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Overheating Issues - Water Pump?

  • Thread starter Thread starter Dan Benavides
  • Start date Start date Jun 26, 2017
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Dan Benavides

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Jun 26, 2017
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Jul 16, 2017
#21
  • Jul 16, 2017
  • #21
karthief said:
Explain a lot of pressure, 16lbs is not a lot of pressure, you should be able to squish the upper hose with the cap on and system hot, engine running. Start by pulling you t-stat and test it in a pot of water on the stove, a meat temp gauge will work, just don't tell your significant other what your doing, some frown on using kitchen tools around automotive parts.
If your t-stat checks out have your radiator checked out.
This is contingent on other parts of your cooling system operating correctly
Click to expand...

I've replaced the thermostat 3 times already. The one in the car now is a fail safe. I would think it should be fine.

The radiator is an EBay 3 row aluminum radiator with two electric fans. Could it be possible that this radiator isn't sufficient?
 

General karthief

wonder how much it would cost to ship you a pair
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Jul 16, 2017
#22
  • Jul 16, 2017
  • #22
Ebay anything does not impress me, does the radiator have a name? What are the cfm on the fans? 200 and even 215 degrees in hot weather in traffic with the air on is not unusual,
I test all my t-stats before install, I have 4 or 5 brand new that don't open at the right temp (stant brand included).
Start the car cold with the cap off, watch the for coolant flow as the system heats up, as you know it should increase with temp
When it reaches 180-190 squeeze the upper hose to push some coolant out so you have some room below the top of the radiator, raise the rpms being careful not to blow hot coolant on yourself, does the flow increase significantly?
 

2000xp8

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#23
  • Jul 16, 2017
  • #23
I didn't see if you answered the question about when it runs hot at idle and in traffic? On the highway?
I also didn't see where you said how you are getting the reading of 230 degrees, stock gauge?
Upgraded alternator?

I wouldn't have replaced the water pump if it wasn't seized or leaking and if I did it would have been with the ford racing stock replacement, not a high flow one.

While i'm not really a fan (no pun intended) of electric fan swaps on foxes, I really dislike it when it's done with cheap aftermarket junk. What are the cfms on the fans?
The stock fan setup never lets anyone down or has any adverse cooling or charging issues.
 

imp

Mustang Master
Jul 13, 2017
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#24
  • Jul 16, 2017
  • #24
Has the question been raised, did the engine run too hot BEFORE electric fans were installed? Generally, my opinion only, but based on personal experience, electric fans are no damned good. imp
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
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Jul 16, 2017
#25
  • Jul 16, 2017
  • #25
imp said:
Has the question been raised, did the engine run too hot BEFORE electric fans were installed? Generally, my opinion only, but based on personal experience, electric fans are no damned good. imp
Click to expand...
Then why do all the cars, trucks, buses, trains and airplanes use them now?
 
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imp

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Jul 13, 2017
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#26
  • Jul 16, 2017
  • #26
karthief said:
Then why do all the cars, trucks, buses, trains and airplanes use them now?
Click to expand...
@karthief
Do they? My Explorer has a fan clutch. Why do they use them? I dunno, but I can describe technical reasons, solid Engineering reasons, to explain my position as I stated it. Blindly accepting some particular trend makes little sense, wouldn't you agree? imp
 
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Dan Benavides

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Jul 17, 2017
#27
  • Jul 17, 2017
  • #27
Guys,
Here's the back ground in my overheating issue. As the weather got warmer so did the car with the stock radiator and fan clutch. This is why I decided to upgrade it.

I am using the stock instrument gauge to read the temp. It did work perfectly before the issues started. At the moment temps are reaching 250-260 degrees and do not change much when I am driving the car.

I don't know what brand the radiator or fans are. They are made in China.

Someone mentioned weather or not I see water flowing at the top of the radiator with the cap off, yes I do when the thermostat opens up but Its very slighty. When I rev the motor I can't really really tell if the flow increases, i don't think it does.

Any ideas? Could this still be the thermostat ? I'm very stumped at this point and becoming an expert at pulling the thermostat. The water passages looked clean when I replaced the water pump and timing cover so I don't think there's a clog in the system.

What should I do next ?
 

imp

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Jul 13, 2017
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Jul 17, 2017
#28
  • Jul 17, 2017
  • #28
Dan Benavides said:
Guys,
Here's the back ground in my overheating issue. As the weather got warmer so did the car with the stock radiator and fan clutch. This is why I decided to upgrade it.

I am using the stock instrument gauge to read the temp. It did work perfectly before the issues started. At the moment temps are reaching 250-260 degrees and do not change much when I am driving the car.

I don't know what brand the radiator or fans are. They are made in China.

Someone mentioned weather or not I see water flowing at the top of the radiator with the cap off, yes I do when the thermostat opens up but Its very slighty. When I rev the motor I can't really really tell if the flow increases, i don't think it does.

Any ideas? Could this still be the thermostat ? I'm very stumped at this point and becoming an expert at pulling the thermostat. The water passages looked clean when I replaced the water pump and timing cover so I don't think there's a clog in the system.

What should I do next ?
Click to expand...
@Dan Benavides
Look closely at the lower radiator hose. I have seen them collapsed enough occasionally to seriously restrict the flow. If opening the radiator cap cautiously allows looking in with a light, water flow should be readily visible, even at idle, of course, thermostat must be open (or left out, to do the flow test, best way). Good radiator hoses have a spiral wire spring within them to prevent collapsing, which usually is due to the suction produced by the water pump at it's inlet. imp
 

Real time recon

Mustang Master
Aug 21, 2016
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Jul 18, 2017
#29
  • Jul 18, 2017
  • #29
Looks like you have covered all the bases . But , perhaps there is STILL air in the system.It took me several tries / attempts to finally get it ALL out on my 302.
 
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Dan Benavides

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Jun 26, 2017
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Jul 18, 2017
#30
  • Jul 18, 2017
  • #30
imp said:
@Dan Benavides
Look closely at the lower radiator hose. I have seen them collapsed enough occasionally to seriously restrict the flow. If opening the radiator cap cautiously allows looking in with a light, water flow should be readily visible, even at idle, of course, thermostat must be open (or left out, to do the flow test, best way). Good radiator hoses have a spiral wire spring within them to prevent collapsing, which usually is due to the suction produced by the water pump at it's inlet. imp
Click to expand...

I checked the lower hose yesterday evening and it was not collapsed. There's plenty of pressure at the lower hose and there's visible water flow. I'm beginning to think the radiator and/or fans may not be sufficient.
 

MFE92

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Jul 20, 2017
#31
  • Jul 20, 2017
  • #31
I'm starting to think cracked head or head gasket. Run a compression test on every cylinder.
 
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Dan Benavides

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Jul 21, 2017
#32
  • Jul 21, 2017
  • #32
MFE92 said:
I'm starting to think cracked head or head gasket. Run a compression test on every cylinder.
Click to expand...
Yeah I took the car to a local mustang shop and they told me that they ran a radiator test and the fluid turned pink. They seam to think that the block may be cracked. They are going to open up the motor and check everything out. I hope it's just the head gaskets but if it's the block I'm going to have to find a new block. At that point I don't know if I should keep the 302 or just swap in a 351? I'm not trying to spend too much money.
 
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General karthief

wonder how much it would cost to ship you a pair
5 Year Member
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Jul 21, 2017
#33
  • Jul 21, 2017
  • #33
Dan Benavides said:
Yeah I took the car to a local mustang shop and they told me that they ran a radiator test and the fluid turned pink. They seam to think that the block may be cracked. They are going to open up the motor and check everything out. I hope it's just the head gaskets but if it's the block I'm going to have to find a new block. At that point I don't know if I should keep the 302 or just swap in a 351? I'm not trying to spend too much money.
Click to expand...
Grab another 5.0, I wouldn't consider a 351 a 'budget swap' although it could be with some sharp searching, and not all 5.0's are the same, some have lower compression than others.
 

2000xp8

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Jul 21, 2017
#34
  • Jul 21, 2017
  • #34
I really doubt it's a crack, I don't think a stock 302 block would stay together cracked.
 
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Dan Benavides

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Jun 26, 2017
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Jul 23, 2017
#35
  • Jul 23, 2017
  • #35
I stopped my the shop yesterday and the mechanic had the heads off the car. He told me that he found water in the two rear cyclinders but that the head gasket was good. He's still leaning towards the block being cracked. He said he will have the block out by Tuesday.

He also showed me that the valves where hitting the pistons. So the previous owner that rebuilt the engine didn't do a good job with the valve clearance.

This sounds like it's going to be an expensive repair. I'll keep you guys posted.
 

mikestang63

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Jul 23, 2017
#36
  • Jul 23, 2017
  • #36
explorer motor time
 
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Martman

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Jul 26, 2017
#37
  • Jul 26, 2017
  • #37
Just getting to this thread and see you are beyond my recommendation but thought I would put this idea out there as the title will probably draw others in for overheating research. If the car is/was equipped with A/C and has the condenser still in place you need to check and make sure it is flowing enough air. If it is too damaged it sits in front of the radiator and can restrict airflow significantly. In the winter the ambient air temp can allow a good radiator to overcome minimum airflow. But as temps in the summer rise, that air flow is very very important.

Good luck on your repairs. And don't be like me and normally try to save a dollar as it never works.
 
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