 220 which is most of the time I have checked with a temp reader and the engine itself is just shy of 70 degrees C. I think your overflow tank is just full and cannot take the expanding coolant. Unless you have had overheating issues in the past I would just drive it and see how it goes. I am sure you a smart enough to know when it is getting too hot before it blows it cool.

As a side note just buy a infra red temp reader and check. They are cheap and make a great laser gun for the kids(and adults afterwards!
tsolotsoloMember
quote:
Originally posted by JFB #05177:

does any one know the volume of the over flow tank?
just a quick though, the free volume in the over flow needs to be about twice of the coolant swell to limit the air space pressure to ~15 psig.


My car with Fluidyne radiator holds 5 gallons. I know this for a fact as I filled it multiple times. The overflow tank measures approximately 4-1/2"x15-1/2". Subtracting a 1/16" in all directions for wall thickness leaves 4-3/8"x15-3/8". Convert to decimal 4.375"x15.375". The volume = 2.1875x2.1875x3.14x15.375 = 231.13cubic inches. A gallon of water is 231 cubic inches so the overflow tank will hold a gallon at max capacity. I fill mine to about half way which allows for about 1/2 gallon of expansion. In case you did not know the overflow tank is vented to atmosphere, it does not hold pressure.

Steve
johnek74panterajohnek74panteraMember
quote:
Originally posted by JAG13CAT:
John;
From your description, it sounds as if some restriction remains in the system. I agree with the previous posts - verify proper thermostat (article attached) and proper cap fitment.
Have you backflushed the cooling system or inspected the cooling tubes. Was the heater opened when operating the engine.
What is overflowing will be clean because that is boiling the coolant to the top, leaving potential rust or deposits at the lowest point.
I would be inclined to pull the hose connections where the coolant tubes from under the body connect to the coolant tubes going to the radiator.
Just my 2 cents.


Definately a restriction. I pulled the thermostat tonight. First off, it's the wrong one. Secondly, it will not open. Tried it in boiling water…nothing..so everything has been closed up the whole time. I'll try and locate a proper thermostat and go from there. Will be checking tomorrow to see if the restrictor plate is in the block.
johnek74panterajohnek74panteraMember
quote:
Originally posted by forestg:
220 degrees is not hot enough to be considered overheating. If it is puking from the overflow tank at 220 then you just have the tank too full.
How are your fans controlled? Have you verified that the blades are on the correct way and that they are turning the correct way. I do not consider my car overheating until it gets above 230. Even then it does not puke coolant.


I tried doing as recommended in the manual which was having the overflow tank 1/2 full to start. I posted in another response that I think I have found much of the problem in that I pulled the thermostat today and firstly, it is an incorrect thermostat and secondly it wasn't opening at all so that's a huge part if not all of the problem. My fans run off of the battery through a relay and are temperature controlled and yes I have checked and they are going the correct way. I'll keep ya'll posted Smiler)
johnek74panterajohnek74panteraMember
quote:
Originally posted by PanteraDoug:
Glad that you found the problem. A thermostat is the simplest issue.

I fill the tank about 1/3 to 1/2. Works fine that way.

Check the radiator cap. That's cheap insurance too.


just won an ebay auction for a NOS RS40 cap so that's a good thing. Presently have a Stant 10230 which I bought as an interim measure awaiting the RS40. The cap that was on ( RS62) I believe was faulty as well …..Smiler)) Lots of fun...

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